A 1099 issued to customer by utility
I believe that happens only if you "make" more money from selling to the grid than you pay. In other words, if the utility gives you money it's taxable income.
What little I've been selling to the grid in Alabama since September of last year, at a much lower rate than I pay when I buy power from the grid, hasn't generated a 1099. It's treated as a reduction in my expense (lower power bill, not negative power bill where the utility sends me money).