What that is equal to
🏠 46.7 thousand
homes powered for a year
at the US average of 10,500 kWh per household
🌍 182 thousand t
CO₂ avoided annually
displacing grid power at 0.371 kg CO₂e/kWh (EPA eGRID)
🚗 39.5 thousand
cars taken off the road
an average passenger vehicle emits 4.6 t CO₂e a year
⚡ 1.4 billion
electric vehicle miles
at roughly 0.35 kWh per mile
The pay-off
It pays for itself here. A panel on this roof delivers electricity at 8.5¢ a kWh against a local price of 12.4¢ — 31% cheaper than local power. The install is repaid after 16.9 years, inside the panel's 25-year life.
8.5¢ vs 12.4¢
cost per kWh: this panel vs the grid
levelised over 25 years including 0.5%/yr degradation
$982 million
to fit every building here
1,090,755 panels at $900 installed each
16.9 years
to break even
saving $60.5 million a year area-wide at today's price
Assumes $900 to install one 325 W panel — hardware, mounting,
microinverter, electrical work, labour and permitting — repaid only by the electricity it
avoids buying. No subsidies, tax credits, net-metering premium, financing cost or future
price rises are counted, and the figure is undiscounted. Electricity price is the
ID residential average (EIA, May 2026). A single panel is unusually expensive per watt because it
carries a whole array's fixed costs, which is why these numbers look worse than rooftop
solar generally does.
How this is calculated
| Buildings with roofs | 1,090,755 |
| × Panel rating | 325 W |
| × Annual yield per panel here | 449.2 kWh |
| Annual generation | 489,971,297 kWh |
Assumptions and limitations
- Yield is specific to this location: 449.2 kWh per panel per
year, from NASA POWER climatology transposed onto a tilted roof plane.
The same panel makes roughly 596 kWh in Phoenix and 265 kWh in Anchorage.
- Assumes a south-facing roof at a typical residential pitch, with a
~22% total system loss for soiling, shading, wiring, inverter, and heat.
- Counts every above-ground structure with a footprint of at least 20 m²,
so garages and outbuildings are excluded but barns and sheds of real
size are not. Building data is machine-derived and imperfect.
- No account is taken of roof orientation, obstructions, structural
condition, or whether the owner wants a panel.
Counties in Idaho
Metro areas in Idaho
Boise City, ID · 175 GWhCoeur d'Alene, ID · 40.1 GWhIdaho Falls, ID · 37.4 GWhLogan, UT-ID · 30.2 GWhTwin Falls, ID · 29.1 GWhSandpoint, ID · 18.6 GWhOntario, OR-ID · 19.6 GWhLewiston, ID-WA · 17.5 GWhPocatello, ID · 19.6 GWhBurley, ID · 16.1 GWhRexburg, ID · 13.3 GWhJackson, WY-ID · 13.4 GWhBlackfoot, ID · 13.6 GWhMoscow, ID · 9.76 GWhHailey, ID · 9.3 GWhMountain Home, ID · 7.66 GWh
Places like Idaho