Most existing works using a displacement estimation method to estimate the CO2 emissions abated by wind energy are based on the current operating principles of the power system. They consider a fixed displacement emission factor since wind energy is assumed to replace high-carbon generation. This method may be unsuitable in the long run when the energy mix of most countries becomes more decarbonised. Consequently, wind energy would replace those technologies becoming increasingly predominant in the future, i.e. lower polluting fossil fuels such as natural gas and even other less competitive low-carbon technologies. In order to consider this effect, this paper proposes a new method that estimates a range of potential CO2 emissions abated by wind energy based on two dynamic displacement emission factors, which are periodically updated according to the evolution of the future energy mix. Such factors represent an upper and a lower limit of CO2 emissions avoided. The method is validated in the case study of the European Union over the period 2015-2050. The results show that the annual displacement emission factor by wind energy may vary from about 422 to 741 t CO2/GWh in 2015 to around 222-515 t CO2/GWh in 2050. The total CO2 abatement ranges from about 6600 to 13100 Mt CO2 in the period 2015-2050.
Keywords: CO2 emissions; Displacement emission factor; Environmental policies; PRIMES; Sustainability; Wind energy.