When you want to retrieve data from a database, you ask for the data by using Structured Query Language, or SQL. SQL is a computer language that closely resembles English, but that database programs understand. Every query that you run uses SQL behind the scenes.
The inverter turns the DC electricity generated by the solar panels into 120-volt AC that can be put to immediate use by connecting the inverter directly to a dedicated circuit breaker in the electrical panel.
Solar power is a clean, renewable energy source, yet it makes up less than 1 percent of the power used in the United States [source: USA Today]. Part of the reason more people aren't using solar energy to power their homes is the cost. Solar panels can cost $30,000 or more to install, an investment that can take 10 to 15 years to recoup [sources: Live Science, CNET News, Walsh].