About SolarSized

SolarSized turns how much electricity you use into a solar and battery plan: how many panel watts, how many kWh of battery and what size inverter. It covers every state, common appliances, outage backup and sizing guides for homes, cabins and RVs.

How the numbers are made

• Sun hours are state annual averages derived from NREL PVWatts v8 (now run by the National Laboratory of the Rockies). Winter is lower, so off-grid systems should be sized for the worst month.
• Panel watts = daily Wh ÷ (sun hours × 0.75). The 0.75 system derate covers temperature, wiring, inverter and soiling losses.
• Battery kWh = daily Wh × days of backup ÷ (0.9 × 0.9), allowing for 0.9 depth of discharge and 0.9 inverter efficiency. Inverters are sized at least 1.25 × the running watts of the appliances you pick.
• Usage figures come from EIA, ENERGY STAR and manufacturer data, cited where they are used.

The full formulas and assumptions are on the methodology page.

Who runs SolarSized

SolarSized is published by EYEVUE Ventures, an independent publisher. It is not a solar installer, does not sell systems or collect leads, and is not affiliated with any panel, battery or inverter maker.

How the site makes money

Some product links go to Amazon, and as an Amazon Associate we earn from qualifying purchases. Any other program will be named on the affiliate disclosure page. Affiliate links and any labeled sponsor placement never change a calculation.

Fine print

SolarSized gives planning estimates, not engineering, electrical or financial advice. Have a licensed installer or electrician design and permit any grid-tied, roof-mounted or permanently wired system, and check incentives with the program that offers them.

Contact and corrections

Questions, corrections and partnership inquiries: eyevueventures@gmail.com. If a number is wrong, send the page URL and the source and we will fix it. How we handle data is on the privacy policy page.