Operating profits at Scottish Gas Networks grew by just over 9% to £169 million last year.
The company which manages Scotland's pipe network and gas meters increased revenue from £350 million to £357 million for the 12 months to March 31, 2020, which it put down to inflation.
SGN put that largely down to inflation and said the potential for further profits had been capped by Ofgem regulations.
It increased its spending on replacement of iron pipes with polyethylene ones from £70 million to £76 million. SGN said this had contributed to reducing gas leakage by 4%, the equivalent of 31,492 tonnes of CO2.
Its directors' report said: "The reductions are largely achieved through our iron mains replacement programme, optimising and driving down operating pressures in the network, gas conditioning and investment and innovation."
SGN is owned by a consortium of SSE and subsidiaries of OMERS Administration Corporation, Ontario Teachers' Pension Plan Board and Abu Dhabi Investment Authority.
