The South African mining industry is currently faced with a number of challenges. The increasing depth of mines, particularly gold mines, combined with constantly increasing energy charges, have presented problems when it comes to cooling the mine working area while maintaining energy efficiency. Says Russell Hattingh, Engineering Manager at Johnson Controls Systems & Service Africa, "Surface plants are commonly used in mines for bulk air cooling, which involves chilling the air above ground before sending it underground and distributing it in the ventilation network. It is also common practice to produce chilled water on surface and then send it underground for cooling purposes. However, while surface coolers are effective for shallower mines, as mining operations become deeper it becomes more viable to provide cooling closer to the working areas underground, since the cost of pumping, combined with thermal loss, becomes prohibitively expensive."