What is the role of an accumulator in energy recovery systems?

 An accumulator's role in an energy recovery system is to capture hydraulic energy that would otherwise be wasted as heat, store it as pressurized fluid against a compressed gas, and return it on demand to power the next work cycle. By smoothing out peaks and absorbing braking or lowering energy, accumulators cut fuel and electricity use, allow smaller pumps and prime movers, and reduce heat load across the system. 

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