Emissions from the Spanish electricity system have fallen by 30 million tons in the last 5 years

The data is from Red Eléctrica de España, which has just published the report “_CO2 emissions associated with electricity generation in Spain”, which details the methodology for calculating greenhouse gas emissions derived from the sector. Also in the last 5 years, the emission factor has decreased by 30%, from 0.26 tons of ceodós equivalent per megawatt hour generated (tCO2-eq/MWh) in 2015 to a factor of 0.19 tCO2-eq/MWh reached last year.

The greenhouse gases (GHG) considered by the IPCC (Intergovernmental Panel on Climate Change) and by the Spanish Emissions Inventory System (SEI) are CO2, CH4, N2O and compounds derived from Fluoride or fluorinated gases (F-gases such as SF6). GHG emissions due to electricity generation are mostly due to gases formed in combustion, so for these purposes, _{CO2 and N2O} emissions are taken into account. In order to calculate the greenhouse effect potential of N2O, the GWP (Global Warming Potential) value collected in the Fifth Assessment Report (AR5) of the IPCC (intergovernmental panel on climate change) is used, which assigns N2O a GWP of 265, which means that 1 gram of N2O has a global warming potential equivalent to 265 grams of CO₂ .

According to the report just published by Red Eléctrica de España, GHG emissions at the national level are estimated for 2018 at 334.3 million tonnes of ceodós equivalent (MtCO2-eq). Electricity generation accounts for 18% of GHG emissions, compared to 27% of transport or 20% of industry. These values refer to CO2-eq, and include both _CO2 emissions and those of other GHGs (N2O, CH4 and fluorinated gases). In the case of the Spanish electricity system, explains REE in its report, emissions have been reducing “as a result of the higher rate of renewable energies and the reduction of production with coal, going from about 80 MtCO2-eq in 2015, to approximately 50 MtCO2-eq in 2019”. The emission factor has gone from 0.29 tCO2-eq/MWh in 2015 to 0.19 tCO2-eq/MWh in 2019 (i.e. -30%).

How REE calculates

These CO2-eq emissions are calculated from emission factors expressed in tCO2-eq per MWh of electricity produced, grouped according to the different territories and generation technologies. These emission factors allow to obtain the total tons of CO2-eq emitted by a generator or grouping, multiplying the emission factor assigned by the energy produced (MWh) by the generator or grouping. “In this way,” they explain from REE, “we can calculate the total CO2-eq emissions associated with the generation of electricity in our electricity system.” Emission factors are generally updated on an annual basis. Additionally, updates are made to them whenever there are circumstances that require it.

Emission factors take into account only direct emissions associated with electricity production and do not include indirect emissions associated with the construction of generation plants, fuel transport, maintenance, etc.

Source: Renewable Energies