So the thing is the economics of rooftop solar are a lot different than power station solar. The DOE has public data on how much utilities pay for electricity. In a market like mine, Southern California Edison isn’t an electricity generator, they buy power at about $0.02/kWh but then they sell it to the residential consumer for up to $0.32.
So clearly it’s a very different calculation. Regardless of that generators are building large scale solar arrays to sell power to the utilities at very much lower rates than what a rooftop owner pays to generate their own power. It’s just the rooftop owner can bypass a lot, and potentially all, of the utility and grid fees which are >90% of the cost. The other thing is that many utilities are hugely subsidizing this with net metering policies, which basically means the utility is acting as a huge battery for only the grid connection fee which, depending on the market, can be as low as $15 a month. Which basically seems to make products like the Tesla Powerwalls a really tough sell. Why pay $5000 for a tiny powerwall when, assuming you want grid connect anyway, the utility will be a way bigger powerwall for free?
So clearly it’s a very different calculation. Regardless of that generators are building large scale solar arrays to sell power to the utilities at very much lower rates than what a rooftop owner pays to generate their own power. It’s just the rooftop owner can bypass a lot, and potentially all, of the utility and grid fees which are >90% of the cost. The other thing is that many utilities are hugely subsidizing this with net metering policies, which basically means the utility is acting as a huge battery for only the grid connection fee which, depending on the market, can be as low as $15 a month. Which basically seems to make products like the Tesla Powerwalls a really tough sell. Why pay $5000 for a tiny powerwall when, assuming you want grid connect anyway, the utility will be a way bigger powerwall for free?