Thursday, July 30, 2009

Learning about Wind and Solar Power

Let's say you'd like to find out if solar panels or a wind generator would be a good thing to buy. Where do you start? From personal experience, I can tell you that the Yellow Pages is a waste of time. 9 out of 10 companies listed under "solar" are either "out of service", don't answer their phone, don't sell anything "solar", or is not sure and will have to get back to you. The tenth one is a crapshoot. So where do you go to learn about these promising power sources?
I talked to one fellow in my Yellow Pages search. He couldn't help me business-wise, but he did steer me to a place where I could learn all about solar and wind power. Home Power Magazine is a wonderful source of information and advertising. There are nuts-and-bolts articles, apples-to-apples comparisons, and even make-it-from-scratch-with-old-car-parts articles. You can buy a paper subscription or an online subscription. If you get the online sub(about $10), you can download all past issues in their archive. I recommend it. Go there now.

Tuesday, July 14, 2009

The Underside of Underground

I like the advantages of earth-sheltered construction and I don't want to build any other way. There are some disadvantages, however, and they should be considered.
In order to take advantage of the sun's heat and to mitigate the effect of cold winter winds, all the glass should be on the south face of the building. The window overhangs should be designed so that the inside is shaded in summer and gets full sun in winter. The problem here is that the best scenery and view might not be to the south. Also, building on the north side of hilly land might not give you enough sunlight. And the constraints of efficient passive solar design definitely restricts the architectural design. The WOW factor can become BOW WOW.
Most people have programmable thermostats to control temperatures in their homes. Above-ground homes are subject to wide swings in temperature, but underground homes keep a constant temperature because of the thermal mass of the structure. That flywheel effect makes it very difficult to change the inside temperature of an underground house. So it's best to pick one temperature and stick with it summer and winter.
The biggest disadvantage of earth-sheltered construction is cost. It is THE reason why above-ground homes are still built. As a rough estimate, I'd say that underground homes cost 50% more than above-ground homes. The beefy structure is one reason, but the biggest wallet-shocking surprise comes from excavation. Moving dirt is hugely expensive.
Oh yeah, and cell phones don't work underground. I have to walk outside to use mine.