The price of wind systems on a per - watt basis depends on their size and output — they tend to become less expensive as the size of the system increases. (energysage.com)
Typically, for a small wind system, energy produced is used to offset a portion or all of the electricity at a site. (windustry.org)
Power Source - Some modern clocks use batteries, while others use the traditional mechanical winding system with weights and chains. (geekwrapped.com)