Also efficiency is largely irrelevant if system cost is low and we are talking about storing renewable energy. Pumped hydro is considered viable and it’s far less efficient than 70% but it uses already existing technology and can use existing infrastructure as well (pumping water uphill into a reservoir to later be put through an already existing hydro plant for example).
Yrrebnot t1_iwkdki1 wrote
Reply to comment by Josvan135 in Italian startup Energy Dome claims its CO2 grid storage batteries are cheaper than lithium-ion, and need no rare minerals, being made from just off-the-shelf steel components, water & CO2. It's opening its first 200 MWh facility in Sardinia in 2023 by lughnasadh
Also efficiency is largely irrelevant if system cost is low and we are talking about storing renewable energy. Pumped hydro is considered viable and it’s far less efficient than 70% but it uses already existing technology and can use existing infrastructure as well (pumping water uphill into a reservoir to later be put through an already existing hydro plant for example).