What doesn't move, however, is a suspended mass inside the seismograph, called the seismometer. During an earthquake, the seismometer remains still while the case around it moves with the ground shaking. Traditionally, the suspended mass was a pendulum, but most modern seismometers work electromagnetically.
Solar electricity costs about $10 to $12 a watt installed, though you may be eligible for state incentives. Check your utility bill to see your monthly usage. A robust solar electric system will cost about $20,000. You can spend as much money, to receive as much solar electricity, as you feel comfortable with.
Installing solar panels on one home costs about $20,000 to$50,000. Many states now offer discounts to families who want to install solar panels, so the actual cost is not that high. The average cost of electricity from coal-burning power plants is around 10 cents per kilowatt hour. A kilowatt hour is the amount of energy used if you leave a 100 watt light bulb turned on for 10 hours. The cost of electricity from a solar power plant is about 30 cents per kilowatt hour.