LONDON, Oct 14 (Reuters) - Britain will have a surplus power margin of 6.6 percent this winter over what is needed to meet electricity demand, National Grid said on Friday.
The so called de-rated margin is higher than July's forecast for this winter of 5.5 percent.
National Grid said it included 3.5 gigawatts (GW) of back-up power services it has procured.
"Additional generation capacity at Eggborough power station has returned to the market and an outage on the East West Interconnector has decreased exports to Ireland," National Grid said in its winter outlook report for 2016/17.
"These events have had a positive impact on the outlook for the winter," it added.
Reporting by Nina Chestney and Susanna Twidale; Editing by David Goodman