WEBCurrent Rates. 04/01/23 First 3 therms or less Over 3 therms, per therm. $39.51 $0.2074. $39.51 $0.2242. S.C. 21, 17-21 – Rate 1 – Less than 1MW Monthly usage First 10 therms or less Over 10 therms, per therm (Apr – Oct) Over 10 therms, per therm (Nov – Mar) Monthly usage First 1 therms or less Next 199 therms, per therm Over 200 therms ...