How effective is solar power?

Filed under: Self Reliance |

solar power home
Image by UNDP in Europe and Central Asia
Find out more about energy efficiency in Armenia

Photo courtesy of UNDP in Armenia

Question by anthroguy101: How effective is solar power?
I am very concerned about global warming, and when I grow up (I’m only fourteen) I plan on using solar power to power my home (and I hope that when I grow up it’s customary). How efficient is solar power? How many square feet would it take to power a 2,000 square foot home? How much would it cost?

Add your own answer in the comments!

Have something to add? Please consider leaving a comment, or if you want to stay updated you can subscribe to the RSS feed to have future articles delivered to your feed reader.

7 Responses to How effective is solar power?

  1. Try I’m thinking it would be VERY efficient. It’s used to light alot of our fishing piers here in the south, where we tend to get alot of sunshine.

    April 24, 2014 at 9:30 pm

  2. Comment to “Ed” added…

    There are two main types of solar power. One produces electricity, the other produces heat.
    The electrical type are called “photovoltaics”, the heat type are “thermal”.
    Photovoltaics are not presently very efficient, converting less than 15% of the suns energy to electricity, but by the time you build, they should be better, and cheaper. Thermal solar is much more efficient, especially if you use it to heat your water, because the system runs all year. Home heating is not as good, because winter is not a good time to collect solar. When you design your house, you can take advantage of “passive” solar, which is basically putting a lot of good windows on the south side (or north side if you are south of the equator!) and letting the winter sun shine in. These windows need to be very good, or have an insulator to cover them at night and cloudy days or they will gain energy all day, only to lose all of it at night.

    As far as your house goes, it’s not so much a matter of how big it is, as how well insulated it is. If you “super insulate” it, you will need very very little heating or cooling energy.
    The other cost you will have is for things like computers, refrigerators, TVs, sound systems, lights, fans, cooking equipment and water heating. By picking the most efficient, you can reduce the size of the photovoltaic system you would need, and using solar water heating will handle 50% of the yearly amount with present technology for about $ 3500. A photovoltaic system to handle all your electrical needs would be quite expensive now, in the $ 10,000 to $ 20,000 range, but that cost will continue to fall, and by the time you build it should be closer to $ 5000.

    Hey Ed….I don’t know when you bought your system, or what other costs were associated with it…but 6KW systems don’t cost 40K anymore…this from Solar Today “A 25-year warranty accompanies the Sharp panels. In 2003, we paid $ 18,000, which included the eight batteries, two inverters, hardware, 6,000 watts of solar panels and labor.”….and King solar sells a “whole house” package for $ 11,000… but they don’t say how big it is. The average home in California uses about 7000 KW per month…so to get that much is going to be more expensive. Our young friend here is thinking ahead. If a house is located right and designed well, then the most efficient appliances and lighting is selected, it would be easy to live well on half that 7000KW.

    Good luck, and good thinking!

    April 24, 2014 at 10:00 pm

  3. Solar power stuff is contolled but the oil company patents, it will never be cost effective

    A passive system that heats water you can get some return

    April 24, 2014 at 10:58 pm

  4. I think Roadlessg is way of base on his cost estimates. My 6kW system cost close to $ 40,000, here in Martinez CA. Only by being extremely frugal, and living alone can I supply all my electrical needs. I still heat water with gas. I do agree that a photovoltaic system is the way to go.

    Do lot of studying before spending any money on a solar system.

    April 24, 2014 at 11:13 pm

  5. #1 it won`t work if you don`t have SUN. If you`re in a region where you have varying amounts of cloud cover your effectiveness may be deminished. Also consider exsisting trees. They will also factor into the equation. SNOW. A blanket of this stuff during the night will shut you down come morning. An upside question you may want to ask, will your power company buy your surplus if available?

    william v
    April 24, 2014 at 11:42 pm

  6. A quick down and dirty way to get some numbers is to get your last 12 electric bills. total the kWh and divide it by 12. Divide that by 30. Divide that by the peak sun hours a day. For the USA could be anywhere from 3 hours a day to 5 hours a day. That will be some where near the size of a system you will need in kWh. Mutiply that by about 8 dollars.

    So if you have 575 kWh usage per month divided by 30 days gives you 19 kWh per day. Divide by 4 sun hours per day. You will need a 4.79 kWh system. So now 4,790 watts times 8 dollars a watt is $ 38,320 USD.

    That is an idea of how to find the rough numbers. Now if you do all the work your self you could save a dollar or even two by not paying someone to do it for you.

    Here is a do it your self site if you want to read up a little. The site is not written with the reader having a PHD in mind. It for the everyday people.

    Don K
    April 24, 2014 at 11:51 pm

  7. If you are interested in solar power, I suggest looking up the Solar Decathlon. The Solar Decathlon is a college competition in which twenty teams are building solar powered houses. It is held every two years, the next being in September of 2007. It is held on the Mall in Washington D.C. I’m on the Penn State Design Team and I promise you if this is something that interests you, it will knock your socks off.

    April 25, 2014 at 12:45 am

Leave a Reply

Your email address will not be published. Required fields are marked *