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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.
Forty states have laws allowing individuals to do this, and many of them offer subsidies and tax breaks for people who do.
Tell that to the boy scout who tried to build a reactor in his backyard.
Push Button, Receive Bacon
When talking abt non-conventional sources of energy, solar power technology is yet become economic. I would rather install a wind mill on my roof instead a solar plates.
while back here in third world countries we use other non-conventional ways to save on energy bills like
Bribe the Electricity Engineer or
Tap electricity directly from pole without any meter
Eclipse PDE and Me
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.
In the Netherlands, farmers who plant crops in greenhouses always have petroleum gases driven generators to warm the greenhouse in the winter. In summer, these generators feed back into the grid.
8 of 13 people found this answer helpful. Did you?
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 people behind the current Solar Living Institute (www.solarliving.org) have been doing stuff like this for probably over 30 years, back when it was called "Real Goods", which sold solar electric panels and prided itself on "taking people off the grid".
They sell a book Solar Living Source Book (now in its 12th edition) which tells you how to take your home off the grid using solar panels, plus they offer courses http://www.solarliving.org/workshops/. They also run the Solar Living Center, which is a self-sustainable solar energy building/store/headquarters in Hopland, California.
The odometer only had 3 digits. Why didn't they just run it forward till it turned over?
Surely I wasn't the only one who was bothered by this.
Can you be Even More Awesome?!
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
You also need the right gear. It is expensive at the moment, but it wouldn't be if everyone was buying it.
It's not a million miles away from the cheap inverters and UPSes you can buy. One important point is this - it must have an incoming mains supply to work. If there is a power cut, it will shut down, and most aren't smart enough to just disconnect from the grid and leave you on standby power. Why? Well, because it needs a phase reference for the incoming mains, and if the power goes down it has no way of knowing what phase it's going to be when it comes back. 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.
What is to prevent people from storing electricity (in batteries) during off peak hours and then selling it back during peak hours and generating a profit?
"I'll just chip in a bit for RedHat: I actually have that installed on my university machine." - Linus, '95
This is far from an impracticable technology. In the days of wooden ships, the Dutch used to buy English ships that had become waterlogged (yes, they do...) fit them with windmill pumps and continue to use them, just letting the wind keep the bilge dry.
To be really clever, if you manage to set up a windmill pumping system, run it in parallel to the electric pump with a simple rotation sensor (two microswitches and a simple cam on the shaft, linked to a timer circuit) so that when the wind stops, the electric pump starts.
Pining for the fjords
I'm surprised the US hasn't been doing this before, I think we've been able to do this for years in the UK and it's a pretty obvious development really.
;-)
I'm not sure how well Solar Power works here though
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
Every time an article like this comes up, people are nice enough to point out problems with solar (gunk to create, $$ to invest, wears out). Still, I have to say the idea continues to be exciting
The appeal comes with the similarities to computer evolution and balance (mainframe/personal) and the internet (grid computing). People can keep telling me it isn't worth it or will never happen (or will be super-inneficient), but I'm always going to hold out for that internet-like energy grid. All your Googles and p2ps working together...figure out a way to sell ads over power and maybe you'll get free power from Google itself. Hmmm...maybe I should patent ads over power lines before it is too late.
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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.
Is it worth lobbying for a industrial AC/DC rectifier in each house at the meter.
.2 volts in 40 feet.
.2 volts drop. Don't forget the current in a 40 foot length travels both ways on 2 conductors, so figure it for 80 feet.
No. Do the math. From the post it looks like you are advocating a 12 volt system for the house. Right now a 20 amp breaker feeds a 12 AWG wire just fine and you can plug in a 1500 watt hair dryer in the bathroom which is maybe 40 feet from the meter. At full load, the voltage at the outlet may drop a couple volts so you are talking 12 amps current at 2 volts in the wire or 24 watts lost in the entire length of wire.
Now the 12 volt version. From 120 volt to 12 volt at the same wattage (Volts * Amps for a resistive load) you will now need to draw 120 amps instead of 12 for the blow dryer for the same 1500 watts. If you were dumb enough to try using the same 12 AWG wire the 2 volt drop is now 20 volts. OOPS.. We seem to be short 8 volts in the negative direction to get 120 Amps to the bathroom outlet at zero volts. Lets see if it were possible the 20 volt drop in the wire at 120 amps would be 2400 watts of heat in the 40 feet of wire. Can you say HOT!. Maybe we need a larger wire size. Maybe a size big enough to handle the original voltage drop of a couple volts. Our original setup at 120 volts has less than 2% voltage drop. At 12 Volts we now have a little under 20% voltage drop. Hmm we need to go to even bigger wire to reduce the voltage drop to less than
You do the math. Find a copper wire table and find out what AWG wire is required to handle 120 Amps with only
When you are done with the math you will understand why we use 120 volts and some countries use 240 volts. You may get electricuted in an accident, but you don't need welding cable for your hair dryer.
My 1KW inverter in my car uses Welding cable for leads and the length is kept to under 3 feet total to keep the voltage drop within limits.
The truth shall set you free!
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.
I can make about $15 after a big mexican dinner.
Any rational utility will only pay for at most, the avoided cost of the power, maybe 30% of the retial price. Anything else is madness.
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.
In greece, after the new (2006) law, you can put solar panels to your house and get paid from the electric company (the only one) for selling them electric power. You get paid 50 cents for every KWh you contribute to the network, since the selling price from the electric company is 7 cents per KWh. This is possible cause to the new law that want to promote the use of clean energy.
Yeah, but the odometer displayed European miles, which are actually 0.002 lightyears each. Good luck getting even the second digit to turn over. *snort*
If a typical Nuclear power plant costs a billion dollars, what would happen if instead the money was spend on solar panels for individual homes, in the form of tax breaks and rebates for homeowners that put them up? Remember, economies of scale and distribution of the grid and all those other benefits too. Seems like a no-brainer to me...
Reality has a liberal bias
To see why I'd advise against continuing to invest in nuclear power see http://mdsolar.blogspot.com/2007/01/why-renewables -displace-nukes-first.html.
But if you think that analysis is flawed, you can still work out a way to invest even more by switching to solar personally. Look at the calcualator at http://www.jointhesolution.com/mdolar for a low balled savings estimate (2.2% estimate of annual electric rate increase I thing) and 9% return on the invested savings.
Solar panels are now good for about 30 years, and if you rent from us, we handle the disposal and leave your roof in good shape. Note that since they are still solar grade silicon, they only need to be recycled. They are worth about $25/kilo as raw material.
Welcome to KCAL 9. We're sorry we had to cut away from this evening's high speed pursuit but we have received word that Ventura is experiencing scattered sprinkles. Johnny Mountain is down in the trenches, reporting from the eye of the storm. We'll hear from him after this break, if he's still alive!
Being able to store your power onsite first-before it gets to the net metering phase, is a huge benefit and one of the primary good reasons to have onsite power production. We've seen just a ton of news stories over the past few years of whole regions going down from storms, etc. Heck, there are still a lot of folks in the midwest struggling with that now. Think of it as a whole house (or however many circuits you have activated, you can pick and choose) UPS system then it makes more sense. And that's the good part of home solar, you can do both. From my experience, on a good sunny day by around 1:30 PM or so your battery bank should be pretty full if you have sized your system properly, then it's gravy after that, all afternoon. You are still sitting on enough juice to run everything for at least a full day, and your meter can be running backwards then if that is the set up you have.
You should look at the tariff book before saying that 18c/kwh is high. Here's the price where I live:
Baseline: 11.34c
101%-130%: 12.98c
131%-200%: 22.94c
201%-300%: 32.14c
over 300%: 36.96c
Baseline usage is 11.9 kwh per day in summer, 12.6 kwh in winter.
For me, before I installed the panels I was regularly running into the "over 300%" category, and that was one of the reasons that solar made sense for my particular situation.
Also, I didn't spend $65k on the installation, I spent $31k. If you take out a loan for this amount, you can pay it back entirely out of the electricity savings.
Don't take my word for it - the State of California has a very comprehensive on-line worksheet that will calculate how much energy an installation will generate based on your location. It will also give you the numbers about how to finance it, including accounting for lost opportunity cost by tying up your money in the panels. I reviewed the numbers after a year and I actually generated about 2% more electricity than the calculator said I could expect.
I didn't install panels to sell electricity. I installed them because I liked the idea of generating my own electricity, and it because it made good financial sense for me.
You see the economics as dreadful. I (who actually did the math very, very carefully) see the economies are a very good deal. The deal is only sweetened by the reduction in greenhouse gases that my installation triggers.
Frankly, you remind me of a person arguing that it's a bad idea to vote. You are only one person, you can't possibly make a difference, and think of all the lost money with people driving to polling stations and waiting to cast their votes. All true. And all very wrong.
There is a company using net metering laws as a business model to offer homeowners free solar panel systems. Basically you rent the solar panels from them for the price of the electricity they generate, based on your current utility rates and locked for however long you sign up for (1, 5, or 25 years). I really hope this succeeds as it is the first really workable business model for mass solar adoption that I have seen. Check it out here:
http://www.jointhesolution.com/makepower
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...
No you didn't.
Ironically, the word ironically is often used incorrectly.
Braking with the clutch out and in gear prevents wheels locking up if driving on slippery roads. If the clutch is in, nothing is forcing the wheels to spin except ground friction, and the wheels can skid more easily if there is very low ground friction (ice/snow). If the clutch is out, and transmission is in gear, the engine is turning the making the wheels spin. Been there done that.
- High Tech workers, please say NO to Union Carpenters, their Union sees fit to control our compensation.