A few people do “off-grid” solar. They install batteries to store their extra sunny hour power and then use it when the Sun isn’t shining.

Off-grid is more expensive than grid-tied and generally isn’t worth the extra cost unless you live at least a quarter mile from the grid and going off grid would let you avoid connection costs.

Electricity is electricity. If it’s the right voltage and frequency (about 120 volts AC and 60 cycles (Hertz) in the US) and you’ve got enough of it you can run whatever you want to run. I’m off the grid and run a full woodworking shop in addition to all the normal household stuff with solar. During the winter I have to use a generator some days when there isn’t enough sunshine.

Determining the size of your solar system needs –

Start with figuring out your daily average electricity usage. Use your statements to find out how much you use. (And this would be a great time to think about how you might lower your use.)

Then look up your average daily solar hours. Find your place on this map – http://www.wholesalesolar.com/Information-SolarFolder/SunHoursUSMap.html

Let’s say you live in Louisiana or Nebraska which are Zone 4. You average 4.5 solar hours per day over the entire year.

Then take your average daily usage, say 30 kWh, and divide by your average solar hours. 30 kWh divided by 4.5 solar hours means you would need about 7,000 watts (7 kW) of panels to produce as much electricity as you use a year.

(Another good time to figure out ways to cut your electricity usage. The less you use, the fewer panels you need to buy.)

Want to get a post up on that, but need up to date state installation numbers. Stan, know where those are?

A 14% drop over the same time frame would have produced 2€/W.

I’m willing to bet that our rate increases. Others have already shown what is possible.

Worse, the incentives are already fading.

We can do better.