If that person lives where I do, the local power company has stupidly high rates for doing that. The only real way to save is to go completely off grid. There are two plans, one pays you almost nothing for the excess solar produced, the other charges you “high demand” rates if you exceed some arbitrary usage number at your peak even if you produced all the power yourself. It’s so freaking confusing for no reason other than to punish you for trying to offset your power bill with solar energy.