question on purchasing a nonsolar house for solar

[offbeatbassist]

My wife and I are beginning to look at properties for purchase and I am curious if/what to look for when looking at houses? We are new to the ideas of getting off grid and know very little about supplemental power or offgrid living- so we will start off slow. I expect we'll buy something that is not currently setup for solar, but our long-term goal is to convert to solar or at least supplemental solar. Is there also something to look for as far as being able to run a house on a generator? Do I ask if a house is designed to be able to run on a generator if the power goes out or is that something that I should expect is standard?

sorry for such basic questions, but again, Im new to this. Thanks!

[Frugal Upstate]

I don't have solar-so take what I say w a graIn of salt

I'd do some research on "passive solar heating" if I were you-learn about what to look for as far as the placement of the house, orientation of windows etc.  my house has lousy southern exposure-so we don't get much of any passive solar gain in winter AND I have very few windows suitable for keeping plants alive/overwintering them.

[cidermonkey]

Take a compass to verify south when you are looking.  Know your sunpaths for different seasons.  The passive solar principles are crucial to determining your energy consumption over the years, a well-designed and well-sited home and be kept comfortable with a fraction of the energy of a home poorly sited and designed.  The amount of energy you can make with pv is directly related to the amount of light that reaches the pv modules.  Listen to the two recent shows with Steven Harris on generators, any house can use them.  If you are going off-grid, check out backwoodssolar.com.  If that is too ambitious at the outset, you will be grid-intertied.  Be sure to consider water and soil at the same time as the solar resource.  Have fun homestead-hunting!

[Philip]

I second backwoods solar as a great resource. Request their catalog, it has several examples of different PV/offgrid system sizes and what they would typically power. Forget the all-electric house. Look for a house that has gas water heating and gas stove, or at least where it could be easily retrofitted. Optimally, look for a house with a creek or steam for micro hydro. Even a mere 100 watts of hydro adds up over 24 hrs. It's the cheapest per watt if you got the water. And of course, If you have running water on the property, you have a huge resource for gardening. We use a ram pump on our creek and get 1400 gal/day 24/7,365 without using any electricity.  Aspect is huge for both PV and passive solar. Get some sun charts for your latitude for site selection and orientation. I built our house from scratch to get the features I wanted but would consider buying a smaller house if it good siting and add a passive solar addition to augment the heating. Small two story homes are good candidates. In my case, property in our area that was offgrid (and we are only 1.5 miles from grid) was cheap enough to offset the cost of a PV system compared to comparable on grid homes in the area.   

[flippydidit]

Your eventual solar system can be as inexpensive or elaborate as you want/need.  However, the more energy efficient your house is, the less solar it will REQUIRE to do the job.  That is extremely important when you understand how expensive solar electric (PV) systems cost per kilowatt.

Answering your question about what to look for in a property is a fairly broad question to answer.  If you want a backup system, you'll need a battery storage area.  Your existing home wiring will be used, but many solar installations will need to run additional wiring (sometimes in your attic).  If the home is a small off-grid cabin, you could design it from the ground up to have smaller electrical needs.  If you're trying to retrofit a larger (modern) home the cost could be enormous.

Another thing to consider is annual solar insolation/irradiance (how much sun you get).  Doing a Google search with "annual solar insolation <your zip code>" didn't turn anything up for results when I tried it.

If you go to this website there is a calculator for your area (you'll have to choose a city you live near):

http://solarelectricityhandbook.com/solar-irradiance.html

Your ability to generate electricity or passively heat your home/water with solar is very much dependent on your annual insolation.  A loose analogy can be drawn to the different gardening zones/climates.  A home with a $30,000 solar PV system in Arizona might produce the same or more electricity than a $120,000+ system in Washington State.

A good explanation of insolation/irradiance can be found at:

http://en.wikipedia.org/wiki/Insolation

It isn't just the insolation either.  Colder climates produce less efficient solar systems.  With temperature drops, amperage efficiencies drop as well.  This is further reduced by snowfall which can obscure panels or even cause roof damage.  Solar panels weigh a lot.  Add snow burden to that and you could have roof failures (especially if not professionally installed).

You'll need the solar insolation numbers, as well as your required daily kilowatt hours to design your solar system.  I'd recommend checking out the many answered questions on the following forum when you're ready to design and build:

http://www.solarpaneltalk.com/forum.php?s=293514f15319a50620ad47c090bbb932

Off grid only topics:
http://www.solarpaneltalk.com/forumdisplay.php?28-Off-grid-electric-systems&s=293514f15319a50620ad47c090bbb932

There is a lot of planning and shopping around involved with solar systems, and many people think that this "green" technology is cheap.  It isn't.  Not by a long shot.  You need to consider that you may have to replace your batteries every 3-10 years.  With the price of batteries (and what they'll cost 3-10 years in the future), you'll come to understand that solar isn't the best choice for everyone.  It may be more cost effective to run a generator for your needs.  Do your research and decide.  Best of luck on your property search!

Hope this helps!

[fred.greek]

To obtain a chart of the solar path in your area, see the University of Oregon website:

http://solardat.uoregon.edu/SunChartProgram.html

It is of course not just the path of the sun, but what might be “in the way”, and your weather.
Are you going to track, or not?

Just thoughts, even with the greater amount of atmosphere due to the low angle, at 10 degrees above the horizon, there may be available up to 50% of the total solar power.  If your panels are two feet wide, to not shade each other on the E/W axis when tilted to only 10 degrees up from the horizon, they must be spaced apart nearly twelve feet.  If you limit your morning/evening aim to 30 degrees above the horizon the panels need to be spaced only four feet apart.  Depending upon factors such as your latitude, time of the year, and physical barriers, the difference between ten and thirty degrees may be a lot of solar sky-time missed.

Remember that if a solar panel is partially shaded, most lose a significant portion of their power generating capability, well beyond the percent of the panel shaded.

If you do NOT track at all, a key selection is the angle of the panels.  Are you going to align for maximum noontime collection for summer, winter, or the equinoxes?  If you align for the noon equinoxes, noon at the summer and winter solstices will be off by 23.5 degrees (only receiving 92% of potential power).  While someone with better math skills could calculate accurately, at a ballpark during the solstices when the sun is around 35 degrees east or west of the panel, you are only getting 50% or so of the available power.  A significant aspect for the summer solstice is that the sun rises and sets North of an East/West line.  Checking the Yuma Chart, for us optimistically it appears that the fixed panel would not even "see" the sun at due east until around 0840, and the sun would pass north of the panel at around 1520. (6 hours and 40 minutes exposure)

Broader, Mike Reynolds and his Earthship folks deal with other aspects of an “off the grid” home. 
http://www.earthship.com/
His three books have been available online at www.scribd.com, or ask you local library about an interlibrary loan.
Youtube has several video’s of what appear to be recordings of class sessions he has presented.