We had concluded that a sufficiently beefy PV solar system to keep up with our cloudy winters would be prohibitively expensive, costing twice as much or more than hooking up to the grid. However, it rankled to spend $11,000+ just for the privilege of paying a power company for each kwh after that. Especially considering that it will likely be more than 11 grand by the time we get around to building with the rapidly increasing price of copper.
So I looked at the feasibility of solar again and it actually appears it may be doable. I used this site to calculate the minimum amount of power we would use on a winter day and arrived at a 100 kwh/month figure. I didn’t really look at it very closely or I would have seen that by not using a dishwasher on cloudy days and washing by hand instead we could cut that by half! Half! So rather than requiring a 2000 kw system we only would require a 1000 kw system. The cost of a smaller system is only slightly more than the cost of hook up to the grid. Hopefully it might even be comparable or less by the time we get around to building. PV should come down in price as the technology is developed and electricity is unlikely to drop in price and may even raise steeply if the government stops subsidizing hydro-electric.
It will take a bit more research into our actual building site (bottom of a valley) and the solar potential as well as costs of maintaining the system but a grid free house might actually be possible.
