The UK 's National Grid has revealed the de - rating process for solar and wind , for participation in the Capacity Assessment and the proposed methodologies . Greater levels of data regarding “ long run average contribution ” of weather resources enabled the National Grid to update its notional power curves for onshore and offshore wind for the first time in several years . Wind was given a de - rating of 8.2 % to 9 % , and offshore between 12 and 14.6 % . However , a paucity of data for solar saw it given a de - rating of 1 % to 2 % , boosted from " almost negligible " by the development of storage technology .
The UK's National Grid has revealed the de-rating factors for solar and wind energy for participation in the Capacity Market and the proposed methodologies. Greater levels of data regarding “long run average contribution” of weather resources enabled the National Grid to update its notional power curves for onshore and offshore wind for the first time in several years. Onshore was given a de-rating of 8.2% to 9%, and offshore between 12.1 and 14.6%. However, a paucity of data for solar saw it given a de-rating of 1% to 2%, boosted from "almost negligible" by the use of storage technology.