PV Gap

Edith Said:

How much would it cost to run a house on solar power?

We Answered:

There are several websites that have solar power calculators that will give an estimate of the size and cost of system you need. www.findsolar.com is one that comes to mind. Just do a search for solar power estimate or solar calculator.

Monica Said:

What do I need to supplement the power in my house with 20 Watts of solar?

We Answered:

20 Watts is just too little power to do much. Using it to trickle-charge a pair of deep-cycle batteries, then using them with an inverter to run a laptop or one lamp after dark is an idea.

To sell back to the grid, you need more than 1000 watts to get anywhere. Sunny-boy is a brand of inverter that has been used with bp solar products.

Conversion of all heating loads (water heater, dryer, furnace) to gas would be a step in the right direction. With enough solar panels, a good inverter and batteries, you can run modest lighting and intermittent loads without drawing much from the grid

In my rural area, storms sack the power every month or more in the summer. The average outage is 2+hours. I use one deep cycle battery with an 800 W (continuous) inverter. It allows operation of my laptop, home-theatre and a single lamp until power comes back. A 20 W panel would be great to re-charge the battery (I swap it with the one in my truck).

Monica Said:

How hard is it to make your house solar powered?

We Answered:

For about $10K you can put a 1 kWh parts only system on your home for grid tie only. This would hook to your home in the breaker box and would be powering any part of your home. It is not enough to run all of your home but it don't matter. The solar electric system will be feeding the 1 kWh back into the grid which brings down your electric bill. You can get a system as big as you want and can over produce in which case would be powering your whole home and over feeding back to the grid.

I have my solar electric system setup as an off grid system which I use as a battery backup. If the electric grid goes down it will auto switch to the battery bank which is powered by the solar array. If I want to go solar only I just turn off the main breaker and the system thinks the grid went down and switchs.

You can get grid tie with battery backup if you like depends on your needs or wants.

Take your last 12 months electric bill and total all the kWh used and divide it by 365 to get your avg daily usage. Then get your peak sun hours from this web page.

http://www.oynot.com/solar-insolation-ma…

Divide your daily usage by the peak sun hours which will give the system size in solar modules you need. Then go to this page and pick a system that fits your needs.

http://store.oynot.com/gts-grid-tie-syst…

Or this page if you want one with battery backup.

http://store.oynot.com/gtb-grid-tie-back…

There is a little more to it then this, but will give you a very good idea of the cost invloved and how large of a system you will require.