Because they are usually required to pay customers a lot more for feed-in power than they can generate it for, with no allowance for their internal cost overheads, etc.
Absolutely false -- horribly false.
On a day-to-day and month-to-month accounting basis, my utility (Salt River Project in Arizona) gives me a kWh-for-kWh credit. If I generate 20 kWh during the day, use 15 kWh during the day, and another 5 kWh during the night, I have net zero usage.
Surpluses are carried over day-to-day and month-to-month. If I have a net debit at the end of the month, I'm charged the regular rate for that electricity. If I have a surplus, it's carried over to the next month.
Once a year, in the spring, if I have a net surplus, SRP credits my account and resets the surplus to zero. And I generate about half again as much as I consume -- enough to power my not-yet-purchased electric vehicle -- so they credit me a fair amount every year. It's enough to pay the basic connection fee for about half the year, in fact, so I only even pay that for about six months per year.
But.
Rather than crediting me at the $0.12 / kWh typical residential retail rate, or the $0.25+ / kWh they purchase peak summer power (which is when I'm generating most of my surplus electricity), they pay me about $0.02 / kWh.
By my rough back-of-the-envelope calculations, they're now profiting from me almost as much as I used to pay them in total. As in, what used to be their gross receipts from me is now their net.
What business wouldn't be thrilled with such a business model?
So, do please stop spreading the lies of the Koch Brothers. The poor widdle utilities aren't being hurt by the solar meanies -- quite the opposite. They're making money from us, hand over fist.
They're just a bunch of greedy sick fucks who want to roast the goose that's laying the golden eggs, is all.
Cheers,
b&