Compressed Air

Steam powered air compressor (at Walton Colliery). This magnificent machine was at one end of this colliery's power house. It was an inverted vertical compound steam engine with the steam cylinders direct coupled to two stage compressor cylinders below. It was built by Belliss & Morcom of Birmingham in 1922. The steam cylinders were 23" & 33" x 17" and it developed 715 indicated horsepower at 250 rpm. The steam pressure is thought to have been 150 psi. It was disused by 1977 and scrapped in 1982 following the closure of the colliery.

Compressed air is one of the basic utilities, next to water, electricity and gas. In some situations, it can replace these other utilities, providing flexibility (see product ecology, below). It could be generated by small wind installations which are mechanically coupled to air compressor. Alternatively, solar photovoltaic cells could power an electric air compressor, although this arrangement is likely more expensive.

Numerous uses for compressed air when we take back the economy

Applications and product ecology

Energy

• for energy storage (CAES, compressed air energy storage), see energy storage Wikipedia
• compressed air could be "co-fired" with biogas for electricity generation, saving gas
• pneumatic motors for all sorts of uses, replacing electric or hydraulic motors
• run power tools, examples here and also here
• generate compressed air via wind power (e.g. VAWT), directly powering an air compressor
• generate compressed air via (solar) heat engine that directly powers an air compressor

Transportation

• pneumatic transportation (see Treehugger article on FoodTubes)
• Compressed Air Water Pump

Biomass and Biomaterials

• drying of fuel biomass (... wood, manure, etc.) before further uses, such as combustion, pyrolysis
• drying and processing of (bio-)materials using Vortex Dehydration (also see: vortex dehydration and "Windhexe")

Food and Agriculture

• aeration of water in aquaculture and to make compost tea
• aeration of compost: so-called "Aerated Static Pile" (ASP) composting
• inflatable structures (greenhouses, tents, other temporary installations)
• cooling (possibly via vortex tube); for making Freeze Dried Fruit Powders
• various ventilation uses (e.g. air exchange in greenhouses, Passivhaus, underground mine, etc.), as an alternative to electric fans

Other

• using vortex tube for separation of atmospheric gases: yields nitrogen (for food preservation) and oxygen (to co-fire with gas and reach higher temperatures for metallurgical applications)
• control air flow in updraft and other gasifiers such as a TLUD
• various applications that benefit from having very hot flames (compressed air provides increased oxygen for hotter combustion)
• when precise temperature control from a flame is required

Links

• Wikipedia: "Compressed Air"
• Low-Tech Magazine: "Ditch the Batteries: Off-Grid Compressed Air Energy Storage"
• Wind Integrated Compressed Air Energy Storage In Colorado
• Windmill Driven Compressed Air
• Air Car (see: Wikipedia and Youtube)