This page provides information on the GB electricity data files available from the National Grid (NG). The NG calls these files “demand data”, but they contain much more than just demand. First of all I define the key terminology used in this blog, and how it relates to NG data.
“Consumption” means the total usage of electricity, some of which is generated locally by “distributed” generators, and the remainder is generated by “metered” generators or by import via interconnectors.
“Distributed” generators reduce the “demand” made on “metered” generators:
demand = consumption – distributed-generation
One particular type of distributed generator is “embedded wind”, so:
distributed-generation = embedded-wind + other-distributed-generation
“Residual Consumption” = consumption – other-distributed-generation
= demand + embedded-wind
NG Demand Data Files
The NG files contain the following information at 30-minute resolution, with some of the data being present back to 2005 (ND = National demand, TSD = Transmission System Demand):
ND, I014_ND, TSD, I014_TSD, ENGLAND_WALES_DEMAND
NON_BM_STOR, PUMP_STORAGE_PUMPING, I014_PUMP_STORAGE_PUMPING
Residual Consumption Data
The following figure shows daily winter (December to February) peak Transmission System Residual Consumption (and Estimated Embedded Wind Power at peak demand time) from winter 2005/06, a very important set of data for determining how much electricity capacity is needed to meet future demand:
Embedded Wind Generation
National Grid estimates of embedded (non-metered, mostly single turbine and small farm) wind generation in MW are available from 28th October 2007. I use this data to estimate how much METERED wind power would be produced TODAY from the weather patterns in the past, back to 28th October 2007. The accuracy of this estimation can be assessed from the following figure, in which a manually scaled version of estimated embedded wind power is compared with metered wind power data downloaded from the gridwatch website, for winter 2011/12, at 18:00 hours on each day (close to peak demand time):
In effect, the NG estimates of embedded wind generation are estimates of a wind power related average wind speed over GB at wind turbine heights, and this can be used to estimate with reasonable accuracy the generation from the other set of wind turbines, the set that are metered by NG.