"Storing energy by suspending weights in disused mine shafts could be cheaper than batteries for balancing the grid, new research has found.
According to a report by analysts at Imperial College London and seen by BusinessGreen, gravity-fed energy storage systems can provide frequency response at a cost cheaper than most other storage solutions."
"According to the paper, gravity-fed storage providing frequency response costs $141 per kW, compared to $154 for a lithium-ion battery, $187 for lead acid batteries and $312 for flywheel.
The numbers assume the storage performs 700 cycles per year of 15 minutes each, at a power output of 4MW, to help manage the real time grid balance between system demand and total generation."
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