Monday, November 30, 2009

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.....

Friday, November 20, 2009

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.

Sunday, November 15, 2009

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......

Wednesday, November 11, 2009

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.