I feel the title here is misleading as it suggests that Google is investing in developing some sort of solar systems with this specific $75 million. But reading

I feel the title here is misleading as it suggests that Google is investing in developing some sort of solar systems with this specific $75 million. But reading the article, we see they are actually investing in funding a bank (finance company) which will be offering loans with interest for PV rooftop installations, for which they will receive payments with interest from the homeowners purchasing said systems at full cost. So they are investing in the same way that Chase invests in credit card debt by offering people credit cards, or that GM finance invests in cars by offering auto loans. The claim that the monthly loan payments will be "often less than paying for energy from the grid" is certainly false and I'd be willing to bet money that it will not be established that people are generating solar energy for less than the cost of buying it off the grid. Finally, if one was really interested in green technology, either installing a roof top solar hot water heater and/or a geothermal heat pump will save more energy than a rooftop residential PV installation will generate, but at a much lower cost.