Are Hybrid Solar/Grid Houses Practical? 54
Controlio asks: "With the continuing power crisis and the announcement of major power rate hikes, I figure now is an excellent time to pose this question. Instead of pay these inflated prices for power, I'd like to sink my money into a long-term solution. Cutting myself off from the power grid isn't practical, as I use too much power periodically to be 'solar-only'. But how practical is adding solar for either power redundancy (in case of a blackout) or as supplemental power? Redundancy would be nice, but being supplemental would involve using solar power as my primary power when it's available (and I hear tell that you CAN have negative electric bills if you produce more than you use). Do the costs/advantages for either provide enough incentive to be worth investing in? How would one go about creating a hybrid house? And finally, of course, which is cheaper? Investing in expensive solar paneling, or paying the outrageous charges the power company wants?"
Re:Sort of... (Score:1)
I suppose that the drillers ignore the natural gas that is pumped out of the well that also pumps oil.
Conservation is not the solution. The population is growing faster than any savings from conservation.
They do ignore the natural gas (Score:2)
Solar Panels or Solar Furnace? (Score:3)
Another way to reduce power bills would be to use solar power to "preheat" water by a few degrees and then heating it up conventionally to the required temperature.
If it's electricity you're after, a "solar furnace" might be better. You get a nice parabolic mirror and pass cold water across the focus. The focused light heats up the water and makes steam which can be used to drive a turbine, driving a generator. You can also use the heat directly to melt metals. (Sunlight is at a temperature of 6500K)
Re:Solar shingles (Score:1)
http://www.ovonic.com/unitedsolar/roof.html
so you can subtract the cost of reroofing your
house from the total cost of solar. That and here
in california the state will pay 50% to install a solar system!
Sunslates (with link) (Score:3)
HTTP://WWW.ATLANTISENERGY.COM/ATL/default.asp
The actual cost of all energy sources (Score:3)
According to this article [crest.org], the actual cost of gasoline once the tax breaks the oil companies are given are added back in is around $15.14 per gallon. Ouch.
Nearly every source of energy suffers loss in production like this. If you're going to apply that standard to solar, apply it to other sources as well.
Keep the location in mind (Score:1)
AC/DC (Score:1)
Small Lesson in Market Economics/Energy (Score:2)
It's a waste byproduct if you can't sell it. Or get it to market.
That's the short version. The longer version is that natural gas in North America comes primarily from Canada, and from the United states. Very little of it is ever shipped by boat from one country to another. Natural gas is expensive to ship, it requires cryogenic/high pressure storage, special ships, and on and on (but they're trying to increase safety and lower expense all the time). The cost of shipping natural gas is quite low by pipeline, and higher for petroleum and oil because you must heat the oil so that it's thin enough to be pumpable. The lowest grade crude oil is thicker than peanut butter.
If all of the Alaska Wildlife Refuge were tapped and drilled, it would produce a maximum of something like 600,000 barrels of oil per day, starting in about 8-10 years. The current global oil production is around 75,000,000 barrels per day, with the U.S. sucking about 15-20,000,000 of that down. For a good reference to read on this topic, see here [epinet.org]. Overall, because the U.S. hasn't modernized at the same pace as Europe, we consume roughly 25% more energy to perform the same tasks (both at home and in industry). If we had modernized over the past years at the same rate Europe did, we would currently have a 10-20% energy surplus, compared to what we consume right now. And we wouldn't have to build a single power line, power plant, or drill a single well to get it. Energy companies would have to invest no new money in risky exploration and development. They would earn more, and their stockholders would achieve higher returns. There is no long term downside to conservation. In the short term, energy sales goes down. Lower sales drives process efficiences, and the companies learn to make more money on less effort.
Back to natural gas. Because of the specialized equipment required in shipping natural gas, and the expense of moving it long distances, almost no one will buy it who's not living on that continent. That means that NG in Saudi Arabia doesn't get sold to the U.S. If there is no market, it is not transported. If it is not transported or sold, then there is no reason to store it locally, as that is another expense. Thus it is burned onsite as a waste product.
It's a fact of doing any task. What you consider waste product might not be considered waste if someone else had a use for it. Very few people these days have use for the bones and hides of the animals they consume (or even see the bones and hides).
The short truth is that it will take years, even at a frantic war-time pace, to develop the oil that's under the Alaska's wildlife refuges. There's the surveying, getting equipment there, infrastructure, finding laborers, moving the prodcut -- it all takes time.
Conservation, on the other hand, can have an effect right now. Rolling blackouts are a form of forced conservation. Much less drastic measures are tax breaks/incentives, and new taxes on consumption to affect behaviour. While that sounds evil, it's already done quite a bit. Taxes on cigarettes, alcohol, gasoline, furs and diamonds, expensive cars, SUV's (low miles-per-gallon tax), airport gate taxes.... The list goes on. If President Bush had made an impassioned plea to the people of California to conserve, and to set their air conditioning three degrees warmer, and so on, there would have been an overnight change. America conserved all it could during World War II, because it needed to. It needs to again, and the enemy is ourselves.
Sort of... (Score:5)
If it's a new house, meaning you haven't broken ground yet and you're still talking to the architect, then you can make the energy savings work. If it's an existing house, then there's quickly diminishing returns.
The Canadians experimented years ago with super-insulated houses located up on Hudson Bay. When I say superinsulated, I mean four-foot thick insulated walls with foot-thick panels that closed over windows at night. It wound up being that the body heat from the occupants almost heated the house. If you cooked, even in the dead of winter, you had to open a window. Some of the solar heating panels were disconnected because it actually overheated the house. If you insulated a Florida or Arizona house that much, you could keep it nice and cold inside. (Insulation doesn't just keep heat in.)
If it's solar power you want, well, that kinda works. You can live off it, but it takes a lifestyle change, and some rewiring. No distributed.net cracking for you, and you'll need to get rid of all those appliances (microwave, stove, VCR) that use power when they're not on (those little clocks and indicator lights add up). The Chicago Tribune ran an article a few months ago about apartment dwellers, in urban Chicago, who had gone solar. It can be done, it costs money, and a lifestyle change is mandatory. No blow-drying your hair, no clothes dryer, no electric oven.
Wind works pretty well, depending upon where you live, and depending upon zoning laws (neighbors may not want one looming over everything). There's some concern that wind power kills birds, but since they tend to place those flailing blades in prime bird habitat (open grassy fields), then it may not be a causal relationship. All the old windmills and wind-powered water pumps don't kill birds, so someone needs to get a big grant and do more research. It might be habitat/proximity, and it might be blade design. Maybe noisier blades would help.
What alternative energy for an existing home does do is cut down peak use, and perhaps spin your meter backwards sometimes. There's tax breaks for alternative energy sources, but basically be prepared to write the whole expense of installation off, and consider it paying off Mom Nature's bills. Figure $10-20k to get anything significant going. You'll need a big bank of batteries to store that peak power to consume during off times (like nighttime), or just spin the meter backwards and sell it to the local utility.
If you're lucky enough to have a running stream nearby, there are companies that sell mini-hydro devices. It's not a small dam, but just a small turbine that a head of water spins.
Try http://www.homepower.com [homepower.com] as a great starting point.
Contrary to Bush's pathetic energy plan, the real solution is (in order), Lifestyle change, convervation, and consumption limiters (insulation, efficiency changes [better appliances]). Drilling for Alaskan oil won't create one watt of power for California since California doesn't have any commerical power plants that use Petrol as a power source. They may augment power generation with these things [cat.com], but it's not really what you build a power plant from.
Here is someone who's done it (Score:3)
This place has been featured on the History Channel and HGTV. Okay, it's in Maine. Maine is a long way from California. In this case, heating via solar is a goal (but not exclusively), just perhaps more so than in a California home application.
I'd wonder, carefully considering de-regulation, if you can choose which power company to sell your surplus to...? It might be something to consider, as I have seen advertising for power generators in California with different goals (environmentally friendly & socially conscious vs. low cost & raping the land, etc...)
He speaks directly to California residents in several places, and has a point that I envy.
(No such luck in my home state, dammit.)
(Final "grain-of-salt" note -- I don't agree with some of the cost numbers he quotes for non-solar houses. $400 worth of heating oil used in just 28 days??? They must have been heating all of southern Maine! Perhaps they had a 500 gallon tank topped off, but I can easily make that much heating oil last for 6 months... and that includes hot water, too. Yes, my place is smaller, but I have horribly leaky windows, and not-that-great insulation... I still don't use that much oil.)
I would like to do this (Score:2)
One of my questions is about solar panel maintenance. Here in Kansas we get hail storms. They happen every year. Sometimes it misses an area or two and sometimes it totals vehicles and crops. Will that kill solar panels. Is there a way to protect them? Maybe a hard screen or wire screen 3-4 inches above the panels would work. Another question is about winter. Will hard freezes affect the panels at all? Would motor oil be better used in a case like that or water with anti-freeze (since it will be thinner than cold oil). What about battery life and maintenance? Will that be a big hassle? I'd love to find a good resource that can set some of these concerns to rest. It would be a really viable source energy-savings I think. A windmill isn't out of the question either. Any thought or past experience anyone care share is greatly appreciated.
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Thanks (Score:2)
The reason that guy used motor oil was because of its thermal capabilities. It holds heat really well and he had plenty of it to spare. Freezing isn't a worry either, although you can't let it get too cold or your circulation pump will hate you. :) Water and anti-freeze would work too but I would think that your pipes would eventually gum up.
I think a wire screen could protect a solar panel. Let's say 3/4" by 3/4" screen primed and painted black, stretched over the surface of the panel about 4" away from the glass and supported with a square tubing framework. I think that would protect it from most hail. Baseball or softball sized hail might still break through. Any hail smaller than that probably won't hurt the panel. It's an interesting thought. I think it's doable. I'm going to have to dig around for details on how to convert and store the electricty those cells pump out. I should have finished that dual computer/electrical engineering major. That would have helped. :)
The winds depend on the season and the year. I remember one winter way back in HS when we had a bit of a dust bowl. The ground was super dry. We had just had about 16" of snow and everything but the snow was a dry as dirt. The snow/dirt off of the fields started blowing. Visibility was null. It sucked. In late May, towards the last day of school with 90 degree weather there was still snow in the deepest ditches. The dirt insulated the snow so well that it didn't melt. If you cut a core out of it with a knife, you'd find dirty snow under the top layer of dirt. How much wind do we have to have a productive windmill?
Thanks again for the reply.
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Real Goods is an excellent source of knowledge (Score:2)
They also host educational sessions but I have no firsthand experience with them.
Re:Here is someone who's done it (Score:2)
Doesn't seem unreasonable to me...I can go through $200 worth of oil a month during the coldest months in Baltimore. (50 year old, three bedroom house, maybe 1800 square feet, moderate insulation (and that's upgraded...it was piss poor when I moved in, but some new windows and some foam blown into the walls have helped a lot.))
I could imagine that between regional price differences and a colder climate, a larger house in Maine could pay twice that much.
Tom Swiss | the infamous tms | http://www.infamous.net/
Re:The short answer is... (Score:2)
No, they don't. They pay back the energy required for manufacture in about two years.
Modern PV panels are rated for about a twenty year useful lifespan.
Doesn't even have to be in the middle of nowhere...the break-even point between running copper and a modest PV setup is, IIRC, on the order of 100 feet.Tom Swiss | the infamous tms | http://www.infamous.net/
Re:Small observation (Score:2)
You might also consider a tankless water heater. Gas ones have been around for a long time and are, I understand, common in Europe; electric ones have recently come on the market.
There's a larger upfront cost, but they last a very long time and are quite efficient. (These guys [tankless-w...heater.com] claim a 50% energy savings.)
With a tankless heater, you can only draw n gallons per minute, but for as long as you desire; whereas a tank heater lets you draw pretty much unlimted hot water per minute - until you run out. I'm seriously considering junking my tank heater for a tankless one just so I never have to wait for hot water after someone else takes a shower.
Tom Swiss | the infamous tms | http://www.infamous.net/
Re:The Independant Home (Score:1)
Well, I did an Amazon search on "independent home" (with "ent", not "ant") and did turn up a couple of books that looked correct. Try the search that way--is the book you're talking about in there?
Re:The short answer is... (Score:1)
Energy Payback Time on PV cells is well within the lifetime of the cell. Amorphous Silicon Cells payback in about a year, Normal high-temperature crstal melted cells take 4 years. The high-yield single crystal cells might not be able to pay themselves back, I'm not entirely sure. I'm not exactly a PV engineer or anything...
The current high-yield, ultra-expensive cells get 23% conversion, other cheaper ones get between 12% and 18%
And the citation...
http://www.atip.or.jp/ATIP/public/atip.reports.97
Section 3 in there has most of the info I paraphrased here.
~Anguirel (lit. Living Star-Iron)
"Veni; Vidi; Vi C++"
Re:Keep the location in mind (Score:1)
I know Japan has high energy costs, but most regions also have frequent cloud-cover. If you live in Sunny Southern Cal, there's a good chance that solar panels would be in almost constant use. I didn't say my data was flawless, but at least I made mention of where my numbers came from. If you live in Seattle or the Bay Area it probably doesn't make sense to use Solar Panels. But hopefully the questioner already realizes this...
~Anguirel (lit. Living Star-Iron)
"Veni; Vidi; Vi C++"
Re:The short answer is... (Score:1)
Yeah, that's right, because as we all know R&D nevers pays off and technology never gets any better, so PVs will never beat good old-fashioned grid power, so just forget about it, OK? Just go back to sleep, America, everything's fine... those fruity renewable power enthusiasts won't make any progress here if we have anything to say about it...
Re:Sort of... (Score:1)
Seriously, if you have a population of $num people, and each person is consuming $quan amount of energy, then the total consumption is of course going to be $num * $quan. If each individual can reduce their consumption, even marginally, then the net result -- $num * ($quan - $conserv) -- can be pretty significant on the aggregate. Certainly cheaper than producing lots more power plants.
I'm willing to accept that we may need more plants, but it would be a lot less expensive for everybosdy if, say, everyone stopped driving those stupid Suburban Ussault Vehicles. The reality is that any solution is going to be a big, expensive project for the country to undertake, and anything that helps control the size & burden of that project would be much welcomed.
The short answer is... (Score:2)
From an economic standpoint, if the power grid is available, PVs will never beat the grid. If your home is extremely isolated, then PVs start making more sense, because it can be very expensive to run power out to the middle of nowhere.
Re:The short answer is... (Score:2)
But even in Hawaii, which traditionally has some of the highest electricy rates in the US, this report http://www.hawaii.gov/dbedt/ert/pv_hi.html [hawaii.gov] states advantages and disadvantages- notably:
1. Photovoltaic-produced electricity is presently more expensive than power supplied by utilities.
...
4. Batteries need periodic maintenance and replacement.
5. Some of the materials used in the manufacturing of PV panels are toxic.
Most of the references I found when googling the topic were positive when they were trying to sell you PVs, and neutral otherwise- look at the sources of the articles- Siemens has a great interest in you buying their PVs. Really, it gets into the classic case of shifting the pollution to a lower-rent district- not really providing a global solution.
With PVs, not every place is the same- KWh/year of sunlight at installation location, PV conversion efficiency, energy costs, area available all have an effect on the final cost. No payback time estimate is valid unless this data is included. I'll maintain my original proposition- PVs don't make sense if you're trying to save money on energy for the average home.
Re:Small observation (Score:2)
Small observation (Score:3)
By parents have two solar panels on their house (Phoenix). These panels power their water heater for them. The water heater is not on a schedule - the water is always being heated. Their house is about 2,000 square feet. The entire house has vaulted ceilings.
My house has no solar panels and is about 1,500 square feet. I have only two rooms that are vaulted (living room and master bedroom). I'm also in Phoenix.
Our electricity bills are the exact same.
What they save in heating the water with solar power allows them to cool 500+ more square feet. I estimate that the water heater represents about 1/4 to a 1/3 of my electricity bill.
Re:The short answer is... (Score:2)
Re:Small Lesson in Market Economics/Energy (Score:1)
Furthermore, there are no plans for the new drilling in Alaska to supply natural gas--the cost of a pipeline for it would be prohibitively expensive for the amount it might supply. California does not use oil to make electricity; it's primarily a natural gas state. Therefore, new oil drilling in Alaska does nothing to help with California's electricity woes--oil is much more valuable to be refined and sold as oil than converted to electricity.
Re:Solar Panels or Solar Furnace? (Score:1)
That conversion rate is actually quite impressive. The sun sends lots of energy our way (peak about 1.1 kW/m^2), and converting 10% of that into electricity is quite impressive.
The real efficiency problem is one of cost--look at the $/W numbers of solar photovoltaic panels and solar/battery (batteries are extremely expensive) systems, and see how they compare to conventional sources or wind. The places where photovoltaics are efficient are remote places where electricity is unavailable. They're much cheaper than stringing new electric lines to the middle of nowhere.
A solar-powered turbine can be cheaper, but requires much more maintenance and is not something that scales down to individual household use cheaply.
If you're after reliable power, get a generator and UPS. If you want to help the environment, stick to cheaper energy sources (wind, water?) and donate the money you would have spent on solar on organizations which fund research on environmental issues and alternative power.
Re:Cringley has the answer - Batteries (Score:1)
1. The electricity would have to be converted from AC to DC (to be stored in the battery) then converted from DC to AC (since that?s what your appliances use).
2. Batteries (in the quantity needed) aren't cheap.
3. Batteries are amazingly bad for the environment.
Re:Small observation (Score:1)
Re:Small observation (Score:4)
There is a really good web page at http://hit.lbl.gov/ [lbl.gov] with more information about reducing your utility bills.
Here's what I think. (Score:1)
It's a case of making energy and materials plentiful at low cost.
The more cheap energy you can get to convert to high value stuff, the better your economy is.
Spread the cheap energy around and boom, tons of things come alive that you'll never see anywhere else - lots of silly little toys etc.
It's just like comparing the tropical rainforest, a temperate forest, and the Antartic and Artic. I'm sure polar bears and other Artic creatures are a lot more efficient than some random creature in the tropics. But you sure don't have that many creatures in the Arctic, and it's harsh.
Plentiful energy makes a big difference, even if a lot of it is "wasted" on creatures/businesses which in lower energy situations will just die out quickly.
It's probably why the US economy was and is doing better than the EU.
Someone, somewhere at the top in the US seems to know that, which can explain the US actions regarding the Middle East, global warming and so on.
economy != economical.
Cheerio,
Link.
Re:The short answer is... (Score:1)
Good info (Score:1)
I have been planning my house for the last few years and I can tell you that you have not EVEN scratched the surface yet. You can build houses out of straw bale, hebel block, SIF's (structural insulated forms), etc. (http://www.ci.austin.tx.us/greenbuilder yes, I live in Austin,TX
For heating and cooling, I didn't see anybody mention geothermal. EXTREMELY efficient! There are all kinds of sources. (www.demarcoenergy.com,www.waterfurnace.com)
The big problem with solar power is that the batteries are so d*mned expensive. They take up about 1/2 the cost of the system. Wind power is great but there are a few more options.
I could go on and on but lack the time. Definitely check out all the options available to you and take your time.
Re:I would like to do this (Score:2)
Water holds heat much more densely (more J/degree)than most anything else, including oil. When you put a sufficient quantity of antifreeze in it this effect is diminished, but still present. Water and Water/Glycol therefore make excellent heating/cooling fluids.
If you want a really massive amount of heat-transfer, the phase-change to steam is the common way to go.
The first action is proper sealing of buildings to be extremely non-leaky. Then some people recommend a small purposeful leak on the top level. Canadians usually recommend making sure you have underpressure in your house, or else your respiration moisture will rot your insulation - no joke! The second action is increased insulation.
I definitely, absolutely, and without a doubt think that a good geothermal heat-pump system goes much farther towards your goals than any particular generation. This essentially involves some welldigging. I suppose that's the third action.
The fourth is water preheating - essentially a thinnish flat tank of water out in the sun - like on your roof. This tank reduces (pretty dramatically) the amount of power you have to put into your water to make it warm. As a bonus, it absorbs heat during the day and keeps a lot of it around at night (as long as it doesn't freeze and burst) Along this vein are other natural ways to trap heat - I once saw an indoor pool coupled with many double-pane skylights.
Only after all of these is power generation seriously likely to make a big difference, unless you're particularly lucky about wind or water where you are. Both are wonderful in some places.
The latest (Score:2)
It will cost $10K to $20K to get solar electric providing most or all or your household electricity. RealGoods.com is the best source of practical info. Lately the advancements seem to be in making "plug-and-play" on-the-grid equipment, i.e. you don't have to have an EE degree to set it up or pay a top dollar electrician to figure it out. Most states have net-metering laws which require your electric company to reduce your bill to at-most $0 (at least in Virginia) based on how much electricity you produce. There are links under doe.gov that detail your state's laws.
The low-cost intro to saving money with solar is through hot-water heating or pre-heating. Search the web or try the library - I have found books from the '40's with solar hot-water heating plans!
Also if you are building a house now there are a few simple rules that will drastically effect you heating/cooling bills such as facing the windowed side of your house south instead of towards the $%^&&^&* street.
Good luck.
Cringley has the answer - Batteries (Score:1)
Robert Cringley wrote a column the described how to solve the energy crisis. Basically, eveyone would have a battery that would store energy during the night and release energy during the peak times. I don't know if this would provide any benefit now - I believe that energy costs the same no matter what time it is sold.
Check it out:
http://www.pbs.org/cringely/pulpit/pulpit20010510. html [pbs.org]
Solar thermal electric and dish/Stirling engines (Score:1)
Some studies [crest.org] have been done using a parabolic dish or trough to drive a Stirling engine. I have investigated buying an old satellite television dish with tracking motors to track the sun. All I would have to do is paint or cover the dish with some highly reflective substance. That part is fairly cheap. I can't find the Stirling generators used in the article above. None of the Stirling engine producers seem to be selling engines to the open market.
If anyone knows where to buy a commercial solar thermal-electric Stirling system, I would like to see that posted here.
tankless heater (Score:1)
starting place (Score:2)
otherwise I would advise, that you spend some hours reading about solar power and some of the things you need to take into consideration.
As most of the above posters advised. Insulate your home. That will reduce your load, one that is done then look towards solar power as the alternitive means to power your home.
ONEPOINT
The Independant Home (Score:3)
There's a great book on doing all of this stuff called _The Independant Home_. Unfortunately, it seems to be out of print, as I can't find it at any of the major book outlets online. However, Amazon (I know, I hate their politics too, but they have a useful search engine) has a bunch of books on building renewable energy into your house. I don't know how good any of them are, but it's a place to start.
I took a class in renewable energy back in college, which is where I picked up the book I was talking about. At the time ('96) it was still hard to get a lot of "modern conveniences" like TVs bigger than 8", or non-portable stereos that are 12V friendly. And forget about appliances like dishwashers, washing machines, and clothes dryers. Now if you make your battery storage array big enough, and also include wind power for the cloudy days, then with the right inverters you should be able to run a lot of your stuff "off-grid". However as you point out, unless you are willing to make substantial lifestyle changes and invest a buttload of money up front, you are never going to reach self-suffience.
What it really comes down to is how much money and work do you want to invest in this? If you have enough land, and you do a combo system (PhotoVoltaic and Wind let's say) then you can probably generate enough power to not have to worry about rolling blackouts, at least as long as you're smart about it and don't run your oven, 6 microwaves, and clothes dryer while you are off-grid.
If you throw a hotmail.com at the end of my handle, you can drop me an email and I'll buzz you back with the publication info on that book. I have it at home in a bookcase with all my college stuff.
Re:The actual cost of all energy sources (Score:2)
Fossil mining powers itself and produces a surplus. PV doesn't - if you built a PV production plant powered by PV arrays, it couldn't even sustain itself, let alone produce arrays for me and thee to use. I can see a clear distinction there.
Unfortunately, that's bad news. Fossil is strictly limited, and all sustainable sources suck badly in the cost/production department, and also need a lot of space. I just hope we get enough nuke plants built before the oil dries up.
Solar shingles (Score:1)
Re:Sort of... (Score:2)
The cost of solar drops if you eliminate the storage batteries and use the electricity to reduce the size of the utility bill. If this $ savings is less than the interest you could get by leaving the money in the bank, leave it in the bank. Generally, it is less. Since the cost of solar keep slowly dropping, and utility costs keep going up, waiting may make good sence.
That's not how it works. (Score:2)
Gray Davis is an idiot. If he had a brain in his head, he would have pushed to make solar water heaters mandatory on all rental housing and new construction. Instead he keeps pointing fingers at the utilities. I hope the voters of California are smart enough to boot his mangy bum out of politics (I'm smart enough not to live in California).
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Re:I would like to do this (Score:2)
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Re:That's not how it works. (Score:2)
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You're welcome (Score:2)
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Re:Small Lesson in Market Economics/Energy (Score:1)
Re:Cringley has the answer - Batteries (Score:1)
Re:I would like to do this (Score:1)
Grid Interactive Inverter System (Score:1)
Need this kind of information (Score:1)