Peter_s,
Apologies to CW in advance on going slightly OT... do the heatpumps generate electricity or only generate air/water-heating capacity? I have yet to find a heatpump which can generate electricity well without having the input significantly above ground temperature. Also, from what I have read over the past few years, in colder climes, boring deep and sinking "U tubes" gives better energy efficiency than digging horizontal trenches with a backhoe (which is obviously a lot cheaper); that said, it is obviously not a bad idea in the desert (or in places where the bedrock is very shallow).
Back on topic...
If you just want a system to generate electricity to cover the audio, using efficient speakers and matched 'small' amps will go a LONG way to making it possible, but the first 100 watts of solar installation is the most expensive (per kWh). If you have a large property in windy area, using mini windmills plus a bank of batteries can be a way to generate smallish amounts of electricity. If you want to use "green" power to cover 2kW of usage, then you are probably talking upwards of $10k of kit plus further installation costs. If you want 2kW for the audio and another several kW for the rest of the house, it is a fair bit more.
Apologies to CW in advance on going slightly OT... do the heatpumps generate electricity or only generate air/water-heating capacity? I have yet to find a heatpump which can generate electricity well without having the input significantly above ground temperature. Also, from what I have read over the past few years, in colder climes, boring deep and sinking "U tubes" gives better energy efficiency than digging horizontal trenches with a backhoe (which is obviously a lot cheaper); that said, it is obviously not a bad idea in the desert (or in places where the bedrock is very shallow).
Back on topic...
If you just want a system to generate electricity to cover the audio, using efficient speakers and matched 'small' amps will go a LONG way to making it possible, but the first 100 watts of solar installation is the most expensive (per kWh). If you have a large property in windy area, using mini windmills plus a bank of batteries can be a way to generate smallish amounts of electricity. If you want to use "green" power to cover 2kW of usage, then you are probably talking upwards of $10k of kit plus further installation costs. If you want 2kW for the audio and another several kW for the rest of the house, it is a fair bit more.