RPS obligation calculator
One supplier's certificate requirement, shortfall and the cost of covering it.
A teaching aid, not a state rule. The presets are invented, except the two New Jersey buttons, which use percentages from a September 2026 proposal with invented sales. Enter each tier as the state lists it. Do not enter the solar share twice if your state counts it inside the main tier. Use a comma or a point for decimals, for example 4,35.
| Result | Value |
|---|---|
| Obligated sales, MWh | |
| Main tier: certificates required | |
| Main tier: shortfall | |
| Main tier: surplus (may be bankable) | |
| Main tier: cost of covering the shortfall, USD | |
| Solar carve-out: certificates required | |
| Solar carve-out: shortfall | |
| Solar carve-out: surplus (may be bankable) | |
| Solar carve-out: cost of covering the shortfall, USD | |
| Total cost of covering both shortfalls, USD | |
| Shortfall cost per MWh of retail sales, USD | |
| Solar kWdc that would make the solar requirement in a year |
Requirement = obligated sales times the target. Obligated sales = sales times (1 minus the exempt share). Certificates are not rounded. Cost = shortfall times the cheaper of market price and ACP, or the market price if no ACP is allowed. Real rules differ on eligibility, banking, rounding and timing. The kWdc line is a sizing guide for one year, not a build target, because existing projects and banked certificates also count.