Currently solar power is getting much cheaper and more practical. Every now and then, I see a tech news article about a new breakthrough in solar that should b

Currently solar power is getting much cheaper and more practical. Every now and then, I see a tech news article about a new breakthrough in solar that should be ready for the market in the mythical "3-5 years" timeframe, then I never hear about it again. I'd be very happy to see some evidence that there's real, marketable progress being made right now that isn't marginal improvements to existing inefficient and expensive technology.