Solar Savings in South Carolina — 2026

What the 2026 numbers look like in South Carolina

The August 2026 EIA residential rate for South Carolina is 15.76 cents/kWh, 13.2% below the 18.16-cent U.S. average. Installed cost is 2.80 $/W, the labeled 2.80 $/W national modeling benchmark; sunlight uses the southeast humid-subtropical band planning band at 5.2 peak sun hours/day. With a below-average tariff and a benchmarked installed price, South Carolina shows why a national estimate cannot be copied into a state proposal. A statewide export-credit rule was verified for this state and is named below.

What actually moves the estimate in South Carolina

Holding a $150 monthly bill fixed, those inputs size a 6.45 kW array here against 6.06 kW at the national average, produce about 10,279 kWh in year one against 8,921 kWh, and put the interpolated payback at 13.8 years against 16.1 years. The 2.80 $/W price sits +0% relative to the 2.80 $/W benchmark.

That gap is arithmetic from published inputs, not a ranking of states and not an installer quote. Fixed monthly charges, non-bypassable charges, time-of-use periods, annual true-up caps, interconnection limits and a real bid all sit outside this model; the methodology page lists the omissions in full. Replace every default in the calculator below with your own figures.

Example estimates at three bill levels

All three rows hold the same assumptions (90% offset, a south-facing 20-degree unshaded roof, 0.84 derate, no battery, 3% rate escalation, 0.5% degradation, 25 years); only the monthly bill changes. The full default set and every equation are on the methodology page. Replace them in the calculator below with your own figures before treating any row as yours.

At a $150 monthly bill the model sizes a 6.45 kW array producing about 10,279 kWh in year one, needing roughly 355 sq ft of usable roof, with a gross cost of $18,053 and a net cost of $14,553. Year-one savings are $1,067, and the interpolated payback is 13.8 years.

South Carolina incentive and tariff stack

South Carolina: 25% state solar energy tax credit, capped at $3,500, with a carryforward. Confirm current-year availability before relying on it.

No separate production incentive was verified for this state in our November 2026 review; check DSIRE and your utility for local programs.

South Carolina: export crediting varies by utility and by the state's solar choice tariff.

Where these numbers come from

• Electricity rate: 15.76 ¢/kWh is the EIA Electric Power Monthly Table 5.6.A August 2026 residential value for South Carolina, reproduced verbatim. EIA flags 2026 values as preliminary. Table 5.6.B is a year-to-date series and was not mixed in.
• Installed cost: 2.80 $/W — National modeling benchmark (2.80 $/W) — not a measured state price.
• Solar resource: 5.2 peak sun hours/day, southeast humid-subtropical band (a planning band, not a station measurement). Use NREL PVWatts for an address-level figure.
• Export regime: South Carolina: export crediting varies by utility and by the state's solar choice tariff.
• Federal credit: $0. IRC section 25D was terminated for expenditures made after December 31, 2025 under Public Law 119-21.

How South Carolina compares with the nation and its neighbours

At the U.S. average of 18.16 ¢/kWh and a 2.80 $/W modeling benchmark, the same $150 bill sizes a 6.06 kW array with a $16,972 net cost and a 16.1-year payback. The neighbouring states below show how quickly the inputs change across a border — and why copying a national estimate into a South Carolina proposal is a mistake.

What to verify first in South Carolina

• Both sides of the meter matter. At 15.76 cents/kWh, close to the 18.16-cent national average, neither the avoided retail rate nor the export credit dominates; a change to either can shift the 13.8 years payback. Model both before agreeing to an array size.
• Price is a benchmark here, not a measurement. No verified state-level marketplace average was available, so the model uses 2.80 $/W and says so on the page. Three written cash quotes replace that assumption with a real number.
• Confirm the export rule version. A statewide rule was verified for this state and is described above, but eligibility windows and caps move: check the version that applies to your interconnection date.
• Check the incentive cap and carryforward. A state credit is applied in this model; confirm the statutory cap, whether unused amounts carry forward and whether the program has a waitlist before treating it as cash.

Before you sign in South Carolina

• Get your utility's export credit in cents per kWh, in writing, and check whether it is locked.
• Compare at least three written quotes on $/W before incentives, with cash and financed prices separated.
• Confirm the South Carolina incentive stack on DSIRE and your utility program page — caps, carryforwards and waitlists change.
• Ask for a bill-impact analysis built on your 12 months of interval data, not a single annual average.
• If a proposal still shows a 30% federal credit on a 2026 installation, treat every number in it as unverified.