Compressed Air Energy Storage

Energy Storage  *  Engineering  *  Frequency Regulation

Compressed Air Energy Storage

What is Compressed Air Energy Storage?

Compressed Air Energy Storage is one of the emerging "Bulk Energy Storage" technologies for storing energy - typically the energy is generated and stored during off-peak periods, and dispatched to the electric grid during peak demand times. 

One Bulk Energy Storage method is Compressed Air Energy Storage - since the wind doesn't always provide enough energy for wind turbine generators to generate electricity, will store the wind energy when they generate power and "off-peak electricity" to pressurize and store air underground.  The air can be used later, by releasing it to drive generators. 

The problem with wind energy - particularly in Texas and the wind belt, much of the wind power is generated at night-time, when the power isn't as valuable.  "Dispatchable Wind" power becomes a reality with Compressed Air Energy Storage - making wind energy available in real time, or "saved" for later when power is needed.

The Department of Energy (DOE) is presently working with several states to build Compressed Air Energy Storage parks, which would integrate a 75- to 150-megawatt (MW) wind farms, that are integrated with the Compressed Air Energy Storage parks.   

Before a Compressed Air Energy Storage can be used, the underground caverns that store the wind energy, must be of the right geological size, depth formation and cap rock structure.


CAES Diagram courtesy Dept of Energy


Compressed Air Energy Storage facilities will operate on off-peak electricity during nighttime hours. They will use the output from nearby wind power plants to operate when overall demand on the power grid is low and the utility dispatcher has curtailed output from the wind power plant. During the energy storage cycle, a compressor pushes air into the porous rock that may be several thousand feet underground and beneath the layers of impermeable cap rock. When demand for electricity rises, the stored air will be released, heated, and used to drive electric generators.


Diagram Courtesy: Imperial College

Compressed Air Energy Storage
has been in use for more than 20 years in demonstration projects, and two facilities — one at 290 MW in Huntorf, Germany that began operations in 1978, and another in Alabama, that began operating in 1991. The Compressed Air Energy Storage facility in Alabama is rated at 100 MW.


Clean Power Generation

Running on "green fuel" such as Biomethane, B100 Biodiesel, Synthesis Gas or natural gas, our CHP Systems are the greenest "clean power generation" systems available.

With Natural Gas at approximately $4.00/mmbtu, our Clean Power CHP Systems  generate power for about $0.04 / kWh (fuel cost).

With operations & maintenance added, that's  about 5.5 cents /kWh - or approximately 50% - 60% less than what most commercial customers are paying, on average, for their electricity.

CHP Systems
(Cogeneration and Trigeneration) Plants 
Have Very  High Efficiencies, Low Fuel Costs & Low Emissions

The CHP System below is rated at 900 kW with a 
heat rate of 4100 btu/kW & system efficiency of 92%.

The CHP System below features: (2) Natural Gas Engines @ 450 kW each 
on one skid with optional Selective Catalytic Reduction system 
which removes Nitrogen Oxides to "non-detect."



A CHP System may be the best solution for your company's economic and environmental  sustainability as we "upgrade" natural gas to clean power with our clean power generation solutions.  CHP Systems and Dispersed Generation power plants are an ideal solution for data centers, district energy systems electric utilities, electric co-ops, electrical sub-stations, energy service companies, food processing plants, hospitals, military bases and  universities among many others. 

High-efficiency CHP Systems eliminate blackouts, electric grid supply problems and significantly reduce greenhouse gas emissions and hazardous air pollutants associated with electric power generation at central power plants.  Our emissions abatement solutions reduce nitrogen oxides (NOx) to "non-detect" and can be installed and operated in most EPA non-attainment regions!


Compressed Air Energy Storage - CAES

Bulk Energy Storage  *  Dispatchable Wind  *  Frequency Regulation  Peak Shifting  *  Salt Dome Storage








"Bulk energy storage is truly one of the most promising new areas of the electricity industry. The Energy Storage Council believes that bulk energy storage will become the "sixth dimension" of the electricity value chain following fuels/energy sources, generation, transmission, delivery, and customer energy services."

For more information on Bulk Energy Storage, visit: 

What is Pumped Hydro Storage?

Pumped hydro storage is a method of storing energy that is generated when the price of electric power is low - and used at a time when the price of power is high. Pumped hydro storage - acts as a battery of sorts, with the ability to deliver electricity on demand. 

Pumped hydro storage works by pumping water from a reservoir that is located at a lower elevation - to a reservoir that is located at a higher elevation - and during the period of time electricity usage is low as well as the price of selling electricity. When the power demand peaks, so does the price of electricity but this also happens to coincide when wind power is not available.  This is when the water that was pumped up to the higher elevation reservoir is released, power is generated from the hydroelectric power plant, and the electricity is then released to the electric grid.


Battery Energy Storage  *  Bulk Energy Storage  *  Demand Side Management  *  Dispatchable Wind 

Distributed Energy Resources  Frequency Regulation  *  Flywheel Energy Storage  *  Load Leveling 

  Molten Salt Storage Peak Shifting  *  Salt Dome Storage  Waste Heat Recovery


"Net Zero Energy" to Become $1.3 Trillion/year Industry by 2035


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~ R. James Woolsey, Jr., former Director of the CIA

Price of Addiction
to Foreign Oil

According to R. James Woolsey, for Director of the Central Intelligence Agency, “The basic insight is to realize that global warming, the geopolitics of oil, and warfare in the Persian Gulf are not separate problems — they are aspects of a single problem, the West’s dependence on oil.”  


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Compressed Air Energy Storage - CAES

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