It sounds like they are trying to create a market. They are providing financing, so they will actually make money. The initial money plus the interest can be applied to the next 12,000 homes, for example, then to 15,000 home, then to 25,000 homes... This can be done indefinitely...or at least for a couple of decades.

The market of suppliers will grow to meet the consumer demand, and suppliers will invest some of their profits into R&D and manufacturing. And I believe Moore's Law applies to the manufacturing of solar cells.

http://spectrum.ieee.org/tech-talk/semiconductors/devices/ph...

Create a market and let private industry handle the rest. Space, robotics, cheap energy, etc.