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- Cash purchase & lease / finance projections
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Cash purchase
Pay up front, claim the federal tax credit and utility incentive in year 1, then collect electricity savings and SREC income for the life of the system.
Example NPV $3,241 · ROI 2.0%Lease / finance
Put the tax credit toward the down payment, finance the rest, and see whether the energy value beats the monthly payment every year.
Example NPV ($7,916) · $814/moSummary & charts
Cumulative savings, payback, annual cash flow and present value for both options on one page.
Four charts · one verdictHow it works
- Set up PVWatts. Enter your location, weather data and system settings on PVWatts setup.
- List your panel arrays. Enter the panel count, azimuth and slope of each roof plane on Panel arrays. PVWatts V8 calculates each array's yearly kWh and feeds both models.
- Set your electricity rate. Enter panel degradation, your electricity price and how fast it rises.
- Add incentives. Federal investment tax credit, a one-time utility incentive and SREC trade value.
- Pick a model. Cash purchase or lease / finance — or both — and read the year-by-year projection.
- Save & compare. Register free to save a model; subscribe to keep up to 10.
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