The tariff your neighbour is on may be closed
The Energy Freedom Act, Act 62, signed on May 16, 2019, required the Public Service Commission to establish a solar choice metering tariff for customer-generators. Rates approved for Duke Energy Carolinas, Duke Energy Progress and Dominion Energy South Carolina became available to consumers applying for new service on or after June 1, 2021 and are available for ten years.
Existing solar customers who enrolled earlier continue to receive one-to-one compensation into 2029 depending on when they initially enrolled. That is a long tail of households on a better arrangement than a new applicant can get.
So treat any payback figure from a neighbour, a local review or an article written a few years ago as describing a different product. They are not being misleading; they are on a different tariff.
Ask your own utility directly which arrangement applies to a new residential solar customer at your address, and get the answer in writing before you accept any projection built on it.
Under solar choice metering, timing matters
The value of exported power under solar choice metering is tied to time-of-use rates. That is the substantive change from one-to-one crediting, where an exported kilowatt hour offset one you bought later at the same price and timing barely mattered.
Now what your generation is worth depends on when it happens and when your household consumes. A system that produces heavily at midday while nobody is home is a different financial proposition from the same system in a house with daytime occupancy.
Ask your installer which specific rate their projection assumes and to show the self-consumed share of production explicitly, valued separately from what is exported. A model treating every kilowatt hour as equally valuable is describing the old arrangement.
It also makes free changes worth something. Running laundry, dishwashing and any vehicle charging in daylight raises the share you consume as it is generated, and unlike equipment it costs nothing to adjust.
The state credit is what carries the return now
With the federal residential credit gone and one-to-one crediting closed to new customers, the South Carolina state credit does more of the work than it used to. It is 25 percent of total system cost up to $35,000, claimed on Form TC-38.
The annual limit matters: you may use only $3,500 of the credit in a year, or 50 percent of your state tax liability, whichever is less, with a 10 year carryforward for the excess.
Ask a tax advisor how much of that you would realistically use given your own liability, and ask any installer to show the credit year by year as it would actually be received rather than as a single deduction from the price.
The 30 percent federal Residential Clean Energy Credit under Section 25D expired for property placed in service after December 31, 2025, so check any projection line by line for it rather than trusting a summary figure.
The state credit, and how much of it you will actually use
South Carolina offers a state income tax credit of 25 percent of the total system cost, up to a total credit of $35,000, claimed on Form TC-38. That headline is genuinely generous and it is the main reason solar still works here now that the federal residential credit has gone.
The limit that decides what it is worth to you is annual. A taxpayer may use only $3,500 of the credit in a year, or 50 percent of their state tax liability, whichever is less, and the excess for each facility can be carried forward for 10 years.
So a household with modest South Carolina tax liability may not use the whole credit within the carryforward period. That is not a reason to avoid it, but it does mean the number in a sales presentation and the number you receive can differ substantially. Ask a tax advisor how much you would realistically realise given your own liability.
The 30 percent federal Residential Clean Energy Credit under Section 25D expired for property placed in service after December 31, 2025, so a cash or loan purchase now receives no federal credit. Section 48E survives at 30 percent for third-party owners under leases and power purchase agreements, so ask any such provider what they claim and what of that value reaches you.