By the way, at my location - sun and the wind will not be enought to power any device for a half of a year.
It's like this with any solar system. They are expected to take 12-14 years to pay off in most cases. But they last for almost twice that (or more), so the long term benefits are great. The short term are not.
In the US, you can also get tax rebates, though, that cover like 30% of the cost of your panels and installation. But again, the cost is great; you do this for the long haul, not to earn back your money in a year. If it were that simple, every house in the world would already have solar panels.