South Dakota solar calculator

Live production from NLR (formerly NREL) PVWatts V8. South Dakota has NO statewide net metering — this is the structurally weakest US state for export economics on the calculator. SD PUC-regulated utilities (Xcel Energy SD, Black Hills Energy, NorthWestern Energy) must interconnect distributed generation but are only required to PURCHASE EXCESS at AVOIDED COST — about $0.04/kWh representative (range $0.03-0.05). NO retail banking, NO 1:1 monthly netting, NO annual true-up at retail. Self-consumed solar offsets full retail (~$0.1175/kWh) by not drawing from the grid; only exports incur the avoided-cost rate. There is no 1:1 era to lose — SD simply never had statewide net metering. Co-ops and municipal utilities are NOT bound by PUC rules and may voluntarily offer something net-metering-LIKE for very small residential systems, but it varies — verify your specific utility in writing if you are not on an IOU. No utility selector; single editable retail and export rate. Federal §25D = $0 for systems installed after Dec 31, 2025 (OBBBA repeal, signed July 4, 2025). NO state income tax credit (South Dakota has NO state income tax at all — no residential solar income credit can exist). Property tax EXEMPT and CONTINUOUS under SDCL 10-4-44 — the first $50,000 OR 70% of assessed value (whichever GREATER) of a renewable-energy system under 5 MW is exempt from real property tax; for a typical residential install (under $50k total system cost) this is effectively a FULL permanent exemption with no 5-year sunset. Sales tax NOT EXEMPT for residential — SD state sales tax about 4.2% (plus local, combined about 5-6.5%) applies to equipment and labor; a sales exemption exists ONLY for commercial / community systems over 5 MW (does NOT apply to residential rooftop); about $850-1,300 sales tax on a $20,000 system. NO SREC market, no RPS (only a voluntary objective). NO statewide battery rebate. Install pricing about $2.50-3.00 per watt (modeled at $2.75 default, editable). Typical solar-only payback 17-23 years with federal $0 and avoided-cost-only export. Sources citing about 9-15 year payback assume BOTH the dead 30% federal credit AND retail net metering — NEITHER applies (SD has no net metering, federal is 0). Self-consumption and batteries are the ONLY way the dollar math works. STRUCTURAL NOTE: this is not a forward "risk" — SD's weak export economics are ALREADY CURRENT LAW and have been for years. The honest framing for a 2026 SD buyer: solar is a self-consumption + resilience purchase, not an export-ROI purchase. Defaults: south-facing roof mount, 20° tilt, 14% losses.