Cost for motor/generators is not changing, but the tech is extremely mature. Costs for electrolysers and fuel cells are both falling fast. Air compression and l

Cost for motor/generators is not changing, but the tech is extremely mature. Costs for electrolysers and fuel cells are both falling fast. Air compression and liquidation are both mature technologies, but might respond to a massive increase in usage by getting cheaper. A survey of storage technology pilot projects show people doing much more expensive versions of each than will be deployed. The incentives for pilot projects favor over-complex systems based on over-complex processes described in papers that had to be that to get academic attention as novel, and grants likewise. When civil engineers get involved, systems will get radically simpler and cheaper. Probably designs will trade off efficiency, as the cost for a little extra power is much less than for complexity.