COMPRESSED AIR ENERGY STORAGE – FURTHER ALONG

With the growing momentum of big New Energy installations, the hunt is on for the most economic means of storage.

One of the first and best options: Compressed Air Energy Storage (CAES).

The basic idea has been seducing engineers and dreamers since at least the 1970s: Intermittent sources of energy like wind and sun drive compressors to pressurize air in arrays of pipes and tanks or vast underground caves. The air is subsequently released in a steady, predictable stream to meet energy demands in exactly the same way any other power plant steadily, predictably generates energy.

Example: Wind often is strongest at night, when demand is lowest. Some night winds could be used to run the grid while excesses could be stored and released to supplement other grid supplies during the working day’s peak demand.

Stephen C. Byrd, president, P.S.E.G. Energy Holdings: “This is a game-changing technology…There is a desire for energy independence, and this will reduce the need for oil and natural gas.”

Yes, it will change the game and reduce fossil fuel dependence - when it is done efficiently and cost effectively. Previous attempts have proved the technology but not met cost and efficiency requirements.

Important stipulation: Wind energy’s intermittency issues are readily skirted by the fact that it is predictable. Where the wind is expected to drop off, power providers can integrate grid supply from other locations where the wind is blowing (or from other power sources).

Currently, almost all the wind energy-generated electricity produced is fed into the gird and consumed. In fact, the U.S. Department of Energy study affirming the practicality of the wind industry's plan to provide 20% of U.S. electricity by 2030 indicated there is no need for storage to do so.

Robert E. Gramlich, policy director, American Wind Energy Association (AWEA): “…we don’t want to give anyone the impression that storage is needed to integrate wind. Even growing 20-fold, storage isn’t needed.”

New technology may make the CAES concept, tried in various configurations since the 1970s, more workable. Utilities are interested.

The most affordable use of CAES would be where large wind (or solar) installations are in the vicinity of existing unused mines, oil & gas wells, caverns or reservoirs. In such cases, dthe cost of building storage would not be as great.

An underground reservoir the size of a pro football stadium could hold 900-megawatts of compressed air energy. It would take 8 hours to fill and could release power for 8 hours.

There are 2 “best uses” of storage: (1) For wind, it reduces the need even further for baseload supplementation by fossil fuels or nuclear, and (2) for solar, it offers the ideal solution for night generation.

It is unlikely there will be enough infrastructure built in the immediate future to urgently necessitate either. The 2020s, however, are not that far off. And remember what Laura always says. Nevermind who Laura is. Just remember what she says: Prior planning precludes poor performance.

Arshad Mansoor, vice president/power delivery and utilization, Electric Power Research Institute: “In the next couple of years, we want to install a couple of them so it becomes a tool in the toolbox to meet needs…”

Excellent PowerPoint presentation on CAES

Robert Rapier’s assessment of CAES

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Air Storage Is Explored For Energy
Ken Belson, August 26, 2008 (NY Times)

WHO
Public Service Enterprise Group Global LLC (PSEG Global), a subsidiary of P.S.E.G. Energy Holdings; Michael Nakhamkin; Energy Storage and Power (Roy Daniel, chief executive)

WHAT
Energy Storage and Power, a joint venture of Nakamkin and PSEG Global, will develop and promote a Compressed Air Energy Storage (CAES) technology.

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WHEN
- The CAES concept is decades old but has never been perfected at a competitive cost.
- 1970s: A CAES plant was developed in Germany.
- 1991: A CAES plant was developed in Alabama.
- P.S.E.G. Energy Holdings will invest $20 million over three years in the new CAES project.

WHERE
- The joint venture will be based in New Jersey.
- P.S.E.G. Global wants to build a wind installation off the New Jersey coast.
- Compressed air storage could be in pipelines, tanks or underground caverns.
- A reservoir is typically about 1500 feet underground.

WHY
- A CAES storage option could be added to the planned P.S.E.G. Global offshore installation.
- The offshore installation would have 95 turbines and a 350 megawatt capacity.
- P.S.E.G. Global is sister company to Public Service Electric and Gas Company, New Jersey’s largest power distributor.
- Nakhamkin worked on the plant in Alabama.
- Improvements in this generation of CAES technology: (1) reduced generator startup time, cutting compressed air consumption and emissions; (2) more standard components, potentially cutting building costs.
- New Jersey storage would likely be in tanks and pipelines because the state’s solid rock ground would make digging caverns expensive.
- Upstate NY offers depleted salt carverns in the vicinity of wind installations.
- With enough of a CAES infrastructure, New Energy-generated electricity could become a commodity sold across the grid nationally.

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QUOTES
- Robert E. Gramlich, policy director, American Wind Energy Association (AWEA): “Different sectors like to associate with wind power, and if compressed air will truly help wind, then fine…”
- Laura: “Prior planning precludes poor performance.”