The seal around our guest bath had been cracking up for a while, and like a walrus at a Tupperware party I’m always happier if I have a good tight seal. The caulk was old and shriveled and generally of poor quality, so I decided I’d have a go at redoing it myself. Home Depot is the place to go if you’re looking for caulk on a Saturday afternoon. There were various scraping options ranging from razor blades up, so I picked out a good sturdy tool.
Once the paperwork started, I learned that our house was sufficiently old that it would need to pass an energy audit to qualify for Austin Energy’s incentive programs. I completely understood the reasoning, too. If you want to save money and cut energy consumption, efficiency measures are almost always the most cost-effective thing you can do. So before you even think about solar power, you should make sure you’ve sorted out all of the following:
Costing a solar system is complicated; there’s just no getting away from that. So I’m not going to present a detailed cost breakdown; instead, I’ll outline a few of the complexities. First of all, solar panels vary in efficiency. Higher efficiency panels generate more power per unit area, but they also cost more. So do you buy more panels, buy better panels, or aim to use less electricity? Similarly, the inverter which turns DC electricity from the panels into AC has a certain capacity and efficiency, and there are lots of companies making them to all kinds of specifications.
The first working solid state solar cell was developed in 1883 by Charles Fritts. Just 1% of the solar energy hitting the cell would be converted to electricity, and the cell was made from selenium with a thin layer of gold, making it far too expensive. It wasn’t until the development of silicon semiconductor junctions in the 1950s that solar cells started to become economically practical. Bell Labs developed a silicon-based solar cell with about 6% efficiency in 1954.