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42

Installing solar should be one of the last things you do. You should first concentrate on those things that will reduce the amount of energy you will be using. "The Green Building Advisor" has a good article on The Energy Efficiency Pyramid. I believe this article will help you make some wise decisions about where to start.


22

Payoff depends on the state you live in. NJ allows you to sell your energy credits to other companies so in NJ it is about a 3-5 year payback (which is great). Other states have similar programs or offer rebates. Check out One Block Off the Grid (http://1bog.org/) if you are interested in solar panels. They have been great at getting information about ...


12

It depends on your point of view. PV cells are a gamble from a financial POV... depending on the state you're looking at and if you finance you're looking at a 5-12 year payback. The cells are supposed to last 20-25 years, but you may need to replace some equipment after 10-12. Upsides: Energy prices will probably rise. Peak energy demand drives energy ...


9

Smaller panels are one way to go; see this article Hail Damage and your Solar Panels: If you decide to install photovoltaic modules and worry about hail damage, there are a couple of things to consider. One of the most important concerns the size of the modules. If the region you live in is subject to frequent or serious hail storms, ...


8

Very late in answering this, and my computer's wireless modem is acting up, but ill try my best from my phone. Assuming only the 30% tax rebate (i.e. not including state, local, REP, etc. incentives,) the payback on PV is roughly 15 years. The good thing about it is that as electricity gets more expensive (a long-standing trend with only one significant ...


7

Scott Adams (Yes that one), recently wrote an article,'How I (almost) saved the earth' talking about his experiences with solar cells. Ultimately he concluded they weren't worth it from a ROI perspective. We have a photovoltaic system for generating electricity. That's the most visible sign of a green home, and probably the dumbest. I expect the ...


7

You need an on-grid inverter, and you can buy them far cheaper than you can possibly build them. In any case the power company and electricity regulator won't let you implement the circuits yourself unless you're prepared to spend thousands on certification tests, including requirements to for example shutdown within a millisecond of mains loss.


6

In some places you can lease solar. They maintain all upkeep. You pay a bit extra each month but have no upfront costs. I can only post one hyperlink, but know of three companies. They are Solar City, SunRun and Sungevity. However, as mentioned by @jay, generating your own power is the last step. First you need to calculate your usage. Then reduce. Then ...


6

Good and affordable are both relative to many local factors. Your best bet is to look around you and see what fuel source is abundant. You'll also want to think about how often/long that resource is present during high power use periods as you'll need to store the power for later use which can rack up the price. There are areas of Michigan that are some of ...


6

If you're in the northern hemisphere, the lower angle of the sun in the winter is probably contributing to your low numbers. (When the sun is low in the sky it passes through more atmosphere to reach the ground.) Presumably you'll do better in the summer. Also, the tilt angle of the panels should be matched to your latitude. If your panels are mounted on ...


5

Actually your AC is much more efficient than that because it is a heat pump, not a direct conversion of electrical watts in to BTU of heat moved per hour. If you know your SEER rating, you can just divide the BTU/h by SEER to get Watts. An SEER of 10 is very common so that would mean each AC needs 800 W to move 8000 BTU per hour. ...


5

Since you have an old car battery, the cost of damaging it by overcharging isn't much ($40?) and that would only happen if it got a lot of sun over weeks. A small home solar system might have thousands of dollars of batteries, so standard practice has long been for those to always have charge controllers. For small systems the cost of a charge controller ...


4

I've been following the blog from a fellow Canadian, Dennis S., who has installed solar panels on his urban home under the Ontario microFIT program, whereby the province guarantees to buy your solar-generated electricity at a generous contract price... similar to the popular initiative from Germany. Dennis blogs at greentoronto.me. He's written about the ...


4

I looked into PV systems in San Diego a few years back. Got a quotes from 3 or 4 companies, and after rebates, the breakeven in nominal dollars was 20+ years. Total cost to zero out our electricity bill was around $23k. A few years later, there was around $6k or so of new government incentives over and above what was available before, so I went back to a ...


4

Neither choice is perfectly accurate and specific gravity is going to vary based on temperature and the quality/purity of electrolyte in the water over the life of the battery. The fundamental change to a battery over it's life is that the internal resistance of the battery increases and therefore the same level of chemical charge will end up resulting in ...


4

What you're describing is basically what you'll find in an RV. However, it's not likely to be as useful as you might wish. The "12V" in the name of a lead-acid battery is nominal. The actual voltage might vary between 10V and 15V. Most electronics can't tolerate that kind of variation. Audio components can suffer from ground loops. Even though many devices ...


4

You have fifty-six 240-watt modules. They each produce 240 watts under standard test conditions (STC). STC is defined as 1000 W/m^2 of irradiance, 25ºC temperature and AM1.5G spectrum. These conditions are rarely reached outdoors. If the temperature is higher or the irradiance is lower than STC, you'll get less power. You can usually only achieve 25ºC ...


3

I'm pretty sure you don't want to substitute that fuse. First off, the original fuse was rated for 1 A, while the new one is rated for 2 A. You'll have twice the current allowed in your system before the fuse goes. Second, the power (wattage) permitted to pass through the second fuse is 67% greater than the original fuse would allow. Grainger has an ...


3

You're referring to a differential thermostat control, which I believe is fairly standard on solar water heaters: In active systems using pumps, whenever the collector is hotter than the storage tank, the pump should be on and the system circulating. When the tank is hotter than the collector, the pump should be off. This function is ...


3

Stacking the panels on top of each other should be fine, but I would not suggest stacking all off them on top of each other as the bottom one will have to bear tremendous weight and might warp it. Try and place wooden battens (for air flow to stop moisture from being trapped and help displace weight evenly to the next panel using a soft surface) between ...


3

Another view on this.... Your cost of power has doubled so the easiest way to offset this would be to reduce your power consumption. Newer CPU's consume significantly less power than CPU's of just a couple years ago. Monitors backlit via a LED are more efficient than monitors backlit via a CFL. SSD's use less power than traditional hard drives. Laptops ...


3

My neighbour has a solar grid and one gotcha he told me is that if any of the panel is in the shade, then the whole panel produces 0 volts. He cops shadows from my house plus a house 30+ metres away. Check your prospective panels to see if they suffer this limitation and check your roof to ensure you get constant sunlight. Another gotcha (in Australia) is ...


3

There have been lots of answers with complex equations regarding ROI and speculations about cost of energy and/or solar panels going up or down. You might consider a different point-of-view. You might consider the "insurance value" of having electricity when others do not. Smithsonian Magazine recently examined the prediction of the much-maligned Club of ...


3

You can solar heat the primary loop with high temp evac tubes in principle but what happens is you mess up the control of the return temperature which is critical for the operation of the condensing boiler. Preheating the tap water is the better approach because you are heating the water before the boiler loop tops it off. This doesn't affect the existing ...


3

Photovoltaic windows are not commercially available. Most examples of this idea, including the SolarWindow to which you linked, are made of organic photovoltaic (OPV) materials. OPV is, compared to other PV technologies, in a very early stage of development. Laboratory cells still have quite low efficiency and very short lifetimes compared to more mature PV ...


3

In the US in most jurisdictions, house wiring of any sort still falls under the National Electric Code. It has a brief section on low voltage power distribution, AC or DC less than 50V nominal. Wiring must be at least 12 Ga copper or equivalent, with overcurrent protection. The system must be grounded. All work in a neat workmanlike manner. And a few other ...


3

Allot of DC devices at home run at various voltages from 22Volts down to 5Volts. So just running a 12Volt wire is impractical because you would have to regulate the voltage up or down - Just like with 110/220Volts now. That is why you cannot find a receptacle for 12 Volts. But You can use a 5Volt receptacle :) OK- But what has that got to do with ...


2

PV is great, but it's even greater when a few things come together at once. First: learn to make yourself NOT waste electricity. This will mean you don't need as large a system. Most people (at least in the US) would be STUNNED to know just how much electricity they waste in a year. You can often cut the cost of a system in half, if you make a real effort ...


2

I had 38 x 175W solar panels installed in September of 2008, amounting to a photovoltaic system of 6.8KW. My system has been "cost effective", and has already "paid for itself", but only when taking into account the rebate I received from Austin Energy, as well as the tax deduction I took in 2008. Without those two subsidies, I would still be 15-20 years ...


2

1.) Golf Cart batteries are the easiest supply for a home electric backup battery bank. 2.) Bigger is better with the solar panel array. If you're only going to be running the router (why not the modem too? Or is it combined?) you can probably get away with a cheap small solar kit from these guys : Silicon Solar They offer some great battery charger kits ...



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