Power firm British Energy today announced plans to extend the life of two of the UK's nuclear power stations for a further five years.
The Hartlepool and Heysham 1 plants have been dogged by output issues in recent years but British Energy (BE), owned by French company EDF Energy, said the reactors had passed a technical and economic evaluation.
BE, which has eight nuclear power stations in the UK, said the move to extend the lives of the power stations had secured around 700 jobs on each site.
The announcement comes a day after the Government approved electricity market reforms which are expected to encourage investment in low-carbon power generation.
BE took four reactors at Heysham 1, near Morecambe, in Lancashire, and Hartlepool, in County Durham, out of service in October 2007.
The move came after it discovered wire corrosion on one of the boiler closure units, which form part of each reactor during a maintenance inspection.
The programme of repairs was completed last year but the reactors have since been running at reduced capacity.
The firm decided to extend the lives of the two power stations when a solution was found to boost output close to full load - but it will need to be implemented during outages over the next few years.
Heysham 1 and Hartlepool are both capable of supplying more than 1.5 million homes each - enough electricity to keep three cities the size of Liverpool supplied during peak loading hours.
A spokeswoman for EDF Energy said: "Extending the lives of its nuclear plants has remained a strategic priority for EDF Energy since coming together with British Energy almost two years ago.
"So it's particularly good news to be able to announce the decision to extend the operating lives of these two stations which started generating in the early 80s.
"Life extension is an important way of bridging the generation gap in the UK without risking carbon reduction targets."
Alongside Heysham 1 and 2 and Hartlepool, its sites include Dungeness B in Kent, Hinkley Point B in Somerset, Hunterston B in Ayrshire, Sizewell B in Suffolk and Torness in East Lothian.
Energy Secretary Chris Huhne yesterday set out a four-pronged approach to ensure that investment goes into low-carbon energy from renewables, nuclear and cleaner fossil fuels, and to encourage new providers to enter a market currently dominated by six big companies.