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ARES Performance

An ARES facility will provide the full range of energy storage capabilities generally associated with pumped-storage hydro at approximately 60% of the capital cost and at a significantly higher efficiency.  Additionally, ARES has system features which are not traditional to competing forms of energy storage, including but not limited to the following attributes:
Reactive Power Production – The shuttle-trains onboard Dual 3-Level Active Rectifier/Invertors are capable of supplying 25% of generated system power as reactive power for grid VAR support in full discharge mode and in excess of 100% of system power as reactive power while synchronized to the grid in standby.

Heavy Inertia – When in direct grid synchronization the ARES shuttle-trains provide beneficial heavy inertia -- augmenting grid stability against the loss of heavy generating facilities and increasing reliance on solar energy.

High Efficiency Regulation – While providing Regulation-Up and Regulation-Down support to the ISO a separate dedicated pool of loaded ARES shuttle-trains are available to dispatch from mid-system elevation complying with ISO regulation commands without having to overcome the efficiency loss of operating on pre-stored energy.  As such an ARES facility is able to perform a round-trip regulation Reg-Up/Reg-Down command at over an 80% operating efficiency.

Variable Output at Constant Efficiency – Unlike CAES and pumped-storage hydro there is no loss of system pressure during discharge.  ARES system efficiency is constant over the full range of discharge and power output. 


ARES rail based energy storage systems are covered by one or more of the following US patents: 8593012, 8674541 with foreign patents pending and issued.


Extensive site options
ARES sites are abundant in in the arid regions coincident with wind and solar resources maximizing transmission resources by providing storage at the point of intermittent generation.

ARES facilities are scalable from 100MW with 200MWh of storage capacity up to large 2-3GW regional energy storage system with 16-24GWh energy storage capacity.

No Use of Water

Lower Capital Cost
ARES cost is approximately 60% of an equivalent power pumped-hydro facility

Higher Efficiency
ARES round-trip energy storage efficiency is 78.3% – its round-trip Ancillary Services efficiency is 86%

Variable Output at a Constant Efficiency
An ARES system operates at a constant high-efficiency over its full range of power output.

Ancillary Services
ARES can provide the full range of Ancillary Services – Reg-Up, Reg-Down, Spinning Reserves, Black-Start as well as VAR Support andHeavy Inertia to the host electrical grid.

Lowest Levelized Cost kWh
Based on one full charge/discharge cycle per day, ARES has the lowest levelized cost per kWh of comparable technologies