Solar and battery
Should solar happen now, and on which roof? Is a battery worth it? ROOF answers both from your bills and your roof, not from a sales target.
Roof + solar decision
Roof first, then solarAdd solar any time later on a new roof.
The roof has 3–7 years left. Panels will need to come off for a reroof, about $4,800.
Mounts flashed into the new roof once. No removal later.
Replace the roof first so the panels never have to be removed and reinstalled. Estimated avoided future cost: $4,800 Projected
Solar on the new roof
Estimates- Usable roof area
- 683 sq ft
- Good planes
- Main south, East hip, Garage south
- Average shading on those planes
- 12%
- System size
- 6.4 kW (room for 12.3 kW)
- Annual production
- 7,209 kWh
- Share of your use
- 74% of 9,800 kWh
- Installed cost
- $18,240
- Incentives assumed
- None
- First-year savings
- $1,110
- Simple payback
- 16.4 years
- 25-year savings
- $35,497
Uses your 12 months of bills (0.19 $/kWh retail, 0.10 $/kWh for exported power), 2.5% yearly rate increases and 0.5% panel degradation. Check current federal, state and utility incentives before you sign; ROOF assumes none.
Battery
Don't buy- Installed cost
- $12,000
- Expected annual benefit
- $190
- From backup power
- $68
- From time-of-use rates
- $0
- From using more of your own solar
- $122
- Payback
- 63.2 years
- Warranty
- 10 years
Economics are weak for this home. It would take about 63.2 years to pay back a battery warrantied for 10. Outages here are short and rare, and there is no time-of-use rate to exploit.
This would change with a time-of-use rate, frequent long outages, or someone at home who depends on powered medical equipment.