I assume you're on a pretty attractive net metering agreement? That's a huge system.

Unless you're consuming a significant portion of that, the payback rate is going to be pretty badly impacted by having such a large system for most people.

I consume about 17MWh a year between two EVs and a large heat pump for winter heating.

I will have overproduction now with the 2nd array. We do have net metering at about 80% of the cost on NEM 2.0. Our bill is split by transmission, generation, distribution and fees. We get 100% on transmission and generation and 25% on distribution.

https://www.energy.nh.gov/sites/g/files/ehbemt551/files/inli...