I do think the previous poster stated solar panels.
With a limited income, it is an expensive purchase, but an investment that in the right environment pays off.

With a lot of sun comes great benefits with solar panels. Some solar panels companies here in Europe (maybe the same is true in CA) will even give you the panels for free, install it for free, but they keep all the "profits" after usage.
You just get the reward of never having a electricity bill ever again. It's worth it if you don't want to worry about the investment factor.

There is also wind turbines, but I don't know as much as those.

One thing to consider though is if you can save money by using less electricity.
Undervolting in the right place I've seen really powerful GPU's drop to half their normal usage by massively lowering the voltage going to the memory and obviously declocking the memory aswell. Not like you need it for Mining anyway.

Do abit of Google searching and i'm sure with the above information you can find something that works out for you.

....................................................Solar...................... ........................

There are fees at nearly all exchanges.  The fee for selling will vary as higher volumes get a lower rate.  Starting out you are at 0.6%.  There may be additional fees when withdrawing those funds as wel..  For instance, the least method is Dwolla at $0.25 per transaction.  Wire transfers are much more expensive.


Here's a post that describes a ton of different ways people are using bitcoins:
 - http://bitcointalk.org/index.php?topic=78755.0