An idea for the future? No!
Renewable energy systems are available now, with many countries already generating a large percentage of their energy needs via renewable sources.
Wind turbines in Denmark supply the equivalent of about 42% of the countries electricity demand. And the Danish government announced the "Energy Strategy 2050" with the aim to be fully independent of fossil fuels by 2050.
Companies like Telsa energy have made giant leaps in the way solar power is collected and stored - making it now possible for any home to move off-grid and away from fossil fuels.
Not only is the technology available, Stanford engineers have developed a state-by-state plan to convert U.S. to 100% clean, renewable energy by 2050 view here.