I am shopping for alternative power source as diesel powered generators are becoming too expensive and noisy
Your best bet is going to be Geothermal. It's cheap, reliable, and can be used 99% of the time. That is if you are thinking solely of hot water /space heating and cooling A wind turbine will set you back slightly less cash but it is also limited to factors such as: - if the wind isn't blowing with enough velocity, then the turbine isn't spinning (cut-in speed) which means the turbine isn't producing 100% of the time. -your location may not be suited for wind harvesting( not enough wind duration per year) -the bigger the generator, the larger the diameter of the wind swept area. I don't think you would want a 7MW +400' diameter turbine in your backyard(source below). If you are thinking of electrical needs then solar PV may be another option to invest in. Either way, talk to a renewable energy specialist about scouting your area for efficiency before you make a decision.
Wind turbines come in all sizes these days - up to megawatts I believe.
largest wind turbine is 6 MW. you can get them in any size from 1 kW up to 6 MW. .
A typical home-sized wind turbine generator is only about 10 kW, and costs about $30k to purchase and have installed.
