The funding covers the now-completed Getafe, Alcorcón, Olabeaga, Guarnizo, Martorell and Arenys del Mar reversible substations in the provinces of Madrid, Vizcaya, Cantabria and Barcelona. Adif AV is responsible for the implementation of electrification on both Spain’s conventional and high-speed networks.

The substations support the implementation of regenerative braking systems on Spain’s 3kV dc conventional network, and will help to reduce CO2 emissions equivalent to 2417 tonnes per year. This will generate estimated saving of around 10.45GWh per year (26%) and around €721,722 per year in energy costs.

The grant represents 27% of the €4.36m total cost of implementation for the substations. An additional €2.88m (66%) of funding was acquired through the sale of green bonds issued in 2018 and 2019 by Adif AV, with the remainder being funded by new green bonds launched in January.

The funding will be provided within the framework of IDAE’s Aid Programme for the implementation of energy saving measures in the railway sector, part of IDAE’s National Energy Efficiency Fund (FNEE). Under the framework, funding will be paid to Adif AV once energy savings have been justified in accordance with the framework benchmarks.

Adif has also requested funding under the programme for a further six substations in the provinces of Madrid and Barcelona, in Tres Cantos, Alcala de Henares, Pinto, Leganes, Granollers and Castellbisbal.

Unlike on ac lines such as on Adif AV’s high-speed network, in which regenerative braking systems are easily implemented with no additional infrastructure, dc systems used on the Adif conventional network require the implementation of inverters on traction substations along the route. The implementation of reversible substations equipped with inverters allows for surplus electricity generated by braking to be fully utilised by other trains on the network or be returned to the grid, rather than being dissipated.

The implementation of the new substations is a key part of Adif and Adif AV’s Plan to Combat Climate Change 2018-2030, and is intended to help the infrastructure manager achieve its goal of an 86% reduction in carbon emissions by 2030.