A working model to explore what it takes to power a home with solar & batteries — and what happens when you add big loads like bitcoin mining or EV charging. Adjust anything below; everything recalculates live. Figures are ballpark planning numbers, not an engineering design.
1
The four numbers that drive everything
Every solar decision comes back to these. Get comfortable with them and the rest of this page is just arithmetic.
kWh vs. kW
kW is a rate (how fast you draw power right now). kWh is an amount (energy used over time). Your daily need is measured in kWh/day; your equipment is rated in kW.
Peak sun hours
Not daylight hours — the equivalent hours per day of full-intensity (1000 W/m²) sun. A region with "4.3 peak sun hours" might see 14 hours of daylight but only 4.3 hours' worth of full-strength sun.
System losses
Wiring resistance, inverter conversion, panel heat derating, dust, and imperfect angle typically cost 15–25% of rated output. This model uses a 0.80 derate by default.
Depth of discharge & autonomy
Batteries shouldn't be fully drained (10% is reserved here). "Days of autonomy" is how many cloudy days in a row you want to ride out on stored charge alone.
2
Build your loads
Start with the home. Flip on mining or EV charging to see how they change the picture — leave both off to see a plain whole-home system.
Whole-home baseline
US average is ~29.6 kWh/day (10,791 kWh/yr per household, EIA). A well-insulated efficient home can run 15–20 kWh/day; a large home with electric heat, a pool, or a workshop can easily exceed 50. See the appliance table below to build your own estimate.
Bitcoin mining rig
ASIC miners run flat-out, continuously, with almost no daily variation — the opposite load shape from a house. One S21 running 24/7 uses about as much energy as 2–3 average homes combined.
EV charging (Tesla Model 3)
Estimated at ~250 Wh/mile. The charger's kW rating only matters for a few hours while plugged in — it doesn't add to your all-day baseline the way mining does, but it does affect the peak-load number below if it overlaps other big draws.
3
Your climate
Sun hours vary a lot by region and by season — this is usually the single biggest lever on system size.
Sizing for winter (the default here) is the conservative, off-grid-honest choice — summer surplus is a bonus, not something to plan around. Effective peak sun hours used below:
4
Results
Everything above rolls up into a system size. These are planning-grade estimates for comparing scenarios, not a permit-ready design.
Total daily energy
–
kWh / day, all loads
Peak simultaneous load
–
sets your inverter size
Solar array needed
–
kW DC
Battery bank needed
–
kWh usable
Where the energy goes
Array sizing assumptions
Battery sizing assumptions
Rough cost, before incentives
Panels + install
–
~$2.60/W installed, 2026 avg
Battery bank
–
~$998/kWh usable (Powerwall 3 class)
Total system
–
excludes mining/EV hardware itself
Reference tables
Typical appliance draw
Appliance
Running W
Fridge (ENERGY STAR)
100–200
Central AC (3-ton)
3,000–4,000
Window AC (10k BTU)
1,000–1,200
Electric water heater
4,500–5,500
Electric dryer
1,800–5,000
Electric range/oven
2,000–3,500
Dishwasher
1,200–2,400
Washing machine
350–500
Microwave
750–1,100
Well pump (½ HP)
800–1,050
Space heater
1,500
55" LED TV
70–120
LED bulb
8–10
Peak sun hours (annual avg, selected states)
State
Hrs/day
Arizona / New Mexico
6.0–6.5
California / Nevada
5.5–6.0
Texas / Florida
5.0–5.5
Missouri / Kentucky / Tennessee
4.3–4.6
Virginia / Maryland
4.4–4.5
Illinois / Iowa / Wisconsin
4.2–4.4
Ohio / Pennsylvania / W. Virginia
4.1
Michigan
4.0
Pacific NW / New England
3.0–3.5
National average is about 5.0 peak sun hours/day. Winter daily solar gain typically runs 25–50% below the annual figure — the "Winter" season option above uses a 35% cut as a middle-of-the-road planning number.