Residual mix
Residual mix refers to a set of electricity for which the origin is not verified with a guarantee of origin.
Under the Directive of the European Parliament and Council on the Common Electricity Market (2009/72/EC), there is an obligation on electricity suppliers to provide invoices and marketing materials for end consumers that indicate the share of every energy source in the supplier’s total fuel mix for the previous year in a comprehensive, clear and nationally comparable manner.
On the basis of §3210 of the Energy Sector Organization Act, the transmission system operator is obliged to develop a method for the calculation of residual mix and, by 30 June, to publish the calculated quantities of residual mix for the previous calendar year. Residual mix refers to a set of electricity for which the origin is not verified with a certificate of origin.
In Estonia, in order to prove consumption of electricity is generated from renewable sources, certificates of origin are issued in Estonia or in the European Economic Area countries and thereafter cancelled in the electronic database managed by the transmission system operator to prove energy consumption in Estonia.
National residual mix allows calculation of the origin of electricity supplied by electricity retailers but not covered by certificates of origin, and makes the data comparable.
From June 2020, the official residual mix of Estonia has been calculated by Grexel Systems Ltd on behalf of AIB, assisted by Ostfoldforskning and Ecoinvent. More information regarding the calculation of the 2020 European attribute mix and the residual mix profiles of all the European countries can be found here on AIB website.
Estonian national residual mix 2014-2021
| Year | FOS | RES | NUC | |||
|---|---|---|---|---|---|---|
| 2014 | 89% | 7,223 TWh | 11% | 0,893 TWh | 0 | |
| 2015 | 88,37% | 7,127 TWh | 11,63% | 0,938 TWh | 0 | |
| 2016 | 93,17% | 7,634 TWh | 6,83% | 0,560 TWh | 0 | |
| 2017 | 100% | 8,976 TWh | 0% | 0 TWh | 0 | |
| 2018 | 100% | 8,503 TWh | 0% | 0 TWh | 0 | |
| 2019 | 81,79% | 6,73 TWh | 1,48% | 0,55 TWh | 16,73% | 1,38 TWh |
| 2020 | 69,47% | 5,4 TWh | 6,6% | 0,51 TWh | 23,93% | 1,86 TWh |
| 2021 | 76,37% | 5,83 TWh | 7,55% | 0,58 TWh | 16,08% | 1,23 TWh |
The CO2 content in Estonian residual mix 2021 was 636,58 gCO2/kWh and the radioactive waste content was 0,65 mg/kWh. The percentage of untracked consumption was 85,14% in 2021.
Terms used:
RES - electricity produced from renewable sources
FOS - electricity produced from fossil fuels
NUC - electricity produced from nuclear energy
Untracked % - The amount of national consumption that has not been covered with cancelled guarantees of origin or via another reliable certification system.