If approved, the monthly bill of a residential customer using 1,000kWh of electricity would increase $3.91 in phase 1, $3.77 in phase 2 and $4.01 in phase 3.

The company said that its base rate filing is primarily driven by the costs associated with complying with governmental regulations – particularly those related to protecting the environment.

Kevin Marsh, president of SCE&G, said: “Recognizing the financial challenge that this increase will represent for many of our customers, we’ve asked the commission to phase in this increase in three stages over the next 18 months. We believe the phase-in approach balances the impact on our customers with the company’s need to recover its costs.

“We are committed to conducting business in an environmentally sensitive manner. However, ensuring compliance with ever-increasing governmental regulations comes with a price tag, and it’s getting steeper all the time. This rate increase request is a concrete example of that fact. Our rate application reflects the recovery of expenditures of more than $700m on federally mandated environmental and safety initiatives.”