Porcupines' quills, or spines, take on various forms, depending on the species, but all are modified hairs coated with thick plates of keratin, and embedded in the skin musculature.
Produce up to 400-Watt of power for free in your own back yard. The wind turbine will produce more power up to 400-Watts at 28 mph. If the wind dies down the turbine will continue to produce power in winds as low as 5.6 mph. This wind generator is used to charge 12-Volt batteries and mounts on any 1.5 in. Schedule 40 pipe.
Â£800 per Kilowatt Average. For a large, modern wind turbine (in the 1000 kW range) is approximately Â£800 per kW of electrical power to install. A 1000 kW turbine would be expected to produce 26,280,000 kWh in a year*, although this depends on the wind.