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Running Your Electric Meter Backwards
kog777 writes to note a story in International Business Times about "net metering," or generating your own power without disconnecting from the grid. Forty states have laws allowing individuals to do this, and many of them offer subsidies and tax breaks for people who do. From the article: "When the sun shines bright on their home in New York's Hudson Valley, John and Anna Bagnall live out a homeowner's fantasy. Their electricity meter runs backward. Solar panels on their barn roof can often provide enough for all their electricity needs. Sometimes — and this is the best part — their solar setup actually pushes power back into the system."
With a Ferarri when you stick it in reverse.
Task Mangler
Err, this has been mentioned countless times. I really fail to see how this story adds anything. Yes, you can put power back into the grid and get paid. This is not new, and this is hardly a little known fact.
I live in Southern California, and one side of my roof faces south, so I should be a prime candidate for this. However, I have some concerns about actually doing it. For one thing, when we bought the house, 10 years ago, the sellers were just in the process of replacing the roof, and while they were at it, they removed the solar water heater for the pool. If you figure we have 15 years left on this roof, I have to wonder whether an expensive photovoltaic system will end up going the same way as the solar water heater. Another question in my mind is the uncertainties related to the craziness California has been seeing in electric rates, as well as uncertainties about when is the right time to buy photovoltaics, given that the technology is advancing rapidly. And then there are all the other things that might be easier and more practical than installing solar panels. I replaced a bunch of incandescent bulbs with compact fluorescents last month. I've never been able to get power management to work properly on my Ubuntu box. One of the big electricity hogs in our house is the pool pump, and there's not much you can do about that; if you don't pump long enough on the pool every day, it turns green.
Find free books.
This is more widespread than you realize. Aussies have been doing it for a couple of years now. Just the thing for a desert country where it seldom rains:
- cold-beer-is-on-the-house/2004/12/06/1102182229401 .html
http://www.smh.com.au/news/National/Where-the-icy
Back in 2003 I decided the time was right to go green. At the time I was paying about $2900 a year for 15,500 KwH, and I figured I could make the money back in a reasonable number of years. After many discussions with local solar installers I picked one and in December 2003 I had 48 panels, each 60 inches by 30 inches, installed on my roof and three inverters on the side of the house to convert the DC output to standard household AC.
The panels generate approximately 7.5kW AC (8.8kW DC). The total cost was $65,000 but with a grant from the State of California and State tax credits, the total cost was reduced to just over $31,000. Since then I have been paying only the minimum price for electricity service (around $5 a month) to cover the cost of the meter rental. As electricity rates have increased a bit (and no doubt will continue to increase) I calculate that I will recover my costs approximately 8 years after installation, and I will then start to save money. The life of the panels should be around 30 to 40 years
It's worth remembering that you need to make certain your roof is good for the years the panels will be operating, so for some it will also mean installing a new roof first. That wasn't an issue for me as I have an ornamental metal tile roof that should last much longer than the panels.
Essentially, I use the power utility as my batteries - during sunny days I generate much more electricity than I use and the excess goes into the grid, and then I use power from the grid on rainy winter days and during nighttime. I get credited for electricity sent to the grid, and yes, the meter really does run backwards.
One neat trick is that I don't have to generate the equivalent of all the energy I use to break even. I'm on a utility company plan where the electricity I use during peak summer times (noon to 6pm) is very expensive - around three times normal rates - but off-peak usage is about 70% of normal rates. But I get credited at the rate in place at the time of day the electricity is generated. Because my installation generates the majority of the electricity during the peak times, I get credited for those KwH at the high rate and when I need to use electricity at night I pay the reduced rate. As an example of how effective this is, last year I generated 12,400 KwH and I also used 3,600 KwH from the utility company. But at the end of the year I had a credit balance of $380.
There's one gotcha there - if you have a debit balance at the end of the year, you have to pay it. But if you have a credit balance, that gets lost. Ideally you want to generate just enough electricity so that your adjusted balance is zero, but that's pretty hard to judge. In any case, you want ample extra capacity just after installation as the panels reduce their efficiency by about 0.5% to 1.0% per year.
Back in the 'good old days' you could hack the meter and switch the wires around so that the meter would run backwards, even though you'd still be getting electricity. A one-time friend of the family did this in a shop he owned. He figured he'd switch it, operate for a week on, week off, so the bill would be low, but not too low. Unfortunately he forgot about this arrangement and the meter showed him to be $1000+ in 'credit' with the electricity board saying they were going to be visiting in a week or so. Panic ensued, and he bought a bunch of electric kettles and rigged them up 24/7 to suck juice from the grid to get back into the red.
The consumer is offered two choices from the utility:
A. peak rate at $0.40/kWh and off-peak at $0.20kWh
or
B. fixed rate at $0.35/kWh
Now two neighbours sign up for the two different rates, and start their own little energy trading:
Off peak, Neighbour A buys at $0.20 from utility and sells to neigbour B for $0.35. B resells to utility.
During peak hours, Neighbour A buys from B at $0.35m and sells to utility for $0.40.
With a 400A service, they can 800,000kWh a year and make a profit of $80k!
Have fun
don't cut it off www.mgmbill.org
My dad had a friend a while back that did this, I think maybe in Oregon or Washington, but I don't recall. He had a large property with a decent sized stream running through it, and set up a water wheel. It generated A LOT more power than he used, so he was constantly pumping power back into the grid, which his electric company paid him for, at something like one fifth of what he would pay for the electricity if he was drawing it. The startup cost wasn't that high, as he was an electrician and set it most of it up himself, and was way more cost effective than solar panels at the time (I don't know if that is still true, this was 10 or 15 years ago). He wasn't just saving money, but actually turning a profit of a couple thousand dollars a year.
I think some time later the regulations might have changed and the power company would no longer pay him, but at least he still had electricity that was essentially free.
Imagine if your inverter is pushing out the full -120v when the incoming mains comes back at +120...
It would be possible to build an inverter that would disconnect the incoming mains supply in the event of a power failure, and "slip" the inverter until it's in phase before dropping it back in, but you'd need something like a 100A contactor for that to work.
Actually, they drop it because grid-tie inverters are REQUIRED to disconnect from the grid when the grid goes down. This is to prevent backfeeding the disconnected island and frying a lineman who's trying to fix the downed wire for your block and thinks the lines are dead when YOU kept them live. (Those pole-pig transformers work just FINE in reverse, so a lineman might grab a line with 12,000 volts on it and a couple kilowatts to keep it that way while he's dancing and trying to breathe.)
Now the EASY way to do this is just to monitor the frequency and voltage, and shut the inverter off when it goes out of spec (meaning the grid is probably dead and the line only looks hot because of the inverter backfeeding it).
For a couple grand more, in the case of some good inverters that are designed for it (such as some of the Xantrex models), you can add a box with a relay, a phase-difference monitor, and a subsidiary "brain" board (or get an inverter with the function built in). (Actually the box in question usually also has the line monitoring circuit and combines with inverters that are otherwise stand-alone non-grid-tie.) That box will disconnect the inverter-and-keepalive-lodds from the line and let it keep going during an outage, then tell it to drift phase until it matches and hook it back up once the grid is back and has stabilized.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
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All you have done is pre-paid your electricity for the next 5-10 years
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60 months worth of your electric bill, call it an average of $100 a month, is $6,000. If you "pre-pay" that by rolling it into your home loan ("Build me a house and make sure it has a pool and solar power!"), it will end up costing you more (rough guesstimate is $7,300). If instead of buying photovoltaic cells you buy shares in your local electric company, you'll get about $120 to $240 a year in dividends (power companies often have a 2-4% yield), and your while your photovoltaic cells depreciate every year and require maintenance, your shares will probably appreciate and you'll never have to patch them up. (You'll have to pay the electric company for those 10 months of the year that dividends don't... then again, you get the security of knowing you'll never have to pay them extra just because its cloudy.) When you move in 15 years, rather than uninstalling or replacing them at your expense, you can just sell them and take your profits.
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In the end, I think the choice is whether you want to help make the world greener, or you just plain don't give a rats
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I don't give a rat's hindquarters for Green theology but don't mind conservation. Thats why I buy shares in companies which own nuclear power plants. Its cleaner than solar and has economies of scale. Yes, I said cleaner than scale: the energy cost from constructing solar panels keeps them net-energy-negative for about a decade (!) and when they die out after just over a decade (!) you have to dispose of them, and per megawatt hour generated you'll have to dispose of a heck of a lot more solar panels than radioactive waste. I don't invest in solar companies because at the moment they still haven't licked the whole "Making our products net energy producers" problem and until they do my only hope to profit from that investment would be hoping solar's massive government subsidies continue and expand. While I think that is certainly possible, I feel that if the current or a future administration wants to dump a couple billion into the solar industry, my nukes will get a similar largesse.
Sidenote: If you have an aversion to nuclear power, I understand and accept that. I don't eat meat on Fridays in Lent and we can both agree that our separate faiths are mutually harmless. One piece of advice though. Spend your money on a decent job of insulating your house -- you'll require less kwh from the grid, and on a per-dollar basis you'll save more kwh spending on insulation (and installation) than you will on buying solar power.
Help poke pirates in the eyepatch, arr.
The problem is that you would be getting paid retail value for the power you are selling to the company. Looking from their point of view, you should actually have two meters, one to meter the power you buy from them at retail price, and another to meter the power you sell to them, at whatever price they buy power. Otherwise, if everyone started generating their own power part of the time, the power company would go bankrupt.
I've looked at the cost of photovoltaics, and the ROI, and my conclusion was that I'd rather go with a wind turbine. The same thing applies - in areas that allow it, your excess power runs your meter backwards and the power company pays you for it. A pretty good selection of small scale wind turbines can be seen here. Of course, if you have 5 acres like I do, you can dream about these little darlings that start at 1.5MW power generation and move up from there. No serious zoning issues if you are out in a rural area, and your ROI is as low as 3-4 years - assuming no unusually high maintenance costs and that the power company will pay you a decent rate per kWh not some pittance.
Staying at home and working is not so bad. I didn't get this from slashdot but it is an excellent resource that I use for targeting my marketing: http://www.dsireusa.org/
Click on a state, look under Rules, Regulations & Policies for net metering rules.
You can also look on my website http://www.jointhesolution.com/mdsolar so see utility rates.
Click on the map then click on a state. If you see the utility listed you can do net metering there.
I think Bill Gates has one with three digits, and it's in kilometers, not miles. The car was custom built, and they explained there wasn't room for more digits. Gates, of course, said (and who doesn't see this coming) "No problem. 640k should be enough for anybody."
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