There have been several compressor houses on the Geevor site in the past.
By 1917, compressors were installed at Wethered Shaft. In 1920, a combined winding engine and compressor house with boiler house and fuel store was constructed next to Victory Shaft, which was then being sunk. From 1952 until 1953 a new compressor house was constructed where you can see it today. The compressor house, holds three large machines which supplied compressed air to power various tools around the mine. Most of the compressed air was piped underground to power drills, rocker shovels, winches and ventilation fans.
The compressors are two-stage and electrically powered. Together they could produce 110 cubic metres of air per minute at a pressure of 6 atmospheres (6 x normal atmospheric pressure). The air was piped to storage tanks outside the building and then underground via a network of steel pipes. The drills were connected to these pipes by flexible hoses and could be more than a kilometre from the compressor and 600 metres below the surface.
Air can be compressed like a spring to store energy. It is distributed underground at high pressure through pipelines and valves to power drills, and machinery. Compressed air is safe but not as efficient as electricity. There are many advantages to using air power. Air drills are rugged, reliable and safe to use in wet conditions. Air pipes are easy to extend and repair and the air exhausted from the drills helps to ventilate the mine.