U.S. Startups Use Fracking Tech to Store Clean Energy

U.S. startups are developing proprietary technologies based on hydraulic fracturing to drill wells for storing renewable energy from solar and wind in underground pressurized water reservoirs.   As the share of renewable energy in electricity generation in the top American oil state, Texas, grows - so does the need for energy storage, which ensures clean energy is available when needed.  The new pressurized storage technology could be an alternative to lithium-ion batteries if it proves commercially feasible and cost-effective in…