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You don't HAVE to ask them permission.

Anyone running a grid-intertied home power system[PDF] (typically photovoltaic, but wind and hydro also apply) with battery storage has had this ability for years. If they're not producing enough of their own power to meet demand, they buy from the grid. Since the process of rectifying, storing, retrieving, and reinverting the power has some efficiency losses, buying power at off-peak times isn't always a no-brainer, but it's frequently economical to do so.

And of course, even if you don't have a battery-based storage system, scheduling your laundry to run in the middle of the night is smart. You get cheaper electricity (assuming your utility meters it that way), and you ease the burden on the wastewater treatment system by not dumping your effluent into it during peak demand periods.

Have you ever seen http://www.homepower.com/ magazine?

There's a very nice reasearch piece on that at Homepower Magazine:

http://www.homepower.com/files/birds.pdf

long-and-short: Now-a-days it is mostly a myth.

There are various solar ovens you can purchase or build. One interesting one I saw was built into the south wall of the kitchen. Basically a large insulated box that had glass on the southside and the oven door on the kitchen side. It was only good for one quick cook from around 11 am to 1 pm, but still enough to toast a chicken or whatnot. The stand alone ones work well ( I have a commercial model you just set oputside on the picnic table or whatever), you just have to go turn them to face the sun occassionaly, but that could be somewhat easily automated with some photocells and a small turntable, or just a mechanical timer and some good maths for that matter if you wanted to. a lot of times I just default to "biodrive"-me_ to do simple tasks if it's feasible and easy, the K.I.S.S. principle.

One bit of advice, you just cannot beat insulation on payback and useability. Look into the "superinsulating" concept of structure design. It's very googleable. You shoot for R-55 floors walls and ceiling, and you can almost eliminate much in the way of heating or cooling, you can get it down to a ridiculous small level to maintain a decent comfort zone. The one house I worked on, back during the OPEC oil shocks, as a serious retrofit, we built interior walls around 6 inches away from the existing walls, then used blow in insulation to fill it up, then normal drywall to finish it. The old windows got replaced with triple panes, and much work on the various cracks, etc to make it tight. It's an *amazing* difference. In a lot of cases, just normal lightbulbs and inside cooking and whatnot is sufficient "heat" in the winter, with the furnace only turning on occassionally. similar with the cooling, the AC just won't run that much. dollar for dollar no other technique can touch it. Insulation is not sexy, but man it works! It's a serious "silver bullet" alternative energy technique that isn't being explored much. People "get it" woith high MPG cars, they can understand that, but with their homes they will pop for a long term mortgage for some place that is the energy gashog equivalent of an SUV with fouled plugs running on flat tires uphill. I have no idea why this is so but it sure is. And the banks will give them a note for it! R-18 maybe cut the mustard back when oil was a few dollars a barrel, but not now.

The whole subject is fascinating, it's quite possible nowadays to not only have a totally energy self sufficient home, but also get a check back from the electric company every month, or at least bank kilowatt hour credits.

If you are going for active solar, now is a good time as you can combine a lot of tax breaks with tying the installation into your home note long term. Most folks go for a hybrid system, solar PV, thermal, wind charger, fuel generator, then a grid tie. It just depends on your location what is practical or not. You are about covered for juice then with any mixture of the systems, and combine that with a good sized battery bank. having a whole house UPS system is quite spiffy...... And greenhouses are just *neat*. I was just up in ours looking at the tomatoes and peppers and cabbages and whatnot..... while the outside garden is now mostly gone by for the winter. We even have some roses blooming in there and some tropicals, but I don't know if the heavy tropicals will make it this is the first winter and we don't really want to artifically heat it, just cost too much and I don't have that other composter heater built yet, just too many back burned projects behind now. What some guys have done is combine raising meat animals inside the greenhouse with plants, like chickens or rabbits. The animals throw off good heat 24/7 and can eat a lot of the vegetable scraps. You can put tanks for fish as well and use the water for thermal storage. Lotsa neat stuff you can do. If you go the small meat critter route, you can use their, uhhh, how do you put it, their "exhaust", heh, in a methane digester to get burnable gas.

good website for you (dead tree magazine as well)

http://www.homepower.com/

you'll go nuts there, double heh

Depending on the circumstances, you might be able to get stuff down there for less than in the US. If you can't power your machine directly off of the battery, use a higher battery voltage (ie, 24 or 48 volts for example) so you can save on wiring, unless your setting up the grid intertie (where you use the grid as a battery and just get the panels and the inverter). Be sure to get an actual utility interactive inverter. Don't just connect any inverter to the grid or bad things will happen. If you're looking into just being independent of the grid but still want an inverter, get a sine wave inverter, as everything will run better. (I mean it, don't skimp on this! You can actually fry stuff with a square wave or "modified sine wave" inverter, despite what some people might tell you!) Yes, it is a bit more expensive, but everything works out better in the long run. For more info, check out Home Power Magazine. Good luck, I wish I had that much sun! Have fun, stay safe, and remember to fuse.

OK, I can comment a little bit on this. First of all, there is a hosting company that claims to run entirely on renewable energy (solar, wind, they don't get to specific on their site), SolarHost.com. I've never used them, only read about them.

As for running on solar power (or wind), what you want to consider to start with is how much power the box draws, and how long it will run. The best thing you can do is conserve what you can; it will save you on overall system cost. If it's a workstation, pick one just as big as you need, and don't go overboard. (I'm typing this on my dual AMD MP box, which yes is overkill. But in case anyone's interested, with both CPUs at 100 % doing some Maya rendering among other things, it draws about 250 watts.) A server is the same way, but you'll usually want to leave it on all the time. You can take many conservation measures, like making it a headless box and minimizing the hardware involved. My Gentoo Web/Mail/MySQL server at home is a 1 GHz Via board with 256 MB Ram, and the 12 volt car power supply. All I have connected to the board is a hard drive; I disconnected the CD-ROM when I was done installing. At 12 volts, it draws roughly 30-36 watts (~3 amps).

Going the 12 volt route is nice, because then you don't need an inverter to power the box. Assuming it draws 35 watts 24 hours/day, that comes out to 840 watt-hours a day (you get watt-hours by multiplying watts by hours). Obviously, we're going to want to use a battery so our server can run at night. So, we multiply by 1.2 to compensate for the power lost here, and get 1008 watt-hours (1.008 KWH). Now, assuming we want to do this entirely with solar, we need to figure out how much sun is available in the area. Go here to figure out how many hours of sun you get a day. Where I am, in New York State, we get an average of 2.5-3 sun hours a day throughout the year (keep in mind, this is "full sun" so the panels will be putting out power at different light levels, though well stick with this figure of the sun hours). Let's use 2.5 sun hours to be safe. To produce 1008 watt-hours, we divide 1008 by 2.5. The result is that I would need 403.2 watts of solar panels. Four of these will be about right, putting out 115 watts each or about 460 watts, leaving a bit of a buffer. The price of the panels alone would be $2,060. You'd need batteries next, with enough capacity for, let's say, 3 days without sun. That means they have to be able to hold 3.024 KWH at 12 volts, or 252 amp-hours (3,024 watt-hours divided by 12 volts). If we drain the battery (assuming a deep-cycle led-acid battery) down all the way, we'll damage it. The minimum should be 20 percent. To make sure they last long, however, we should go with something more along the lines of, say, 35 %. That means we should plan for a battery bank with a capacity of about 390 amp-hours. A pair of the L-16 HCs found here should work. Then you'd need a charge controller of about 50 or 60 amps. Not including wiring, labor, fusing, shipping, or the server itself, the cost comes to about $3,116. This is to run a 35 watt load 24 hours a day.

Believe it or not, small-scale renewable energy is in fact quite popular. A lot can be done with the power generated by that system; you could probably run a small apartment with it (assuming no heat with electricity, and that said apartment does not contain the server :-)). Most people don't run a server all the time, so something like this works out. Running an average-sized house, after some slight conservation (not using electricity for heat, using compact floursecent lights and LEDs, and just remembering to turn stuff off when not using it), the total is usually about $20,000 to $30,

From the article, LEDs produce twice as much light as a regular 60 watt bulb. I'm really not sure how to think about all of this. If LEDs produce twice as much light as a regular 60 watt bulb, how does that make LED lights better than compact fluorescent bulbs, which can produce four to five times as much light as an incandescent bulb of the same wattage?

Warning it's a pdf, Here is a lighting test, which lighting technology can produce the most light for the least power? The hands down winner is the light emitting diode (LED) which makes three times more light per watt than a compact fluorescent and 30 times more than a standard incandescent.

Can you point me to documentation of LEDs being 3 times as efficient as fluorescent? What I have mostly seen is that they are about the same efficiency. With the LEDs being about 3 to 4 times the cost.

Warning it's a pdf, Here is a lighting test, which lighting technology can produce the most light for the least power? The hands down winner is the light emitting diode (LED) which makes three times more light per watt than a compact fluorescent and 30 times more than a standard incandescent.

That's wrong about LED lights If you thing CFLs are better than LEDs I suggest you read what "Home Power magazine, which has some excellent articles on living off the grid, says:

Warning it's a pdf, Here is a lighting test, which lighting technology can produce the most light for the least power? The hands down winner is the light emitting diode (LED) which makes three times more light per watt than a compact fluorescent and 30 times more than a standard incandescent.

That's wrong about LED lights If you thing CFLs are better than LEDs I suggest you read what "Home Power magazine, which has some excellent articles on living off the grid, says:

Warning it's a pdf, Here is a lighting test, which lighting technology can produce the most light for the least power? The hands down winner is the light emitting diode (LED) which makes three times more light per watt than a compact fluorescent and 30 times more than a standard incandescent.

White LEDs are twice as efficient as most incandescents. However, compact fluorescents (CFLs) are twice as efficient as white LEDs.

Guess I have to post this again to clear up any missunderstandings about CFL and LED lights: If you thing CFLs are better than LEDs I suggest you read what "Home Power magazine, which has some excellent articles on living off the grid, says:

Warning it's a pdf, Here is a lighting test, which lighting technology can produce the most light for the least power? The hands down winner is the light emitting diode (LED) which makes three times more light per watt than a compact fluorescent and 30 times more than a standard incandescent.

White LEDs are twice as efficient as most incandescents. However, compact fluorescents (CFLs) are twice as efficient as white LEDs.

Guess I have to post this again to clear up any missunderstandings about CFL and LED lights: If you thing CFLs are better than LEDs I suggest you read what "Home Power magazine, which has some excellent articles on living off the grid, says:

Warning it's a pdf, Here is a lighting test, which lighting technology can produce the most light for the least power? The hands down winner is the light emitting diode (LED) which makes three times more light per watt than a compact fluorescent and 30 times more than a standard incandescent.

CF lamps are at least a factor of 10 more efficient than LED's even the highest output led's you can buy. If you are looking for efficiency I strongly suggest you do what those that live ofgf grid or on DC power do.. they use Compact Flouresent or cold cathode. I can produce 100time the light with 6 watts of electricity than you can with the most advanced led lighting system available..

If you thing CFLs are better than LEDs I suggest you read what "Home Power magqazine, which has some excellent articles on living off the grid, says:

Warning it's a pdf, Here is a lighting test, which lighting technology can produce the most light for the least power? The hands down winner is the light emitting diode (LED) which makes three times more light per watt than a compact fluorescent and 30 times more than a standard incandescent.

CF lamps are at least a factor of 10 more efficient than LED's even the highest output led's you can buy. If you are looking for efficiency I strongly suggest you do what those that live ofgf grid or on DC power do.. they use Compact Flouresent or cold cathode. I can produce 100time the light with 6 watts of electricity than you can with the most advanced led lighting system available..

If you thing CFLs are better than LEDs I suggest you read what "Home Power magqazine, which has some excellent articles on living off the grid, says:

Warning it's a pdf, Here is a lighting test, which lighting technology can produce the most light for the least power? The hands down winner is the light emitting diode (LED) which makes three times more light per watt than a compact fluorescent and 30 times more than a standard incandescent.

And as these lights are not particularly energy efficient compared to CF, their utility might be limited.

By "these lights" do you mean LEDs? Because if you are then you're wrong as LEDs use something like 1/5 the power of CFL, Compact Florescent Lights. which themselves use 1/4 the power of incandescent lights:

Warning it's a pdf, Here is a lighting test, which lighting technology can produce the most light for the least power? The hands down winner is the light emitting diode (LED) which makes three times more light per watt than a compact fluorescent and 30 times more than a standard incandescent.

I have been impressed with the LED lights over florescent or incandescent. The subdued lighting is fine with me and the energy consumption / bulb longevity is the best part. When my wife and I move (build a house), we will go 100% LED.

Currently I use CFLs, Compact Fluorescent Lights, 12 and 15 watt bulbs that produce as much light as 60 and 75 watt incandecent or "regular" bulbs and last up to several tymes longer. But LED lights bulbs I found out about a few months back use much less energy and last a lot longer than even CFLs. I'd like to, and am working on plans to, build my own home and when I do I want to be off the grid, probably powered by solarand wind genies. Or maybe fuel cells. So I'll be using LED lights myself.

Power in the future isn't going to be wind, geothermal, etc, because it doesn't produce enough power.

Not enough power? Current solar cell technologies (available to the average consumer) can achieve ~15% efficiency. This is at "full sun," which is rated at 1000 watts/square meter. There are even more efficient technologies used in satellites, etc. There is still a lot of room for improvement, but it is not too far off. Many people already supply all the power they need for their home with solar and other renewables. (Check out Home Power for more on that.)

Of course there's no way this'll ever happen over night. But it is a good thing to work towards. Greater production of the renewable energy technologies would lead to more innovation, and new jobs. The US and other countries should work to phase in something like this over time, rather than just building a bunch of nuke plants.

I personally don't see a problem with this. What with modern technology, it seems like we should be able to build nuclear power plants much safer and more efficient than anything in the past.

I would tend to agree. However, I was reading an editorial in the latest issue of Home Power magazine which stated that nuclear power plants are not as economical as we have been lead to believe. The government (read U.S. gov) subsidizes some aspect of the operation to make it profitable.

I have never heard this before and the source is certainly not without its bias so I am somewhat skeptical. Anything that isn't strictly a renewable source to them is bad.

here, homepower magazine

http://www.homepower.com/index.cfm

you will like this mag if you have never seen it

This is the sort of project that alternate energy folks do all the time, ie, using battery backups then to the house circuits. It is common. Whether the original juice is from solar PV or wind gennys or microhydro, fuel generators-or the grid,or a combination of the above, which most enthusiasts have, the wiring is very similar. They have a nice searchable archive of all their past articles, and you can review inverters, grid ties, separating circuits, charge controllers, etc.

With that said, with just the one UPS, I think just plug it in and plug your computers to it like normal. HOWEVER, what you want to do, isolate one room and have that circuit backed up with banked battery power and have the current being a lot cleaner than the grid juice, IS a doable project, and really isn't that hard. Frankly, I am amazed more geeks aren't into doing it. You don't need the expensive solar part to have a day or two (whatever...) of decent backup power stored in a battery bank. Later on if you get the bug you can add the solar or wind power. Neat stuff in that way, highly customizable and modular. Lot of nice current tax breaks as well for homeowners.....

You mean a solar powered ice maker like this?

http://homepower.com/files/solarice.pdf

Here is a great article on one practical application of the effect: http://homepower.com/files/solarice.pdf/

This solar system seems very plausible. The PDF is here. Anhydrous ammonia is nasty, but is also sold by the railroad car as a fertilizer. I imagine there is a way to ferment urine and distill the ammonia as well.

Oops, the heat would drive it out of an absorbant. here is the link: http://homepower.com/files/solarice.pdf

This has already been dealt with in a semi-cost-effective manner:

http://www.homepower.com/files/solarice.pdf?search =solar%20ice

The article is a bit dated, so the costs are undoubtedly off, but it's got to be one of the lowest cost solutions for this particular problem.

1. cease driving an internal combustion vehicle.

Up until I had a bad accident my primary transportation was a bike.

2. shutting off power to your residence.

Not needed if you generate the power you use. Going Off the grid is being done more and more.

4. growing your own food and processing it.

Yeap, I love to garden and I like to can and otherwise preserve what I grow.

6. avoiding the use of anything that is made with plastic.

Again not needed. Plastics were originally made from plant material. Cellophane was made from the cellulose of plants. Hemp, aka marijuana and probably the most industrially versatile plant is a good plant source. On his Iron Mountain estate Henry Ford not only built an automobile using hemp for some of the material but was also powered by fuel made from hemp. Rudulph Diesel designed his diesel engine to run on most any oil made from plants. Both alcohol and biodiesel are carbon neutral and both can be made from hemp. Actually the reason hemp was made "illegal" via the Marijuana Tax Act of 1937 was because it posed a serious threat to some rich and powerful people. When congress was "debating" the act Dr James Woodward who was both a doctor and an attorney testified on behalf of the AMA. He said all of the testimony in support of the act was nothing more than tabloid sensationalism and that it could potentionally be a powerful medicine. During WWII hemp was so important the US government made the movie Hemp for Victory in 1942 in an effort to get farmers to grow it.

Wouldn't it be smarter to cover the buildings with solar panels, use that to power half the building and cut down of the amount of smog created by the power plants instead? Your car puts out NOTHING compared to a 250Mw coal plant.

Actually from what I read, I think one place might of been in HomePower mag and/or Solar Today mag , was that vehicles are the single biggest contributers to manmade greenhouse gases. A simple remedy for this though is Biodiesel . Without modification diesel engines can run on biodiesel. Actually Rudolph Diesel the designer of the diesel engine designed it to run on most any vegetable oil. And because the plants used to make the oil soak up carbon dioxide they are carbon neutral. It's not so much how much one vehicle puts out as it is the total of all vehicles.

However more building should include solar power in their design, active and passive. One way as you've stated is pv panels. Another way is a thin film that's being developed that can be applied to windows and the sides of building to generate solar power. Another method of power generation are wind genies, wind generators.

I think that you are way behind the times on this. Financial payback for solar panel installations is on order of 15-25 years. Energy payback is on order of 3-5 years. See here for various studies.

Setup one of these instead.
Midnight Special

Homepower

Most solar water systems just feed into a standard water heater and use that to "top up" when needed, the on-demand-heater is just a bit more efficient to use.

Probably, to prevent overheating and dangerously hot water in the sunnier times of the year, one should install a cold-water-mixing valve to make certain that the hot water delivered by the system never gets scalding.

See Home Power Magazine for lots of this info - free download of the latest issue in PDF - a great mag.

See also Dilbert's Ultimate Home by Scott Adams for lots of cool home design decisions for the inner geek.

Solar power, wind genies, and alternative sources of power aren't cheap up front but over the long term they are cheaper. Depending on the system configuration a system can pay for itself in 7 years, thereafter power is "free". Some good websites are:

• Home Power
• Solar Today
• CREST

I know it would be prohibitively expensive, but you can live off the grid. Go solar, or wind maybe (or maybe you live in an apt. complex, in which case you can move). Sure you might have to give up A/C and some other things, but you do have a choice these days. The co-op can price itself out of the market. Check out http://www.homepower.com/ I believe that the gist of your statement is correct, but you do have alternitives, i.e. the government isn't preventing you from not using the Co-op.

Subscribe to Home Power

This is the best idea in the list. Another good mag to subscribe to is "Solar Today".

• "Home Power"
• "Solar Today"

  Falcon

By the way, if it really takes an individual three months to research the purchase of photovoltaics, you'd be doing everyone a service if you shared that research concisely so that the rest of us can spend 5 minutes getting caught up.

Here's two good websites you can find out more, Home Power and Solar Today

Try this:

Solar Electric Systems - Perhaps what the home-scale renewable energy (RE) world needs most are ways to introduce people to RE technologies and the gizmos that make it possible. After all, even the best ideas aren't embraced until they are explained in simple terms. So whether you are the rookie who wants to understand how solar-electric systems work, or that better describes your spouse, friend, or prospective customer, this article explains the guts and bolts of the three most common options... Falcon

By the way, if it really takes an individual three months to research the purchase of photovoltaics, you'd be doing everyone a service if you shared that research concisely so that the rest of us can spend 5 minutes getting caught up.

Here's two good websites you can find out more, Home Power and Solar Today

Try this:

Solar Electric Systems - Perhaps what the home-scale renewable energy (RE) world needs most are ways to introduce people to RE technologies and the gizmos that make it possible. After all, even the best ideas aren't embraced until they are explained in simple terms. So whether you are the rookie who wants to understand how solar-electric systems work, or that better describes your spouse, friend, or prospective customer, this article explains the guts and bolts of the three most common options... Falcon

I wonder what % of U.S. land area is rooftops & other available space.

Roofs are designed to perform certain functions, and those functions do not include the supporting of solar PV panels. When you put solar panels on unmodified roofs, generally at least the roof ends up destroyed if the whole building does not collapse. If, OTOH, roofs are modified such that they will support solar panels without being destroyed, many persons will die installing, repairing and cleaning those solar panels. This is because when people do work on roofs, they tend to fall off. These aspects of rooftop solar are pointed out on the premier solar-activist site http://homepower.com/.

- if the efficiency is high enough, you can generate a significant portion of U.S. electrical demand with solar.

Efficiency has nothing directly to do with economy, and regarding solar you can hear this straight from the horse's mouth at http://homepower.com/. If the efficiency is high enough, you might have something that excites people who know nothing about economics.

"Made" seems to be the more appropriate word, IMHO.

So, what power source can we have to extract pure H2 from other materials? Well, we can have, for example, solar power.

Greetings from Wisconsin, where the development of solar power awaits only the introduction of sunlight.

Seriously: solar power is very diffuse, and the efficiencies of existing commercial solar cells are pathetic.

Now Try making oil from wood with your chemistry kit.

OK. I would use pyrolysis to convert the wood to water gas (carbon monoxide + hydrogen), a copper catalyst to convert the water gas to methanol, and the Mobil zeolite process to convert methanol to gasoline (MTG).

It's much easier, though, to convert cars to run on alcohol -- especially since most car engines are now fuel-injected and computer-controlled.

So, is hydrogen economy all that far-fetched? No, it isn't!

Yes, it is! Tell me how we're going to store hydrogen -- safely and efficiently -- in our cars. Tell me how we're going to adapt our natural gas pipelines to carry hydrogen (or tell me who will pay for new pipelines). Tell me how to make a low-temperature fuel cell that does not require expensive precious metal catalysts. Tell me where the electricity for electrolysis is going to come from.

What are you, 14 years old? You can't replace the energy economy of an entire country with promises of "Oh, we'll figure it out LATER"

Here's a GREAT resource when it comes to "hands on" (i.e. Real World experience) solar installations.

Home Power Magazine

I've been a reader since issue #15 or so.

Second, and far more fundamental, *it takes far more energy to make a solar cell than it can ever possibly collect*.

While this rumor has been circulating for a number of years, it is not even remotely true. Depending on what PV technology is used and specifics of geography and geometry, it takes anywhere from 6 months to about 8 years for a solar panel to produce the energy required to make it. This is very well established. The panels themselves have expected lifetimes of 20-30 years.

The cell degrades before it ever breaks even.

Not only does the cell not degrade before it produces the energy required to make it, it lasts so long that its lifetime is essentially unknown. Other materials in the PV module degrade, but as I said, expected module lifetimes are 20-30 years; in fact, manufacturer warranties are generally in the 20-25 year range.

As quoted in Home Power Magazine

Some skeptics of solar energy claim that it takes more energy to make a photovoltaic module (PV) than it can ever produce in its lifetime. The truth is that PVs typically recoup their embodied energy in two to four years. According to an article published by the National Renewable Energy Laboratory (NREL), today's single and multicrystalline modules have an energy payback of about four years, and thin-film modules about two years. Most PV modules in the field are made from hyper-pure crystalline silicon. Purifying and crystallizing the silicon consumes the most energy in making these PVs. Thin-film PVs are made from considerably less semiconductor material, and therefore have less embodied energy in them. Most of the energy consumed is in the thin-film surface. The aluminum frame on any PV accounts for about six months of its payback time. Solar energy is an amazing technology considering that PVs go on to produce clean, pollution-free energy for at least 25 to 30 years after they have achieved payback.

For more information on energy payback, see the National Renewable Energy Laboratory's Web site (www.nrel.gov) and Karl Knapp & Theresa Jester's article titled "PV Payback"in HP80. --Eric Grisen eric.grisen@homepower.com

Also, concerns about lifetime and hail resistance are red herrings. Most panels are warranted for full rated output for at least 20 years and most have performed well beyond those timeframes. Also all panels are UL tested to meet UL hail resistance specifications (which I believe covers hail up to 2" in diameter).

Finally, no one bitches when a gas-fired generator fails to recoup its energy cost of manufacture--it requires billions of additional therms of natural gas over its operating lifetime to produce electricty and never pays back its manufacturing energy cost. It is disingenuous to ask that only of solar (and odd since solar can actually do it!

It can get a bit more complicated in that investing money in a technology that will decrease your future costs, is not exactly equivalent to investing money that will provide future income. Future savings are sort of like tax free income in that if you save a dollar in the future you will be a dollar richer, whereas if you earn a dollar in the future you will need to pay taxes on that dollar, which can amount to a significant fraction of that profit.

Business which can deduct some of these expenses from their income of course have a different calculation to make.

Home Power magazine had a fairly good article on this type of thing a few months back (or maybe last year?) where the author concluded that investing in compact flourescents was a better return than the stock market, while LEDs were much less of a good investment. Similar articles in the past have shown that the really best investment one could make with a few thousand dollars would be to install a solar hot water system to supliment whatever hot water system you currently have - with returns on investment of 15-30% all tax free... but I digress.

Here are some links on how the grid and customer transformers work.

You can use your existing power transformer so long as you don't exceed its power rating. Here is one utilities regulations.

And of course this hinders centralized control - if a power line needs to be worked on, how do you guarantee that no current is flowing in it?

convert the pole transformers to be dual and rig it so that if you generate excess power, your metering runs backwards

slightest mismanagement can cause blackouts and other system failures

Look. I'm not interested in a argument for its sake. Every time you pull some new reason out of the air that solar can't work I've proved you wrong and uninformed. If you want to learn more, or have informed opinions you want to share, then fine - but I am starting to feel this is going nowhere. (have you learned anything about solar in this process?)

To add to the AC's rebuttles, wind turbines kill a tiny, tiny fraction of the birds that are killed by cars and building windows. I love birds, but it's really not an issue, particularly with designs that account for some of the bird-killing problem (such as perching on the poles).

The Stone Age didn't end because we ran out of stone.

The Stone Age ended because mud huts and dung fires suck. As soon as alternatives became viable, people changed their lifestyles.

Dung fires are still used in places like India where the alternatives are simply more expensive.

The cost to me of a block of stone the size and shape of a cinderblock, don't forget the cost of handling something that heavy, makes stone far more expensive than cinderblocks for building.

That's why cinderblocks were developed, that's why they're used. They're cheap, compared to the alternatives. Stone remains, and is used when and where desired by people willing to pay for it. Just like sailboats.

I suggest you visit Home Power Magazine for a dirt level examination of the alternatives available.

Home Power isn't about pie-in-the-sky schemes, it's about real working alternative energy. Solar, wind, micro-hydro (my favorite), hydrogen, etc.

They have an unfortunate bias against clean, efficient nuclear power however. Oh well, no one is perfect.

Bob-

The article below shows a total energy payback in 2 to 3 years.

Homepower.com article

Now how about giving the source for the original, false claim.

Not exactly what you are looking for, but check out Home power magazine. Many things that a good hacker can adapt. They are most US based, so they won't cover some UK issues. (US is 60 hz)

Just watch the politics, there are very many publications more extreme on the "left". Interesting in other words, but don't believe everything they write.

You start by building a 50 to 100 foot tower on top of your home so that the turbine will be high enough to be in wind flow without blockage from nearby obstacles (i.e., trees and other houses).

Research all about windpower here http://www.windpower.org/en/core.htm as it seems to me to be the bible of wind power.

Then, integrate the power that the turbine generates into your homes power grid. This is a good resource: http://www.homepower.com/

An article that caught my eye in Popular Science pointed to these folks http://windausenergy.com/ who are making a vertical turbine, a technology which has been around for quite some time but they say that with recent break thrus in material it actually makes it practical to use.

Your wind resource depends a lot on where you are. Roofs of buildings tend to be very sheltered, and not quite the most efficient place to put a wind turbine. Solar -- in both its photovoltaic and hot-water-heating modes -- is probably a better bet for most domestic roof installations.

If you want to find out more about this, I can't recommend Home Power magazine highly enough. There's also a good crowd on energy nerds who hang out at Talk Energy who might be able to help.