Mr. Obama Goes to Copenhagen

The Huffington Post uses the photo at left to illustrate the President's speech at the Copenhagen Conference on Climate Change. The President's tone is severe, disappointed, almost grim. Hit the link to see the text of his remarks. His disappointment centers around the many wrenches being thrown into the process of dealing with climate change by both undeveloped and developing countries.
China, the world's most egregious polluter by a comfortable margin (with the USA running a clean second), is balking at the proposed cap-and-trade and sin tax measures that would both penalize major polluters, like China, and provide carbon credits for more slowly developing countries (read most of Africa) to use or possibly to sell to polluting nations to earn badly needed cash for their own programs. Even the African nations, and others in similar circumstances, are demanding the right to "grow dirty" for as long as they want, citing the poor record of the US, China and other industrial nations over the last two centuries as polluters.
Unwilling to accept a progressive cap-and-trade system like the one under consideration, the poorest nations at the conference are demanding either huge monetary concessions in return for their cooperation with carbon emissions limitations, or an exemption that will allow them to pursue economic growth at an advantage while the larger countries accept limited carbon emissions standards.
With these mulish denials ringing in his ears, Obama warned us that we can either act now, and decisively, or return to the table to have "these same stale conversations." That must have stung the Chinese and Africans.....
So what can you do at home to persuade the Africans and Chinese to think globally and accept the limitations of "low carbon growth?" Not much directly, sad to say. But if Americans were to show a national will to conserve, take charge of our own carbon footprints (this link is to an earlier post on that topic), and show a preference for lower-impact houses and cars, the message would not be wasted on a world which has looked to us for almost two centuries as trendsetters and innovators. It looks bad for us to be stuck in our denial of climate change and the inevitable scarcity of energy. Enlightened, attentive leadership is what we demanded when we elected Barack Obama. Enlightened leadership is what the world expects of us, and they have shown their willingness to follow suit. They want our blue jeans, they want our sneakers, they want our cell phones, and they'll want our energy policies when we have some worth sharing.

Update at Our House-- Solar Hot Water

This brief post will keep us close to home. I noted our new solar hot water system a few weeks ago, stressing our modest expectations for winter performance. I have to say I'm pleasantly surprised.
Today, December 6, the temperature in our town topped out in the 30s, we got three inches (up on this high hill, we get more) of wet, icy snow last night, and the winds were gusting to 15 miles or so as the day wore on. I checked the panel temp this morning after hearing the snow and ice avalanche off the collectors at 9 AM or so. 100 degrees on the return fluid thermometer.
Cutting to the jelly, I just ran hot water at 105 from my kitchen tap. One day of performance, 80 gallons of shower-ready water. Two 4x7 Stiebel Eltron flat plate panels (evacuated tubes are nice, but not necessary) two 40 gallon stainless holding tanks with heat exchanger coils for the solar fluid. One Caleffi (pricey, but very flexible) solar differential pump control. Very short connecting pipe (under ten feet total) between the panels and the tanks, located on my roof and in my attic, respectively.
As we near the solstice, and as temperatures drop into the teens and oughts, performance will certainly drop. But it won't drop to zero. We'll get pre-warmed water for the boiler to finish off on every sunny day from now until March equinox. I hope, after that, we'll be getting near total solar hot water for some months.
So--- a few thousand dollars (I, a seasoned solar contractor, did the installation myself) in equipment, a prime roof spot oriented within 15 degrees of south, a relatively un-obstructed morning horizon (the afternoon sun is hampered by some tall trees), a solar day extending from 9 AM to about 3 PM, and this is what we're getting for an energy harvest. DEP figures concerning hot water as a proportion of total household energy are being revised upward, to a possible 25%. If that's so, and I believe it in our case, I'll look for a 25% drop in our fuel oil usage this winter. And, at nearly 60, I expect to bequeath this system to a future owner someday, still running, still harvesting that blessed free energy from God's own fusion bomb, the sun.

Today's Science Project, Tomorrow's Energy Source

There are three listings in the Southeastern Connecticut Yellow Pages under "Solar Contractors." There are 876 approved applications to date for rebates under the Connecticut Clean Energy Fund program, for a total connected capacity of 4 megawatts. That will power 8000 small houses during peak daylight hours, if it all gets used efficiently. For a few hours on the sunniest days. There is one photovoltaic installation within easy driving distance of my home in North Stonington. The Connecticut Clean Energy Rebate program is shut down until July of 2010 for "financial review."
Solar is not setting the world on fire here in Connecticut, is the point. The approved leasing program that allows homeowners to join the energy revolution does not convey the tax credits and rebates available to those buying their equipment. You just get to sell the power back to the grid, defraying your power bill by a fraction, depending upon your usage. Oil is cheap, to those who have any money at all, and the outcry for alternative energy sources is down to a murmur, mostly heard from the same folks who have been calling for change since Jimmy Carter funded the first rebate program for solar in the 70s.
If solar power, both for hot water and electricity, is to catch on in the mind of the public, we need a consciousness-raising experience, preferably several.
So how about small solar that you can give Dad as a Christmas gift, a kit of panels, inverter and batteries that he can assemble in the garage or basement, set out in the back yard, and start calculating the incoming watts from the sun? You can't hook these small kits up to the grid, for many reasons, but you can run a light or two, power a tool, charge the battery on the car, operate landscape lighting, or operate a decorative fountain pump. Use your creative side here.
These links to various vendors who package and ship the equipment, with many disclaimers, right to your door. Target has kits on the shelf. One of the vendors linked above will sell you a kit to power the whole house, even go on the grid if all your permits are lined up. The amounts of power are tiny, ranging from 10 to 75 watts per hour, but the principle is real, and the operation is only a scaled-down version of huge systems sitting on commercial and residential roofs where public conscioiusness has been raised already.
Perhaps we ony need to toy with these concepts for a few years before we're ready to accept the value of photovoltaics as significant contributors to Connecticut's energy picture. Perhaps a science project or two will get us into the game, or at least thinking in the right direction. Read the instructions, be very careful, and let me know how it turns out.....

Entry Level Solar Hot Water- Real People Can Do This Right Now

I blew this diagram up so you can make out the details; it's from a Williams College site describing a system they put in a graduate dorm. The essentials are this: the panels receive cool water from tank dedicated to solar, warm it up in the passage through the panel, return it to a heat exchanger in the solar tank that warms the domestic water. When hot water is demanded, the solar "pre-heated" water passes into a tank warmed by a boiler which increases its temperature to a setpoint for use in the building.
It's called pre-heating, and that's the little point I want to make in this post. When you aim a low-temperature all-weather solar setup at a low temperature need, it performs beautifully. Asking a solar hot water system to finish your water off to 125 F or more is asking too much. Only during sunny summer weather will the system carry that burden.
In one pass through two panels on a sunny winter's day, you might raise the fluid temperature by only three degrees F. You might run that system all day until sundown and have warmed an 80 gallon tank only to 85 degrees (from 45 to 50 degrees incoming temp, depending upon whether you have city supply or well water). But 40 degrees rise for 80 gallons comes to almost 13 thousand btu that you didn't have to pay for. And it means your finishing, or backup source will run that much less to get the water hot enough to use. On a sunny day you might raise the same tank of water all the way to terminal temperature (app. 130 degrees). That's 26,000 btu from the sun. You might want to run your finishing source a little, but it only has to raise the temp a few degrees. Energy is being saved on a grander scale by allowing the solar panels to operate at a lower temperature, where the sun and the heat exchanger are able to deliver energy more efficiently.
I have clients with solar systems sharing a tank with electric finishing elements. They only get solar benefit when the panels are as hot as the terminal temperature setting of the domestic water. There just aren't that many days in CT when the panels get hot enough to finish off the water in one pass.
And the cost? Fewer panels and smaller tanks do more work at lower temps. A tank only has to be a about as large as your daily water demand to deliver its full potential as a preheater. It needs to be much larger to store heated water against cloudy days and night time losses. So while you're waiting for the cost of photovoltaics to come down, and wondering what you can do to join the green movement, solar hot water in a pre-heating configuration is the most cost effective entry level investment. Most systems can be installed for less than ten thousand dollars US, and they attach to your hot water piping just ahead of whatever your water has been heated by in the past: electric tank, boiler coil, external heat exchanger or woodstove. With photovoltaic systems starting at about 30,000 d0llars, and paying back rather slowly, this solar hot water option is appealing at several levels. You can get free energy from the sun, with not much red tape, and get the federal and state tax credits that reduce the cost of the system by as much as 50% depending upon your location and the system cost. That's a game we normal people can think about jumping into, and nothing feels as good as a nearly free shower.

Compact Fluorescents-- Serve Me a Dish of Crow

Guess how many of the bulbs in the photo are energy-efficient compact fluorescents? Yes, of course it's a trick... ok, all of them, smartypants. And that's the point of this post: to retract my longstanding opposition to compact fluorescent bulbs, and to get you to take a fresh look at a new generation of energy-efficient lighting that saves money while still doing the job well.
About fifteen years ago compact fluorescent lights appeared on my contractor's radar; clients were asking about them, the public utility was hawking them in discount programs, and I was the stodgy old guy telling everyone to wait, the product wasn't really up to the challenge, and removing the fixtures people insisted on buying in a rosy glow of greenness. The dim, harsh, flickering, watery, slow-to-light fluorescents that were supposed to change the world and lower our power bills have been a terrible disappointment, as this George Will essay sarcastically details.
And I, monsieur energy contractor, installing the latest in efficient heating and cooling equipment, and the best in automated home lighting systems that turn off when not needed to save money, was the naysayer who steered everyone away from the latest trends in alternative lighting.
Until now. it's time to retract, and I'm doing it publicly. This link is to a catalog site showing many styles and brilliances of fluorescent and LED lighting, and while there are still caveats restraining the homeowner from believing every claim that GE and Phillips make for their new bulbs, I'm changing my stance and coming out for compact fluorescent retrofit bulbs, the ones that can be screwed into an old-style socket to replace an incandescent bulb.
The quality of the light is still "variable." If you choose the "daylight" or "soft white" color options at the home store, you'll probably be satisfied with the color and warmth of the light, even if it's a bit whiter than your old incandescent bulbs.
The intensity is appropriate to the fixture. Compact fluorescents are now prominently labeled for their "lumen" output, a more telling measure than the old "watts" per bulb number. Buy a bulb equal to the lumen output of your old bulb, whatever the wattage, and you'll get enough light. Notice, while you're doing that, that your new fluorescent retrofit bulb costs as much as ten times what you've been paying for incandescent light bulbs, and is rated to last as much as twenty times as long; and this time they're probably telling the truth. Older fluorescent retrofits were shorter-lived and grew dimmer as they aged.
Are all compact fluorescent bulbs created equal? No, sorry. Beware of those not costing significantly more than incandescents, and stick to brands like Phillips and GE rather than those packages which clearly indicate their foreign manufacture and sport suspiciously lower prices. The technology you're paying for is not cheap, and you'll be disappointed with the cheapest fluorescent retrofits. Check this Popular Mechanics link to a shootout test. Be told, as Granny used to say.
Environmental concerns? They're real. Compact fluorescents contain a small dose of mercury, which poses no threat unless the bulb is broken. Incandescents are also not safe when broken, so all the same warnings apply. When the dog knocks over the lamp, shoo the kids out of the room and use the vacuum; carefully. Here's an Energy Star data sheet to help you.
And how do the numbers work out? They work. A compact fluorescent using twelve watts of power competes with an incandescent 60 watt bulb for performance, lasts many times as long, and costs five or six dollars rather than 5o cents. That's twenty five percent of the power, with a service life that works out as a bargain even ignoring the energy savings.
We've blogged before about LED bulbs, and expressed our reservations. We still harbor those reservations. Maybe we'll visit that topic soon.. Until then, you can go to the big box store, or a good supermarket, and buy the compact fluorescents with confidence. Use them in lights you leave on a lot, not your basement or your closets. Then they'll do you some real good. And I'm replacing the incandescents at my house, too. We walk what we talk......

Connecticut Energy Lip Service

If the electric meter in the photo were spinning backward, it would mean that the home it serves is using photovoltaic panels to push power back into the grid. In Connecticut, not the least progressive state in the union concerning renewable energy, the power is resold to the utility at retail, or exactly the cost homeowners are paying for their power. A corollary of the "Net Metering" system is that Connecticut Light and Power makes nothing on those watts contributed by photovoltaic-equipped homeowners: retail in, retail out. If there were enough of those homes hooked to the grid, the utility would become essentially a grid-maintenance corporation and the turbines at Millstone Nucular Power Plant would be idle-- except maybe at night, when demand is low and the solar panels of Connecticut are running on moonlight. Small danger of that scenario, you say? You're probably right. But like Dylan's 115th Dream, it's a nice one to have now and then.
If that meter were located in California, things would be a little different. The power flowing out through it from the residential photovoltaic array would be metered at an increased rate, higher than that charged for incoming power. The owner of the panels would be making a profit over and above the exchange of watts. And the obvious incentive to upsize the system and supply extra watts to the grid at that "Tariff-enhanced" rate is clear to anyone. Photovoltaic installation companies in California will now find it easier to "upsell" larger systems to homeowners, systems that will cost tens of thousands of dollars more than the basic entry level equipment, and those homeowners who commit those extra sums of money to renewable energy will be rewarded by faster payback on their investments, and real profits after their installation costs have been recouped.
This US Dept of Energy link explains the new tariff, applicable both to residential and commercial renewable installations up to 1.5 megawatts (a typical residential installation in CT is about 3 thousand watts) at differing tariff rates, making it attractive to invest sums starting around $40k and rising to staggering sums (for me, anyway) for home solar installations. Solar "thermal", or hot water and heating, installations are already rewarded by California's wonderful sunny climate, enabling folks like us to enjoy nearly free hot water and heating year-round.
The Bad News? Here in Connecticut we do have net metering, as we said. But the Connecticut Clean Energy Fund, which administers and disburses the energy rebates that subsidize solar installations in the state, is currently "under financial review," meaning "not disbursing new rebates." I am advised by a CCEF representative that the next disbursements are projected for July of 2010, and that rebates for commercial solar installations have been temporarily suspended. Why? The funds are developed from surcharges and contributions on consumers' power bills, and CL&P has been short of funds lately since Attorney General Richard Blumenthal denied their request for a rate hike. So it appears that CL&P is economizing their way through this tough period by shorting, among other things, the Clean Energy Rebate program. With the rebates working, a photovoltaic system still costs quite a bit ($30,000 and up), but with no rebates the cost of the systems almost doubles.
Decreasing equipment costs are helping contractors to bring the price of system installations down in the last year, but those gains still don't put renewable energy within the reach of folks with modest incomes and modest borrowable equity in their homes. And the tally of renewable solar systems installed under the rebate program since june of 2009 totals just under 4 megawatts. Four megawatts is enough to power my house for about a year.
So--- we progress, but slowly. And we progress with much talk and belated action. Nothing wrong with talk, but it's disappointing when we see the tiny advances we make over time. All in all, we lack what is called the "political will," or the consent of the people, in other words, to move ahead on these issues.

Teaching America to Fish

On rare occasions we get a little global and a bit political in this home-focused energy blog. The photo at left shows, in minuscule scale at bottom, a house in Mongolia adorned with various solar devices: photovoltaics, solar hot water, passive window orientation, like that. It is part of a new thrust in Chinese policy which swerves sharply away from the "let them eat soot" approach previously taken in China's dizzying progress through the swiftest and most aggressive industrial and technological revolution the planet has yet seen. In one respect only does China fail to eclipse the industrial revolutions of, say, Britain and the US: creative innovation, and that missing ingredient has been willingly supplied by a West eager to trade its technological treasure for the privilege of having our toasters made for us cheaply and in astonishing quantity.
China has become a smokestack economy over the last 40 years, replacing farms with factories while maintaining an adequate agricultural sector and keeping everyone fed. The air, water and land in China have suffered, along with the health of the Chinese people, in predictable ways as the industrial economy has grown by leaps and bounds. Chinese air and water quality have become a global joke, something to point to when defending some environmental foolishness on the part of a nation which should know better. But,,,, but,,,, we're not as bad as the Chinese, they sputter. And one significant argument against an aggressive response to global climate change has been, why do our part, when the Chinese are the biggest polluters and they have no intention of changing?
As it turns out, China, with its now-customary swiftness, is directing its attention to energy policy and global climate change. This link is to a United Nations site which records that China will meet a goal of 20% reduction in energy intensity by the end of 2010. Are the Chinese, not to put too fine a point on it, just blowing smoke at us? It wouldn't be the first time. But independent observers confirm that at least part of this claim is true: that China is moving toward a national energy awareness, if not independence. China is the single largest consumer of energy on the planet, and the largest importer of oil. It has its own reserves of coal and some natural gas, which it supplements with purchased gas from Russia. Small surprise: China exports coal to America, and it imports coal for special industrial use (steel production). And 70% of China's power is generated by coal-burning plants.
To come to the point: China is now the single largest manufacturer of solar panels. The largest solar farms and panel arrays in the world are planned for Chinese locations over the next few years. The solar power production of Europe and Scandinavia, which put the U.S. to shame, are being dwarfed by Chinese installations now in operation. We will soon be unable to point to China as the dragging foot in the war on global climate change and the struggle for renewable energy dominance. By the next Presidential election the U.S. will be embarrassingly behind most of the developed nations in energy independence and renewables production.
Thomas Friedman, New York Times columnist, writes in a recent column that "China has the most aggressive renewable energy deployment in the world." He writes elsewhere that American reluctance to consider measures like a hefty gas tax, research on clean nuclear energy, and significant subsidies for renewable energy production have already caused us to lag behind Europe and Scandinavia. Soon, he says, we will be lagging behind Asia, and after that? Will Latin America also eclipse us as we move into the "Energy Century?" What will it take?
Leadership in this most miraculous of nations (that's us, by the way--- America the beautiful, in which I have implicit faith) comes from both the top and the bottom rungs of the power ladder. We respond to grassroots leadership (that was the 60s, you unbelievers, the last great grassroots movement in America) as well as to great political leadership (that would be the Clintons, pointing the way to broad-based national health care), and even when that leadership leaves the stage, the ideas remain to sprout and grow. We are now reaping a harvest of change from Hillary's sacrificial efforts in the 90s, and we stop at Whole Foods on the way home thanks to a little fad begun in the 60s by some fanatics who had read too much Rachel Carson. We will be dragged into sanity in the near future by leaders like Al Gore and others who are now being shouted down by an oil-subsidized opposition, and America will become an energy leader again. I await the day. Meantime, I'll keep blogging, installing tight windows, nailing solar panels onto my house, and trying to reduce my energy footprint. Next time we'll get back on task with home topics.

Solar Panels No Problem in Cloudy Weather

I happened to be cleaning a boiler this morning at the home of one of my solar clients, and i checked the system over. 50 degrees out, cloudy enough so that I couldn't tellwhere the sun was in the sky. The two Heliodyne panels were reading 95 degrees, the pump was cranking away, and the two 60 gallon storage tanks were being warmed. All in weather not normally seen as optimal for solar hot water systems. The oil fired boiler in this system only has to raise the water temperature to 130 degrees to serve the dishwasher, laundry and showers. Lots of energy was being saved by the solar equipment in that house.
I didn't build the panels, or the heat exchanger, but I did design and install the system. It performs beyond expectations. The new optically selective coatings being used on flat plate panels will collect photons and transform them into heat much more efficiently than flat black paint or a bare surface.
This is a short post, an update on some things we've discussed lately. Don't believe the dismissive comments about solar hot water being a three or four month blessing. Solar hot water, thoughtfully installed, will perform for you on sunny days twelve months a year in New England. Connected as a pre-heating treatment with an energy source configured to finish the water off to usable temperatures, solar panels can be working for you all winter long, even on cloudy days.

Phil's 113th Energy Dream

The diagram at left teaches you more than most folks want to know about boiler internals, specifically horizontal three-pass cast iron. There are many clever variations on the theme of torturing hot fumes before releasing them to the chimney and the heavens, and this one has been used for two generations in big commercial boilers powering factories and hospitals. Only lately do we rise above the heavy, hollow cast units many of you still have in the basement.

Don't think me smug, I service boilers performing at 75% efficiency all over the county, and the Biasi in my attic gets around 87%. There's not a huge harvest of energy to be reaped yet from changing boiler designs until we find a way to deal with the acids and sludge condensed in boilers at lower temperatures. In Europe they've refined the sulfur almost entirely out of their fuel, yielding something almost as clear as kerosene. The link is to a British site listing oil boilers boasting 97& efficiency. Shame on us Yanks. I won't delve into the technology of boilers with condensing exhaust, but just imagine something vented through a light metal tube at less than 200 degrees, with sulfuric acid and dissolved ash dripping from a draincock on the flue.

My Biasi is among the high society of boilers,sold in the US, but it hails from Italy. Its nearest competitors are made in Germany, Germany and Italy, respectively. There are American multipass designs being sold, but they lag behind in the critical qualities of low mass, low volume and low stack temperatures. Makes you think, don't it? At app. 2.10 US dollars per gallon on Labor Day weekend, heating oil is as cheap as it's been in years, and we Americans see no reason to respond, apparently to anything but brute market forces. Price, in other words.

The little B4 model weighs in at 300 lb. dry weight. We hauled it up through the scuttle hatch with a light comealong rigged to a single unbraced rafter. Piece of cake. Why am I in such a lather to get it up there? It doesn't require a conventional chimney (my house doesn't have a conventional chimney), and the vent is through a single length of capped stainless steel chimney pipe extending through the roof on the leeward side of the house. It's also within 6 feet of the blower unit that heats my house. The water heated by the boiler travels no distance at all, losing almost no heat to the surrounding air. It sits in a metal pan piped to a nearby sewer vent pipe.
For domestic hot water, imagine a stainless steel block heat exchanger the size of a shoebox hanging off the back of the boiler. When someone hits a switch either in the kitchen or bath, the control starts the boiler water circulating through the exchanger, heating domestic water in one pass hot enough to do dishes, shower or operate the laundry. But you have to hit the switch, otherwise the little Biasi sits there cold. Time to hot water, from a standing start? Three minutes by the stopwatch. I know, America can't wait for its hot water, and can't be bothered to hit a switch. But this is how it goes at my house. You get up to an hour of glorious hot water from a twist of the timer. Otherwise you wash your hands in cool or tepid water warmed a little by its passage through the house pipes.

Antifreeze protects the boiler, blower coil and heat exchanger from freeze damage, and the attic is insulated against bitter outdoor temperatures. I have to use a little pump, fashioned from an old oil burner, to lift fuel to the attic for the boiler. That adapted unit sits in the basement next to the oil tanks, pushing a dribble of oil up to a heavy steel reservoir which feeds the burner by gravity. My house, insulated through various remodeling projects over thirty years to respectable R values and tightness, will be comfortable this winter without any renewable energy resources other than some carefully planned passive solar (click to see an older post on our sunroom).

Will I put a system like this one in your house? Not until we talk. Talk a lot. Show me your old copies of the Whole Earth Catalog, or the original pulp-format Mother Earth News. Tell me you were at Woodstock, and why I didn't see you there (I missed Woodstock, that's why). Show me your green-friendly stock portfolio, your Energy Star appliances, your first pair of Birkenstocks. And assure me you're willing to wait three minutes for hot water at any tap in the house, think before you hit the switch whether you really want to spend that energy, and let Dirty Phil into your house at least once a year for a boiler cleaning and efficiency check. And then, maybe. How can I be sure you're ready to take this step? Soon I'll be blogging about the solar hot water system that will be incorporated into my attic this fall. Stay tuned.

More Hot Water Options, and My Favorite

The photo is borrowed from a charming blog post dealing with gender differences in showering styles. But we're here to wrap up, for now, the subject of domestic hot water options for energy conscious homeowners.
We've talked about tankless water heaters, solar water heaters, electric tanks and furnace coils. Here are a few more to round out the picture for you.
If you have a coil in your oil or gas fired boiler, you might consider upgrading to an indirect hot water tank. There are two styles, one in which boiler water fills the tank, and one in which boiler water fills only a coil in the tank. My favorite is the former, for efficiency. This link is for an excellent design by Dunkirk. The boiler is relieved of its duty to stay hot as heck all the time, running only when a tank thermostat calls for it to warm up the tank, or when hot water is being used. You save considerable on "standby losses" and seldom experience a delay of hot water due to the tank's capacity. The insulation of the tank makes it a better reservoir for heat, and you can over-wrap it yourself and do even better.
There is also the option of putting the oil burner right under the tank and heating it up directly. A "direct fired hot water heater" is a tank sitting over a firebox with a burner and a flue. Standby losses are a bit greater with the direct design, but the recovery rate of the tank temperature is amazing, and it's hard to run out of hot water even with teenagers in the house.
I recommend you use the link and look at what Energy Kinetics has done with the concept of hot water production and standby losses. Their systems are pricey and require considerable expertise to install correctly, but the savings give you an accelerated payback over the classic cast iron boiler with internal hot water coil. A smart controller starts the low mass (low mass, low volume, quick heatup, small amount of energy trapped in boiler upon shutdown) stainless boiler up cold, turns on a circulator to respond to heating needs, and circulates boiler water through a flat plate heat exchanger piped outside of the boiler. domestic hot water is heated in one pass, or a separate circulator warms a well insulated storage tank to provide water that doesn't fluctuate much in temperature (this temperature fluctuation is the most common complaint from boiler coil people, other than high energy costs). At the end of a heating/hot water cycle, the boiler circulator stays on until the heat has been "dumped" into a waiting zone or the hot water tank. Not much gets wasted. I seldom directly plug a company in this blog, but no one else is doing exactly what Energy Kinetics is doing, and I think they're ahead of their time in a notoriously sluggish industry in a notoriously energy-spoiled culture. Good for them.
Next post I'll talk about the system I just installed in my own house, a real pound puppy of assembled energy efficient components crafted to my own design. Stay with us...... meanwhile, if you'd like to discuss your own options for upgrading your hot water system, hit the contact link and i'll be happy to respond.

Sunbathing Once Removed - Solar Hot Water and You

The device at left is a self-contained solar hot water heater, featuring panels, mounting frame, and tank at the top. it requires no power for pumps or controls. Water from the tank circulates through the collector plates by convection as the sun heats it, filling the tank with water at whatever temperature the sun can warm it. The tank remains at house pressure, waiting for a demand. At night the tank cools slowly, delivering hot water until the tank is cooled completely.
You can't take a shower at midnight with this rig, unless no one else has used water that evening. You can't store more water than can be held in the tank. You can't rely upon the supply first thing in the morning, or later in the morning, unless the outside temp is so high that the tank doesn't cool much. You can't install this system in a climate where winter temps drop to freezing or below; or, you can't use the system more than five months a year in New England where I live, and it must be drained for the winter when hot water is supplied by another system. You can't supply the hot water needs of an American family of four unless they're all atuned to the daily cycles of water heating and time their use of hot water in zen-like harmonious balance with the (i'm singing now, in a sloppy baritone) "Cirrrrrcle of Liiiiiiffffe." No audio available on that one....
You get the picture? The system shown is not acceptable for Americans. No system I know of is acceptable to Americans, with the exception of aging hippies with dearly held beliefs on the subject. I installed a system several years ago for clients with those dearly held beliefs about energy and independence, but the system nevertheless had to be carefully integrated with a seamless backup, sized to provide hot water for every possible demand including house guests, and separated from the house water supply by a closed-loop heat exchanger filled with antifreeze to prevent freezing. Sporting those features, it cost a small bundle, which federal and state incentives defrayed by over half (here in CT, at the time, state rebates were generous; since then, with a huge budget deficit, those rebates have withered). But it supplies "tempered" (pre-heated) water to their oil-fired backup system on any sunny day in any month of the year, and supplies all of their hot water needs for about six months out of twelve.
That's what Americans require: seamless integration of alternative energy systems into an American lifestyle which forfeits no convenience to the idea of sustainable energy technology. I could sell a lot of the systems shown in the picture; they would supply the hot water needs of a couple for at least the three warmest months of the NewEngland year, saving 25% of the energy costs in a category (domestic hot water) that accounts for at least 30% of an American family's energy bill. Yes; that's 8% of the household's energy costs, defrayed by a system that must be lived with a state of awareness and harmony. No, I won't sing again. The payback period of the system would be about eight years, and it has a life cycle of perhaps 30 years. But all the caveats listed above still apply. You have to live with what the system can do, and what it can't do. How many of my clients are willing to make those lifestyle adjustments? Hands up? I don't see any hands. Guess what? My hand's not up, and I'm an energy-conscious aging hippie and heating/cooling contractor committed to renewables. I'm an American, and I want my hot water without compromise.
There are other solar hot water systems, other designs that contribute to a home's hot water needs in a more American way. This USDE site gives an overview. Costs range from 8 to 25 thousand dollars US to install, and they pay back your investment over periods ranging from ten to 25 years. Do you know how fast they're selling in Connecticut? Not fast at all, especially as the rebates recede and the federal tax incentives age toward 2015, when they will either be renewed or not.
I always plump for low technology, low cost, modest gain energy strategies in this blog and in my business, but I haven't found a way to put solar hot water within the reach of average homeowners yet. The renewables train is coming slowly around the bend, and there's a lot of hemming and hawing among homeowners who'd rather replace windows and siding than invest in solar technology, because that's what's being hawked on the telly. I'm a very modest salesman, with a conscience I wear upon my sleeve, and I can't promise more than the numbers tell me when I talk up renewables. The number are still tough, but they work in the long haul. We need a national, cultural sea change, a tipping point. If it's not on the infomercials, it's not hot. Al Gore can't sell this one: I can't sell this one. The renewables movement is waiting for someone to sell it to America; perhaps only Tom Hanks is up to the job.

It's a Tankless Job

If I could give up the cruddy puns, I'd have more readers. As it is, the two of you are most welcome, and I salute your tolerant natures. The contraption shown at left is called a "tankless water heater." This one is fired by propane, although we could show you electric or oil-fired models, and even a few that use wood. The idea is simple, but simple ideas are always hell for engineers. Water enters cold, leaves hot enough for American bath and kitchen use, and not much energy goes up the flue, if you believe the labels.
Compared to the electric tank that sits in my basement, the tankless heater is a marvel of efficiency. A crafty heat exchanger exposes the water to the gas flames/electric elements such that heat transfers at efficiency ratios up to 95%. My electric tank operates at closer to 85% due to various factors, mostly standby (idle) heat loss from the tank.
The tankless heater sits cold, or barely warm, until you turn on the shower/faucet/dishwasher/laundry/jacuzzi. A flow switch alerts the unit that water is demanded, and the btus begin to flow immediately. A delay attends the operation of the heater, during which you run water, wasting a bit, and wait for the hot stuff. Usually fifteen to thirty seconds is enough. Then, as long as you continue to demand hot water continuously, the heater can produce as much as you can use, within limits.
Properly sized, the tankless heater will serve one point of use or several in your house. You calculate the capacity by the number of occupants and their habits. Teenagers count as a small village each. Old men like me are no big problem. Can I run the dishwasher while showering? Shall I operate the clothes washer and the dishwasher at the same time? There are easy formulas to help you get this right in one go.
The capacity for heating water in one pass is a thing that separates the tigers from the kittens. Electric tankless units are generally of smaller capacity, and two or more are installed in series to raise water to the desired temperature as it traverses the multiple heat exchangers. Propane or natural gas heaters are more aggressive, and usually one correctly sized heater will serve an average house. Only Republicans, to date, have been willing to accept the risks of the nuclear option, but they say the water is always hot. And wood burners can easily adjust the intensity of their heating plants by adding more logs/pellets/kindling to keep the heat exchanger cooking. The Waltons' method, of course, was technically tankless, involving multiple pots hung over the fireplace and carried to the big washtub where a dirty Walton waited to be scalded clean.
We spent the last week at a "resort" (weathered 80 year old shacks perched on the dunes) on Cape Cod. The single modern convenience, besides a rather sluggish flush toilet (more on that topic only by request) is copious hot water supplied by propane-fired tankless heaters. Crank the shower control, wait a good half-minute, temper a bit with cold, and step in for the best shower you can get at any price. Yes, the shower's indoors; and it's also outdoors--- your choice. The blunt simplicity of the amenities is only meant to enhance your appreciation of the stunning views of sea, sand, birds, seals, whales (!), and well-fed tourists only capturable through wide-angle lenses. No, I won't tell you where it is: they don't advertise, and the waiting list stretches years in front of hopeful vacationers. Elitism has many faces.
At your house, the water heater can cost from $1 US to $3 US, depending upon the energy source and the equipment. If you've got a solar hot water system, you might be getting off VERY cheaply during these sunny warm days of summer. Pennies per day, just enough to run your pumps and sensors. Good for you. Next time we'll revisit hot water and talk a bit about the more conventional optons.

One More Reason to Hate Skinny People- They Stay Cooler

There are no Models any more; only "supermodels" and "weight loss contestants." The woman in the silhouette photo at left may be an expensive sweetheart in many ways, but the physics says she's at least easier to keep cool.
It's almost a "duh" moment to reveal that skinny people stay cool at higher temperatures, I suppose. But since I stopped being skinny, I've been indulging in denial about my need for greater cooling comfort. At two hundred pounds of aging manhood, I suffer a bit more in the heat and humidity than I did a few years ago. And you?
A Hawaiian blogger from Hilo cites a study exploring the relationship between body mass and the need for more cooling. Apparently larger, heavier people expend fewer calories through normal indoor activity, but they require lower AC temps even so. Ok, I get that. And there's a twist. The study poses the question whether the popularity of largeness has itself causes our increasing dependence upon mechanical cooling, or whether THE AIR CONDITIONING ITSELF HAS CAUSED US TO GET FATTER!
As Dave Barry often says, I am sooooooo not making this up. If reducing our heat stress in summer causes us to eat more, ok, maybe. If reducing our heat stress simply permits larger people to survive summer, ok, maybe. Or if heat stress is a weight loss technique we should all be considering, well, I don't like it, but maybe.
In the case of my embarrassing spread, I don't think my air conditioner is the real perp. I think I did it to myself. But a guilty air conditioner may cost less to run. I can be stingier with the thermostat. I can do yoga in front of the TV. I can eat salad with almost no dresssing while i do yoga in front of the TV, occasionally glaring at the thermostat. I can work in the heat all day and come home to a cool house, drink ice water and bask in the relief from heat stress. I don't think I should swelter until I reach my ideal weight. I think I may live longer if I don't have to court heat exhaustion, dehydration, depression, grouchiness, malaise and unpleasant body odors when it gets hot outside.
I want my AC. Forget the study linking obesity with air conditioning. I can adjust. I'll drink so much water I won't even be hungry. And if the supermodel gets chilly, she can go outside and pose........

Smell That Fresh Air! Where Do YOU LIve?

I put good filters into the HVAC equipment I install. Sometimes, on request, I install special electronic or ultraviolet purifiers that remove living thingies from the air inside your house. But that's only inside. We can battle the pet dander, dust mites, pollen and even germs floating in your indoor air. But we can't fight what 's going on outside.
The air quality where you live depends upon many things: surrounding plant life, animals living nearby, cities and manufacturing plants upwind of you, and nuclear testing in China, believe it or not. If you live just outside, say, Gary, Indiana, or on the east side of the Bronx, or in LA during smog season, you have to live with what man does to the environment in the course of American living: automobile exhaust, industrial emissions and the smoke from too many chimneys affect us when we breathe.
But I live in the country! Miles and miles of luxurious forest, hayfields, amber waves of grain, native casinos (non-emitters, they swear, very harmonious wit' nature), placid cattle grazing in fields fenced by rubble-stone walls. I love New England. But the air quality where I live is not free of challenge. Ragweed, milkweed, conifer pollen, asters, wild grasses, oak and the cows' behinds all emit stuff that I'm allergic to. On sultry August days I have to come inside sometimes to catch a breath of clean air. My house is not a clean-room, but it has a filtered air conditioning system that stands between me and the bad stuff outdoors sometimes when things build up and the Air Quality Index shows a high level of pollutants in the air.
If you're not susceptible to these changes in air quality, good for you. But most people are, to varying degrees. Even stalwart smokers notice when the air gets heavy with dust, pollen and smoke particles, and breathing can be actually risky for more sensitive types like asthma sufferers.
What to do? I'm afraid the solution, like so much of life, involves work. To start with, clean your house. Really clean. Use a good vacuum, preferably a hypo-allergenic model, or even a HEPA quality vac, move the piles in the corners, move the couch, move the dog, and vacuum everywhere. Do the walls, too. I'll wait while you finish.
And vacuum your bare mattress to reduce the number of dust mites living there. What are they living on, you ask? Read the Wiki thing in the link. Or don't. Dust mites are icky. Just vacuum your mattress, under your bed, run your bedding through the dryer at high temp once in a while, or, better yet, hang it out on a hot sunny day. Dust mites are like vampires. Sort of.
And once y0ur house is clean, keep it clean. Fry your favorite greasy foods out on the grille rather than indoors. Use a non-ozone air purifier to filter one safe space in your house for you to lurk in on bad air days. Watch the weather thingie for air reports; they're there, but barely. Don't look for them in the shots of the weather lady's legs.
And consider, charming as they may be, that your pets may be part of the problem. Especially if they share your furniture or your beds when you're not looking. And they do, don't they? Don't lie. Of course you love your pets; but they might be as big a factor in your allergies as the ragweed pollen that's out and bothering everyone now.
Respiratory health is not something you can take in pill form. What goes into your lungs can cause you trouble. Sometimes it comes from upwind, from the factory or the city. Sometimes it comes from the scenic fields and woods around your house. Sometimes it comes from the mattress under your sheets. Or from your dog. And if it's coming from inside your house, there's something you can do about it. Those fields may be best viewed through your windows until pollen season is over. Health is an energy issue, as we will see in future posts.

What's That Smell? Quick! To the Shower!

One of the seasonal energy features of summer is: more showers. Not so, say you? Take as many showers in cold weather as you do in summer? Well, let me tell you about my daughters. In their salad days as teenagers they took several a day between them. I, as a hard-w0rking contractor, often find myself in the rain-room more than once a day.
And the electric tank in the basement that supplies my hot water is working overtime to supply all that hot water for extra showers. So add to my energy bill for modest air conditioning comfort the expense of extra hot water for more laundry and showers. And the alternative? EEEEEEEeeeeewwww! What's that smell? See the guy in the photo? Don't get any closer, or you'll receive way too much information. Wait until he's all done and dried off.

What's Mr. Natural's astute, energy-conscious remedy? Well. First things first. Short, tepid showers. You're thinking, you don't know my kids. No, I don't know your kids. But I know how to turn down the settings on my water heater. And you can learn, too. Right here. And be extra careful if your tank is electric; use an insulated screwdriver and don't remove the wireshield. Just follow the directions, do the upper as well as the lower thermostat, and you can become as unloved as a beginning tuba player in minutes. And keep your teenagers away from screwdrivers. Come to think of it, I'll bet they don't know or care where your water heater is located.
Stronger deodorant? Doesn't instill confidence or convey that fresh clean feeling. but you can try. Hippie housefold hint no. 206: apply rubbing alcohol to your pits as you emerge from the shower, then use deodorant if you wish. Don't try this, ladies, after you shave under there. Be warned.
And there's what Kinky Friedman calls the "Waylon Jennings Bus Shower," in which you splash and swab your armpits while standing at the sink. Saves water, job gets done. No fresh, clean feeling, though. Now wipe up the floor.
Between the laundry, hot water and the air conditioning, it's hard to save an energy buck in hot weather. But you can try. Adjust your hot water heater, adjust your air conditioning thermostat, do full loads of laundry in cold water and hang the clothes in the sun to dry. Don't waste energy pleading with your teenagers. Tell them they smell just fine.

Ductless Spllit Air Conditioning - Practically Perfect

If your home has a large open space built around, perhaps, the kitchen, dining room and den, or the newfangled Great Room concept, you can render that space comfortable without sacrificing your windows or paying big sums for some guy like me to install a full duct network for a central system. You can have a "ductless split" system installed, operate it from a handy remote, and cool the large living area of your house in respectable silence.
Window units are noisy and take up window openings. Central systems are the best, but can you afford one right now? Like the incumbent Democratic administration, I favor a considered compromise when all factors can be weighed. I don't favor any single brand, but i do insist that you shop for these essentals: high efficiency, ample capacity, multiple fan speeds, and a good warrantee. Here are some links, offered without partiality for your consideration. Here's a multi-brand site, another one, and a brand or two of the better ones.
To find an installer, you may have to call around, use the Yellow Pages, and ask at the wholesaler's, because not all techs are familiar with the subtle ways of the ductless split. Expect the job to take less than a day, and expect to be cool by dinnertime. The hardest part is tying the electric power into your panel, a process that may require a licensed electrician. Be sure to ask if your installer does the wiring himself.
The thermostat's in the remote, the filter is the washable kind, and the condenser is as energy-efficient as the outdoor unit of a central system, and a bit more efficient than any window unit you can buy. Ductless split is less noisy than window units, slightly more noisy than central, typically.
Here in New England, we have the possible need for home air conditioning, I tell my clients, of about 100 days per year. Most folks use their air conditioning between 40 and 60 days, unless a bust of ralph nader adorns your mantel and you're reading this while completely naked. How much will it cost to get you through the summer? Can you hide in your bedroom next to the window unit? Do you need the whole house cooled and dried to accommodate your teenagers and your expansive tush sticking to your naugahyde recliner? Or somewhere in between? If you'd like to get comfortable in the dining room and huddle around the table like millennial Waltons being cool, and if you're tempted to break out the sleeping bags and have a camping adventure on the family room carpet, you could be enjoying your ductless split system by, say, tomorrow night.

Air Conditioning: It's All About the Water

In summer, no matter where you live, you sometimes wish for a cooler house. "Sultry" is the word they taught us in school for those days of heat and humidity that sap your energy and make you feel clammy and damp. The woman in the photo is using an ancient strategy, moving air across her skin to promote the evaporation of moisture, which removes heat from her body and dries her skin to a more comfortable level. Fans are always good.
But what happens on those days when fans don't work? When the humidity is so near "dew point" that no evaporation is possible? When the air contains so much moisture at its current temperature that it can't receive any more? You can drive to the beach or lake or pool and immerse yourself in water to cool down, or.....
Enter air conditioning, a technology older than you might think, which cools the air in a space and, at its best, lowers the moisture content of the air so that evaporation can remove heat from people and animals therein. Simply blowing air across quantities of ice is an ancient application. Willis Carrier devised a refrigerating device that cooled air using ammonia as a compressible refrigerant in 1902. We now use non-toxic gases in home and auto air conditioners, but the environmental impact of those gases has us looking for the next generation of refrigerants that don't pollute nearly as much. More on that another time.
Here, as I say often, is the secret: any air conditioner that can cool room air to a temperature below its dew point in one pass across its coils will eventually render a space comfortable for people and animals. Moisture drops out of the cooled air, drains off somewhere in a responsible way, and the air now feels more comfortable, breathable, drier, and the moisture evaporating from your skin is removing just over 1000 btu per pound of sweat. Don't think too graphically about the idea of a pound of sweat, but athletes in extremis can shed ten pounds or more from perspiration and evaporation during a game or training session, and marathon runners dread humid days for races because they will sweat just as much but not be able to control their bodies' temperature as well in those conditions. Just like you, in a milder way, on a hot day, entering a room full of cool, dry air. Wonderful. Or unable to find a cool space and wiping away pints (pounds) of perspiration and still feeling hot and miserable.
Today in my zip code it's only 77 degrees Fahrenheit, but it's 95% relative humidity. That means the air is burdened with 95% of the water it can contain at that temperature, and it's unlikely to accept that last 5% without more wind than we have. It's uncomfortable, sticky, still and not going to improve until thunderstorms come later in the day to reduce the humidity. Good day to use air conditioning to dry out the air inside, even though the temperature is not oppressive.
Even if you air condition only one special room in your house (bedroom, tv room, basement den) as a refuge on miserable days, you can give yourself a place to get comfy and avoid the toll of heat stress (the link is a bit lurid, beware). Or you can take a shower to cool down, hug the fan like the young woman in the photo, drink lots of iced stuff, and gripe about the weather to anyone who will listen. It seems to help, somehow.

The S.E.E.R. Predicts Your Energy Future

Do you mind the bad puns in the post titles? The label at left was attached to a new room air conditioner. SEER, or Seasonal Energy Effiiciency Rating, is an industry standard meant to help you compare appliances, specifically air conditioners, as to energy efficiency. A low number means lower efficiency, a higher number means greater efficiency and better performance for less energy.
This Wiki link explains the higher math, but you can get it this way. SEER, in reference to AC units, is the raw number of btu you get from investing one watt for one hour. If you, like me, pay almost 20 cents per thousand (kilo-) watt hours, a SEER 0f 10.5 means you get back 10,500 btu for every kilowatt hour you invest in running the unit. That capacity matches a small room air conditioner, so you can figure you spend between 20 and 30 cents per hour to run your window air conditioner at that SEER. Run it day and night for a week, you've spent perhaps $40 US on average to air condition that room or space. Boring? Only until the power bill shows up.
So the numbers matter as much as the price when you go to the big box store to shop for AC units. You might pay $50 less for a cheaper unit, but how long will that $50 last when a window unit of 9.8 (minimum) EER (category for room/window units) costs 30% more to run than a better one with an EER of 13? The payback on the difference can be measured in weeks, or perhaps a New York minute.
If you install a central (ducted, noisy parts outside, air comes out of holes in floor or ceiling) system, the minimum SEER permitted in CT is 13. And you can spend some more money and get SEER ratings of up to 23. Yes. Almost twice as efficient. And almost twice as expensive. Equipment rated SEER 16 is more reasonable in price, and the energy savings will pay you back rather quickly for your initial investment in better equipment.
If you have large, open spaces in your house (no, I don't mean missing walls and doors, silly), you might opt for a Ductless Split System, in which a single blower unit hangs on a wall and the noisy condenser sits outside. There is no hidden ductwork in the basement and you can control the unit with a handy remote. SEER can range from 13 to 16, and total system cost can be half the amount you pay for a central system. The ductwork I and my colleagues install is efficient and equity-enhancing, but expensive.
Numbers can be so boring unless dollar (or Euro) signs are attached. When you invest in air conditioners, don't wait until it's hot and you're miserable and don't have much money in your pocket. If you can help it. Get a grip, take along a calculator, crunch some simple numbers, tax the salesperson with hard questions about efficiency and capacity, and get more for your money---- not just today, but for as long as you own the equipment. We'll talk more about the different systems in the next post.

Taking It To the Street-- Grid Tie Solar Pros and Cons

The image is courtesy of ABCsolar.com, a commercial vendor, and it explains at a glance the appeal of solar electricity as it is practiced in many states with tax credits and rebate programs. Panels on the roof feed the grid, slowing the spin of that electrical cash register and sometimes even spinning it backward, selling power back to the grid at regionally mandated rates, sometimes identical to retail.
We've weighed in on the topic before, but the discussion, globally and blogospherically (is that a word?), is heating up (intentional pun, not funny but vitally important). Why are the systems set up this way? Here are five points, in descending order of priority, to explain the issues.
One. The grid needs help. Our electrical infrastructure is aging and stretched, and panels on America's rooftops spell R-E-L-I-E-F for the power stations and the distribution network during peak usage hours, which happen to coincide with peak solar production hours.
Two. The math is simple this way. Since home-generated solar electricity can be used by the grid, the simplest calculation is to use the meter in two directions, in and out, and let lower power bills be the immediate reward for an investment in renewable energy for homeowners. Different utilities reward solar power sold to the grid at different rates, and some are capped as to yearly total power contributed from a single system. My local utility, Connecticut Light and Power, uses the Net Metering System, in which the meter simply registers resold power at retail rates. Even I can do that math.
Three. Grid tied systems are less costly. At quoted rates a nominal 5000 watt grid tie system costs the homeowner about $18,000 with all rebates calculated, and some quoted prices are higher. Similar systems involving storage batteries and charging and regulating equipment would cost considerably more, and payback formulas would be even longer than they are now (12-20 years, depending on who's doing the math). The benefit of being able to use stored power at night and in bad weather is dearly bought on those terms. And remember, when the grid goes down, the panels are cut off, even in sunny weather, for safety reasons.
Four. The good news is the bad news. Most of us have very reliable local utilities who keep us well supplied with power, reducing our need for backup systems except in unusual circumstances (storms, blackouts, local line failure). Other countries have much less reliable utilities, and rolling blackouts are a part of life even in other developed countries. The incentive for grid independence, except among those in remote locations and cantankerous old hippies with long memories, is not compelling .
Five. Living with backup systems is a pain. Most Americans worship at the Church of Convenience, so to speak, and planning power usage to coincide with daylight hours while reserving battery power for small loads at night is too much thinking. Battery systems capable of running central air and electric ranges would be huge and expensive, and Americans who spend their days out of the house aren't able to easily plan activities like clothes drying, cooking and water heating.
So---- for now, this is what's possible. Solar power with storage backup is too expensive for modest budgets, too slow on payback to be an attractive short-term investment, and too short on equipment life cycle to be an attractive long-term investment. But the numbers do work: solar power pays, eventually, modestly, reliably, efficiently, philosophically, politically. For those able, in these straitened economic times, to take advantage of it, it affords a chance to be in on the ground floor of something that all of us will eventually join. For now, you might need that home equity as a safety net for your family. First things first. And there are so many other energy measures that are very much within our reach. Let's do those first things first.

It's Not Rocket Science. Photovoltaic Cells Unmasked

A faithful reader has commented on the DIY (do-it-yourself) potential of solar panel construction, and cited a source promising solar panel construction for extremely affordable sums. Here we are, not to debunk the claims of the "You Can Do It With My Special Video" entrepreneurs, but to give a framework of data to help you in your research.
A single solar cell consists of two wafers of highly engineered silicon, joined carefully by a conductive bond, fastened to a supporting backer, with electrical leads. That cell can typically generate .7 volts of direct current power. Connected in a cluster behind a clear glazing, the assembly, or "panel," can be configured to deliver a maximum of 12, 24 or 48 volts direct current while sitting in the sun on your roof.
The catch, and there are a few, begins with efficiency. Silicon responds only to narrow frequencies of light, operates poorly at high temperatures, and seldom delivers, in many lower cost panels, more than 5% to 15% of the potential power of the sunlight falling on it. Here's a NASA link that explains some of the challenges and how they're met. Optical reflectors, wafer stacking, and various cooling techniques can improve panel efficiency up to 20%. In my previous post, titled "3 kwh per square meter per day..." we did some math about the potential of any rooftop to deliver solar electricity, and this efficiency factor has to be part of that math. Even a well-constructed solar panel will only absorb and convert one watt in five in full sunlight.
Once the solar panel is on the roof and receiving sunlight, it needs to talk to a device that converts direct current to alternating current, which is the form of power distributed by utilities and used in your house. The Inverter, as it is called, massages that direct current of some lower voltage into alternating sine wave current at 120 or 240 volts for American homes to use. Voltage may vary by global region. The inverter operates at about 90% efficiency, depending upon a lot of factors, so use that in your calculations.
If your system will be tied to the grid, your panels and inverter will be specified and dictated by the utility. No home-brew systems that I'm aware of can be grid-tied with CL&P's approval. The engineering of the specified inverters carefully matches grid voltage, among other things, and instantly shuts down the system if the grid loses power. This prevents the deaths of linepersons working during outages. It also prevents you from using your system, even if you manually disconnect it from the grid, during an outage.
As of this writing, photovoltaic panels can't be bought at WalMart, except for specialty applications like charging lawnmower and car batteries, and powering tiny landscape lights. Solar panels are available through Home Depot in modest wattages, and they also subcontract installations in some regions. You cannot yet just fill up two shopping carts and be on the grid by sundown, at least not in Connecticut. In some ways the equipment is less complicated than the permits and inspections required by most utilities.
But we're getting there. So, hats off to you DIY enthusiasts, I hope your time comes soon for affordability and regulatory friendliness. Meantime, you can do smaller projects at home, limited only by your purse and daring. Our time is coming, and your questions are always welcome.

Solar Power in CT-- Can I Keep Some?

We mentioned last time that storage is a key issue in the advance of solar electric power as an energy source. In Connecticut the approved grid-tie system features no storage at all.
There are advantages: the installation is simpler and less expensive. The peak output of the panels coincides with Connecticut Light and Power's peak usage during the business day, lightening the burden on the utility to meet peak demand. The relatively straightforward formula of retail power in, retail power out means that photovoltaic output defrays the cost of incoming power at the same price per unit, so the calculation is made right in your meter and on your bill.
Sadly, there's nothing here for those interested in energy independence. You're still tied to the grid, still paying your bill, still subject to rate hikes and only a tiny junior partner with CL&P in the business of powering the state, or your home. Storage is the problem. Batteries are expensive, heavy, not at all maintenance-free, and not perfectly safe. If accidentally pierced, they stink and the contents are corrosive. Batteries are also not quite in the Star Trek category for capacity. For a bank of four batteries (in series, delivering 48 volts, an efficient output for power inverters) capable of powering your house for 14-16 hours at night, you would pay up to $2000; and forget about operating your electric range or air conditioning. Lights, television, refrigerator, computers is about the limit.
Other storage schemes are worth mentioning: hot water, both domestic and for heating, can be heated by solar electric power and stored. Hydronic panels can also be used for the purpose of charging a hydronic storage bank. Thermal mass built into your house can be used to store heat during the colder seasons, and to store "cold" during summer. More exotic applications like storing energy as compressed air or latent heat in a phase change compound are too expensive and complicated to be interesting to non-engineers.
Battery technology is being advanced rapidly by intrepid science jocks and inventors who want to revoltutionize home storage, hybrid cars and electronic gadgetry, and I wish them well. Beyond lead-acid batteries, Glass matt batteries, Nickel Cadmium, Nickel Metal Hydride and Lithium lie technologies that might put overnight storage within our modest collective reach. And utility companies might soften their stance on hybrid storage-grid systems to allow more off-grid independence.
The cruel catch, that rooftop panels cannot be used when the grid goes down, for safety reasons, is a bitter quibble. Imagine yourself sitting powerless under a roof full of potential, with no way to use the power. That's the current state of the industry. Some accomodation between grid safety and home storage will arrive soon, I hope, and the whole enterprise will begin to make more sense for average people. Simply to partner with the utiliity in producing power and spinning your meter backwards is an idea of some appeal. To achieve emergency backup and the possibility of partial grid independence is a much better reason to hock the ranch and load up your roof with panels. I'm holding out for that.

3 KWH Per Square Meter Per Day -- Absolutely Free

My roof, the southerly facing side, measures roughly 800 square feet. That's about 75 square meters. According to the formula in the title, it calculates to 225 kilowatt hours per day. And that's a modest view of the potential of solar power on my rooftop, and yours, and everyone's. Just in New England. In Florida and New Mexico it's almost twice as much.
My house, one in which power is used moderately by American standards, consumes an average of 20 kilowatt hours per day. No electric heat, average range of appliances, lights used one or two rooms at a time, cooking done mostly with microwaves, air conditioning used very sparingly. Twenty kilowatt hours needed, 225 kilowatt hours potential from roof insolation. Twenty needed, 225 available. Twenty, two hundred twenty five. And your roof? And your neighbor's? And a three-family apartment house? And a row of condominiums? Same figures, depending upon roof orientation. And more, usually, as you move south and west, outside New England and our famously changeable weather.
How, then, to collect it? And store it? And share it with other users in the vicinity who have changing needs? It costs about sixty thousand pre-rebate dollars to put panels on the roof, install an inverter and tie it to the grid. Your share would be app. 38,000 dollars, financeable via home equity, low interest loan, or cash if you deal drugs. Or have equity left in your house. Or if you qualify for a low-interest government-backed loan. And then only if you own your home. And the capacity of that expensive photovoltaic system will be only a fraction of the potential of your roof's solar energy load, Less than half. And your daily contribution to the grid will be most of your home's power usage. Only most.
It's a dim picture, but not dark. The tax credits and rebates do not yet put photovoltaic power in the reach of average Americans of average means. And the contractors are charging princely sums for their systems, and the paperwork for the Clean Energy Fund's credits is burdensome, and the systems tend to pay back at a rate that I, for one, won't live to see, and the panels last thirty years in sunlight by a meximum estimate, twenty is a more conservative figure, and the grid doesn't store the energy, it just distributes it among all connected customers.
So many things are not yet quite right about our approach to solar power. But we've begun. and demand does eventually affect supply, and the storage problem will be addressed, and there will be panels on most/every/many/your roof. Soon enough to save the planet? Sooner would be better, don't you think? More next time.

2009 Clean Energy Bill -- Cap and Trade and You

We seldom stray from the home front and the small picture. Today I'm a little excited by the likely passage tomorrow of the Clean Energy Bill. Warts and all, it is a small first step in a long political climb out of denial and into a clear-eyed accountability that will be difficult to reverse once it takes hold. For too long (well before Bush, so calm down GOP readers) we've denied that we might just possibly be fouling the nest. Now a strong Democratic majority is being joined by moderate and progressive Republicans to issue an IOU to the nation and the world on cleaner air and slower climate change.
Is the Waxman-Markey Bill a home run? No. Not even a sliding double. It's a bunt toward first base that we can run out and hope that future administrations/generations will swing away and bring us around to home. The measures (17% reduction in targeted greenhouse gas emissions by 2020, 80% reduction by 2050) agreed upon after much compromise will not by themselves reverse the ominous predictions of scientists convinced that recent and future climate change on this planet is largely man-made. Glacial melt will continue, carbon dioxide levels will still increase, and coal power plant emissions will continue to blot out the heavens, as in the header photo. But the way America looks at industrial emissions will change forever.
So much is missing from the bill. There is no scrutiny of the actual energy and climate cost of the ethanol and bio-fuel industries on which so many people have pinned their hopes. There are no real jaws to close upon persistent offenders: indeed, "cap and trade" means that dirtier industries will be purchasing "carbon credits" from cleaner industries not needing them, and the sale of these "pollution indulgences" will be mostly unregulated. Trouble brewing there, I'll wager.
But, we and Al Gore are exhilarated by this first step, out of proportion to the actual impact of the bill. Due credit to Bush One for signing the U.S. into the Kyoto Protocols in the early 90s, but no piece of legislation since that one has had the same impact, for this one reason: the cat is out of the bag, and, having admitted to ourselves that the job is before us, we are unlikely to retreat again into the darkness under the pillows.
Legislation is boring to read, and I'm only linking to a "talking points" discussion by the bill's authors here. In order to give the bill a chance at passing, Waxman and Markey pulled back from the bold early drafts in order to court bipartisan support. In the event, only eight Republicans in the House voted for the bill, and all were promptly savaged by staunch conservatives, who favor increased investment in oil and gas for America's energy future.
The Clean Energy Bill is touted by its supporters to be economically positive, creating jobs and provoking the kind of technological stampede for which Americans are famous when they get hold of an idea. I'm imagining home-brew CO2 sequestering devices being whipped up in garages, and complex climatic models coming out of college dorm rooms. Heaven knows, that's how Hewlett and Packard and Gates and Allen, respectively, started out to change the world. The currency for which America has long been most famous is entrepreneurial innovation. The Waxman-Markey Bill is a big kick in the butt for inventors, venture capitalists and investors looking for reasons to come out of their economic bunkers and start generating life-changing ideas again.