When a business moves some of its power to open access, its DISCOM loses revenue it was counting on. Two surcharges recover it, and together they are often the single largest cost on open access power.
Cross-subsidy surcharge (CSS)
Industrial and commercial tariffs are set higher than the cost of supply so that homes and farms can pay less. When you buy power elsewhere, that support stops. The cross-subsidy surcharge makes up for it. It varies widely: published figures range from ₹0.60 a unit in Karnataka to over ₹2 a unit for some industrial categories in Maharashtra.
Additional surcharge
DISCOMs sign long-term contracts to buy power for their customers and must keep paying for that capacity even after you leave. The additional surcharge recovers those fixed costs. Karnataka’s published figure is ₹0.40 a unit from March 2026.
Who doesn’t pay them
Captive and group captive users are exempt from both under Section 42(2) of the Electricity Act 2003. That is why co-owning a plant usually lands ₹1.50 to ₹2.00 a unit cheaper than a third-party PPA.
Example
On 2 lakh units a month in Karnataka, CSS and the additional surcharge add ₹1 a unit, or ₹24 lakh a year. That is the amount a group captive structure would save the same factory.
Related: group captive, landed cost, DISCOM.
Sources
Figures last checked on 26 September 2026.