Residual mix
The residual mix represents the quantity of electricity the origin of which is not proven by guarantees of origin.
For electricity consumers
The origin of the electricity consumed is proven by the use of a guarantees of origin.
Guarantees of origin for renewable energy can be obtained together with electricity, i.e. by choosing a suitable so-called green package from an electricity supplier. Another option is to procure them separately from electricity, i.e. procure so-called conventional electricity and, subsequently, obtain the required number of guarantees of origin to prove the origin of electricity.
If guarantees of origin have not been used, the origin of electricity is Estonian residual mix and its specific CO2 emissions per kWh are published in the table below.
Residual mix 2019–2023
Year |
Proportion of type of energy in residual mix |
CO2 (g/kWh) |
Radioactive waste (mg/kWh) |
Proportion of electricity of unverified origin |
||
---|---|---|---|---|---|---|
Renewable (RES) |
Fossil (FOS) |
Nuclear (NUC) |
||||
2019 | 1,48% | 81,79% | 16,73% | 757,71 | 0,51 | 95,09% |
2020 | 6,60% | 69,47% | 23,93% | 546,89 | 0,88 | 89,91% |
2021 | 7,55% | 76,37% | 16,08% | 636,58 | 0,65 | 85,14% |
2022 | 7,22% | 83,11% | 9,67% | 715,18 | 0,36 | 84,10% |
2023 | 6,16% | 87,13% | 6,71% | 711,66 | 0,23 | 79,11% |
In 2023, the share of electricity consumption in Estonia not covered by guarantees of origin is 79.11%, the CO2 content of residual mix is 711.66 gCO2 /kWh, and the content of radioactive waste is 0.23 mg/kWh.
Background
Pursuant to subsection 3210 (9) of the Energy Sector Organisation Act, the system operator is obligated to develop a methodology for calculating the residual mix and publish the residual mix calculated for the previous calendar year by 30 June. The residual mix represents the quantity of electricity the origin of which is not proven to consumers by guarantees of origin.
Guarantees of origin issued in Estonia or the European Economic Area and subsequently deleted from the system operator’s electronic database to prove the origin of energy consumed in Estonia are considered valid guarantees of origin for the purpose of proving the consumption of electricity from renewable sources in Estonia.
The national residual mix allows for the calculation of the origin of electricity supplied by electricity suppliers but not covered by guarantees of origin and makes the data provided comparable.
Since June 2020, Estonia’s official residual mix has been a residual mix calculated and approved on the order of the AIB (Association of Issuing Bodies, of which Elering has been a full member since 2014). More information about the methodology and calculation process used is available on the AIB website. The following graph shows the content of Estonia’s residual mix in comparison with other European countries. Source: AIB

Explanations of terms and abbreviations:
RES – Electricity produced from renewable energy
FOS – Electricity produced from fossil fuels
NUC – Electricity produced from nuclear fuels
Untracked % – The proportion of electricity consumption the origin of which is not proven by guarantees of origin or in any other reliable manner