Free Energy in Compressed Air | Green Energy News

November 7, 2009 – Vol.14 No.33

FREE ENERGY IN COMPRESSED AIR.
by Bruce Mulliken, Green Energy News

Energy innovations pop up in the least expected places.

Compressed air is far more useful than just for inflating tires. It’s used in repair shops and production facilities to run a variety of hand-held tools like sanders, grinders, impact wrenches, drills, caulking guns, nailers, paint spray guns, cutting tools, blow guns, and polishers. Chances are your friendly mechanic uses air powered tools to loosen and tighten bolts on your car. The body shop that fixed your dented fender used air tools to sand it smooth then paint it later. Homes – stick-built on site or modular from a factory – are nailed together with air powered nail guns and painted afterwards with compressed air, not a brush or roller.

And that’s just hand-held air powered (pneumatic) tools. In large manufacturing facilities air is used to move parts and components from one place to another, and compressed air is even used in robotics to position, machine, assemble and fasten components together to make finished products.

Compressed air has been stopping trains for well over a century and stopping trucks for decades, too. Inventor/industrialist George Westinghouse earned his initial wealth with his patented air brake system.

Motor Development International (MDI) is still planning to launch zero-emission cars powered by compressed air.

The compression of air and putting it to work is big business. Very big.

Compressed air is an energy storage medium. It takes energy to compress air but that energy is utilized later on in the work it does, like grinding out cavities in your teeth.

But now with a new product that seems obvious in hind sight, compressing air can be energy neutral – net zero – when the heat generated in compression is put to work.

Atlas Copco, a UK developer and provider of compressed air and gas equipment, generators, construction and mining equipment, industrial tools and assembly systems, is now launching its Carbon Zero line of oil-free air compressors. With advanced heat recovery systems the industrial compressors have been certified as recovering 100 per cent of the electrical energy input in the form of hot water at up to 90 degrees C (194 degrees F).

Atlas Copco's ZR 55-750 industrial grade compressors (rated from 55 to 750kW) are two-stage, oil-free, water-cooled units. Heat, that can be put to work, is captured at various points in the units. There is an intercooler between the first and second compressor stages, plus an aftercooler. There’s an oil cooler to grab heat from gearbox oil. But the interesting part is the extraction of heat from air as it’s compressed. Water jackets at both compressor stages do this job. The company describes the process:

“Because the ambient air input to the compressor contains moisture, this is condensed in the compression and cooling process, releasing latent heat (or condensation heat). This energy, transferred to the cooling water, results in the compressor generating both compressed air and hot water.”

At least 90 percent of the energy recovery (energy in the form of hot water) comes from capturing heat generated by the mechanical functions of the compressor. The rest of the heat captured comes from that latent source.

Obviously this is a compressor for situations where lots of pressurized air is needed and captured energy can be put to work in space heating or industrial processes. But the innovation shouldn’t be trivialized. Compressed air does considerable work in industries of all types. If a company can get compressed air with free-heat in the process, money is saved, energy consumption is reduced and emissions associated with making that heat previously are eliminated, then nearly everyone wins.

Links:

Atlas Copco
http://www.atlascopco.co.uk