Home solar guides
How many solar panels do I need? Sizing from your electric bill
A step-by-step way to size a home solar system from your annual kWh, daytime use and local sunshine, with real size-vs-payback tables for four states.
Is solar still worth it without the 30% federal tax credit?
The 30% federal solar credit is gone for new systems. We ran payback for every state without it, and compared it with what the credit used to do.
Net metering vs. net billing: how export credits change payback
How much your utility pays for exported solar power can add years to payback. We compare full, half and quarter-retail credits in every state.