1000KW compressor on full load generates 300 l/s. Because so much energy is lost as heat during compression, 1KW of compressed air work costs 10Kw of electricity.
Manufacturing industry in the UK typically loses 30 to 40% of its compressed air to leaks.
An efficient plant may still accept around 10% after which it is uneconomical to improve further.
A 10mm hole e.g. a ruptured hose or broken air tool or one hundred 1mm holes across a plant will leak 124 l/s at a cost over £7,000 per annum (based on 1kWh = 2.7p)