ENTSOG TYNDP 2017 - Main Report

7.3 Storage and Transmission

7.3.1 ENERGY STORAGE

Gas infrastructure offers both flexible short term and seasonal long term storage potential, both in the capacity and capability of the pipeline network itself, plus the specific storage infrastructure connected to the network which includes onshore cavern systems, onshore and offshore depleted fields and LNG storage facilities. As previously mentioned, this has largely been developed in order to cope with the sea- sonal and operational demand variations driven by the current needs, but also has potential in years to come. When considering the requirements of the future energy system, the use of intermit- tent renewables and the growing share of solar but especially wind in the power sec- tor, means that it will become more challenging for electricity grid operators to balance the system. Hydro generation, demand side frequency response and bat- tery technology are all potential solutions for short term frequency issues, with most focus on the latter two due to limited possibilities for hydropower sites and potential- ly high environmental impacts from land use and conversion. Current developments for battery storage technology are progressing as short term energy solutions  1) . European decarbonisation may lead to an electrification of the heating sector, where the challenges of seasonal variations in demand are far greater. Current UGS working gas volumes are over 1,200,000GWh, with a maximum with- drawal capacity of over 20,000GWh/d. Even during the mild winter of 2015/16 UGS provided over 10,000GWh of gas on the peak day. This is approximately the same value of energy required on the peak day for the electricity transmission system in 2015. The seasonal and peak requirements of gas storage infrastructure could change as the energy system transitions, with greater energy efficiency and increased electrifi- cation of some sectors. However, gas infrastructure offers vast seasonal or annual energy storage, which when combined with renewable gases offer a long term low carbon solution that utilises infrastructure that is already in place.

 1) In the USA, the Southern California Edison battery project that is linked to a wind power generation site will provide 400 MWh (100 MW for 4 hours). Also South Korea plans to build the largest battery-based energy storage systems (BESS) in the world representing 500 MWh in 2017 – http://energystoragemedia.com/worlds-largest-frequency-regulation-bat- tery-energy-storage-system-installed-in-south-korea/battery-energy-storage-system-installed-in-south-korea/

Ten-Year Network Development Plan 2017 Main Report |

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