[philipkglass]

The same link says:

The Section 48 commercial credit can be applied to both customer-sited commercial solar systems and large-scale utility solar farms. The rate is effectively at 30% until Treasury issues guidance on new wage and apprenticeship standards. Two months later, the rate will be at 6%, with an additional 24% (for a total of 30%) available for meeting these new labor standards.

So utility-scale solar farms can get the same 30% credit as rooftop solar. They're both tax-advantaged compared to (e.g.) building a new gas plant, but the rooftop credit isn't any higher, at least not on the federal level. Self-consumption from rooftop solar may avoid other taxes, like sales tax, but in many states there is no sales tax on residential electricity to begin with.

[sokoloff]

The interesting question of there being a subsidy for rooftop solar is the difference in subsidy to me between my roof having solar panels or my roof not having solar panels, not between my subsidy for my roof having solar panels or someone else's for their field having solar panels on it.