Have been spending time over the past few days at Wife's behest, doing some ballpark power calculations for a domestic power system that is independent of the grid. No matter which way you cut it, Solar doesn't quite add up. The cost / benefit analysis still comes up short even in the medium to long term. Small Wind turbines don't give anywhere near the power required to heat and light the average home. This is including factoring in the use of Ground heat pumps and various types of heat exchangers.
A moderate Solar panel, for my calculations I picked a model manufactured by Mitsubishi rated at 120w with a generating area of about 0.6 square metres. According to the sources I've seen, even on sunny days you are likely to get no better than 30w per panel; possibly as low as 10w per panel on cloudy or winter days, and that's just during daylight. To get even close to a houses daily power requirement my back of a cigarette packet calculations tell me I need 20 panels at a cost of about CDN$13,000 in total. Then there is the cost of the wiring and the inverter, which bump that up to a grand total of roughly CDN$22,000. This is without factoring in the cost of a solar powered hot water system and ground heat pump, which I estimate (Ball park figure only) at around the CDN$10,000. Not sure about the installation costs, but I'm sure the price tag hovers around CDN$5-6,000 at the very least. To be on the safe side, let's call it a round CDN$40,000 or £20,000 for a system that will only give value for money if the sun shines a lot.
Working on a yearly energy bill of around CDN$2000 I've worked out that amortising the installation / maintenance costs of a solar / wind energy solution will take the best part of 20 years, minimum. Mind you, that's for heating, cooking, hot water, everything; and relies very heavily upon us investing heavily in high value insulation installation / low energy house design. That entails another level of cost, but only (From what I'm told) increases the build price by 15 - 20%.
Now there is something I've been looking at that will provide more than enough electricity for our and our children's and grandchildren's needs, given the right site. Good old fashioned Hydro electric power. Micro systems retail at under CDN$10,000, allowing another CDN$10,000 for permits, engineering works etc and can provide power 24 / 7 being largely independent of the weather, excluding drought of course. System life tends to be measured in decades with only moderate maintenance, and can pay for itself within 10 years.
On the surface, a micro hydro plant looks the better solution. This bears further investigation. That can wait for another day. I have a small but significant headache and think I should get outside in the fresh air and sunshine. Good idea.