- 20 Apr 2018
FOI reference: FOI/18/01101
Date received: 25 March 2018
Date responded: 17 April 2018
For clarification and avoidance of doubt, I should be grateful for answers to the following questions:
1. Currently missing is any information on the variations in total electricity demand in Scotland on a daily or weekly basis to include the various generation components (gas, nuclear, hydro, wind etc). Why then, together with the contribution to meeting this demand from the various fuel sources (gas, nuclear, coal, wind, transmission, etc., on a daily or weekly basis, is this information available to neither professional bodies nor the public?
2. What are the calculated additional CO2 emissions from fossil fuel generators when they are required to cycle up and down to match wind variations, and meet required demand?
1. The Scottish Government does not hold data on the variations in total electricity demand in Scotland on a daily or weekly basis to include the various generation components (gas, nuclear, hydro, wind etc.). This data is held by National Grid, who is responsible for operating the electricity system across Great Britain. They publish real-time GB demand data on their website (see https://www.nationalgrid.com/uk/electricity/market-operations-and-data) and they release information on the generation mix across GB on a daily basis.
2. Information which outlines that emissions from fossil fuel generators are higher than those of renewable generators can be found at the following sources:
a. BEIS: Table 5D shows that emissions from 'All Fuels' (which include renewables and nuclear) is lower than that of all of the fossil fuel categories. https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/633779/Chapter_5.pdf
b. BEIS: Fuel mix disclosure table (number 3), shows CO2 emissions by generation source. Renewables is zero, whilst other sources are significantly higher. https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/641983/Fuelmixdisclosurewebpage2017.pdf
c. CXC: this looks at life cycle emissions, taking into account emissions associated with development and construction of generation assets as well as generation https://www.climatexchange.org.uk/research/projects/assessing-the-life-cycle-costs-and-carbon-emissions-of-wind-power/ (figures 18 and 19 from the main reports compare carbon emissions from offshore and onshore wind with those of other types of generation)
In source c (above) – there is discussion/coverage of the point that although the inclusion of intermittent generation as part of the overall mix causes traditional thermal generators to operate slightly less efficiently, due to them having to cycle up and down in response to the intermittency, the overall impact is still such that emissions fall due to the inclusion of renewables. Overall, wind generation reduces emissions, as it is displacing other more emissions-intensive methods of electricity generation, such as coal or gas generation.
Finally, in terms of measurement, we are required under EU regulation and the Climate Change Act (Scotland), 2009 to report on emissions across the whole economy, through the Greenhouse Gas Inventory, and for major emitters through the EU ETS scheme (for which SEPA collects emissions data).
The Scottish Government is committed to publishing all information released in response to Freedom of Information requests. View all FOI responses at http://www.gov.scot/foi-responses
Please quote the FOI reference
Central Enquiry Unit
Phone: 0300 244 4000
The Scottish Government
St Andrew's House