Original appliance-load data
Appliance-aware solar panel sizing dataset
Major electric loads can change solar sizing more than bedroom count. Under Watt My Roof's model, an electric water heater can add about 7 panels, an EV can add about 6 panels and a pool pump can add about 7 panels at five peak sun hours with 400-watt panels.
Published September 27, 2026
Download the appliance-aware sizing data
This CSV is intended for homeowners, local resource pages, journalists and energy educators who need a transparent planning reference. It uses Watt My Roof's public assumptions and should not be treated as a permit-ready design.
Download CSV: appliance-aware-solar-panel-sizing-dataset.csv
How many panels common appliances can add
The table uses 400-watt panels, a 0.80 performance factor and 100% offset of the appliance load. The count is rounded up because partial panels are not useful for planning.
| Appliance or load | Monthly kWh assumption | 3 sun hrs/day | 4 sun hrs/day | 5 sun hrs/day | 6 sun hrs/day |
|---|---|---|---|---|---|
| Refrigerator Everyday appliance | 55 kWh/mo | 2 panels | 2 panels | 2 panels | 1 panels |
| Washer Laundry | 12 kWh/mo | 1 panels | 1 panels | 1 panels | 1 panels |
| Electric dryer Laundry / electric appliance | 75 kWh/mo | 3 panels | 2 panels | 2 panels | 2 panels |
| Central HVAC Heating and cooling | 240 kWh/mo | 9 panels | 7 panels | 5 panels | 5 panels |
| Dishwasher Kitchen appliance | 25 kWh/mo | 1 panels | 1 panels | 1 panels | 1 panels |
| Electric water heater Water heating | 320 kWh/mo | 11 panels | 9 panels | 7 panels | 6 panels |
| Electric vehicle Transportation electrification | 260 kWh/mo | 9 panels | 7 panels | 6 panels | 5 panels |
| Pool pump Outdoor / pool | 300 kWh/mo | 11 panels | 8 panels | 7 panels | 6 panels |
| Heat pump Heating electrification | 450 kWh/mo | 16 panels | 12 panels | 10 panels | 8 panels |
| Induction range Kitchen electrification | 40 kWh/mo | 2 panels | 2 panels | 1 panels | 1 panels |
| Dehumidifier Moisture control | 45 kWh/mo | 2 panels | 2 panels | 1 panels | 1 panels |
| Hot tub / spa Outdoor / comfort load | 250 kWh/mo | 9 panels | 7 panels | 6 panels | 5 panels |
Common household scenarios
These are not full-home totals. They isolate major add-on loads so homeowners can see why future electrification plans should be included before comparing solar quotes.
| Scenario | Included loads | Monthly kWh | Panels at 5 sun hrs | System size |
|---|---|---|---|---|
| Core electric appliances | Refrigerator, Washer, Electric dryer, Dishwasher | 167 kWh/mo | 4 panels | 1.6 kW |
| All-electric water heating added | Refrigerator, Washer, Electric dryer, Dishwasher, Electric water heater | 487 kWh/mo | 11 panels | 4.4 kW |
| EV household | Refrigerator, Washer, Electric dryer, Central HVAC, Dishwasher, Electric vehicle | 667 kWh/mo | 14 panels | 5.6 kW |
| Pool and HVAC household | Refrigerator, Washer, Electric dryer, Central HVAC, Dishwasher, Pool pump | 707 kWh/mo | 15 panels | 6.0 kW |
| High-electrification planning load | Central HVAC, Electric water heater, Electric vehicle, Heat pump | 1,270 kWh/mo | 27 panels | 10.8 kW |
The formula behind the dataset
Annual output per panel assumptions
| Peak sun hours | Annual output per 400 W panel | Planning impact |
|---|---|---|
| 3 hours/day | 350 kWh/year | More panels needed |
| 4 hours/day | 467 kWh/year | More panels needed |
| 5 hours/day | 584 kWh/year | Middle planning assumption |
| 6 hours/day | 701 kWh/year | Fewer panels needed |
Watt My Roof publishes this as modeled planning data, not a quote or savings guarantee. If you cite the dataset, link to this page or the CSV and describe it as an appliance-aware solar panel sizing estimate using transparent assumptions.
Limitations
- Actual appliance use varies: household size, climate, equipment efficiency and behavior can change kWh materially.
- Sun hours are local: the same appliance load needs more panels in lower-sun locations and fewer in higher-sun locations.
- Roof fit is separate: panel count does not prove that panels fit around shade, vents, setbacks or structural limits.
- Utility rules matter: interconnection, export credits, batteries and system caps can change the best design.
FAQ
What is appliance-aware solar sizing?
Appliance-aware solar sizing estimates how major electric loads such as EV charging, water heating, HVAC, dryers and pool pumps change the electricity a solar system may need to offset.
Can one appliance really change solar panel count?
Yes. A high-use appliance can add hundreds of kWh per month. Under a five peak sun hour, 400-watt panel assumption, 300 monthly kWh adds about seven panels before roof, shade and utility review.
Is this dataset a solar quote?
No. This is planning data built from transparent assumptions. A final system design still depends on roof fit, shade, interconnection rules, panel model, inverter design, batteries, permits and installer review.
Why publish this as a dataset?
The data makes Watt My Roof's calculator assumptions visible and citable for homeowners, resource pages, journalists, local governments and energy educators.
This dataset extends Watt My Roof's calculator assumptions into a citable table. For full context, see the methodology page, the monthly kWh dataset and the appliance guide.