Young David L, Johnston Henry, Augustine Chad
National Renewable Energy Laboratory, Golden, CO 80401, USA.
iScience. 2021 Nov 17;24(12):103459. doi: 10.1016/j.isci.2021.103459. eCollection 2021 Dec 17.
Renewable forms of electricity generation like solar and wind require low-cost energy storage solutions to meet climate change deployment goals. Here, we explore the use of depleted hydraulically fractured ("fracked") oil and gas wells to store electrical energy in the form of compressed natural gas to be released to spin an expander/generator when electrical demand is high. Our reservoir model indicates that the same dual-porosity geological environment of fracked wells used to liberate hydrocarbons is also suitable for storing and releasing gas in a diurnal or seasonal cycle. Round-trip storage efficiency is calculated to be 40%-70% depending on the natural reservoir temperature. Levelized cost of storage is estimated to be $70-270/MWh, on par with pumped hydro storage. This study indicates that repurposed "fracked" wells could provide a much-needed low-cost seasonal energy storage solution at the TWh scale.
太阳能和风能等可再生发电形式需要低成本的储能解决方案，以实现应对气候变化的部署目标。在此，我们探索利用枯竭的水力压裂（“压裂”）油气井，将电能以压缩天然气的形式储存起来，在电力需求高时释放出来，带动膨胀机/发电机运转。我们的储层模型表明，用于开采碳氢化合物的压裂井的双孔隙地质环境同样适用于以昼夜或季节循环的方式储存和释放气体。根据天然储层温度，往返存储效率计算为40%-70%。储能平准化成本估计为70-270美元/兆瓦时，与抽水蓄能相当。这项研究表明，经过重新利用的“压裂”井能够在太瓦规模上提供急需的低成本季节性储能解决方案。
