The recovery of heat from high tension cables using heat pumps

Rook Services has developed a new approach to the problem of cooling sub-surface high tension cables. Using our knowledge of ground source heat pumps, we have produced a system for the recovery of the heat generated by the cables under load. This wasted heat is extracted and concentrated using a heat pump which can then be used to heat homes, offices, schools, swimming pools etc.

The target operating temperature of cables is between ambient and 40°C, but at times of high load temperatures up to 90°C are experienced, and in extreme conditions this can rise to 120°C. At these temperatures cable expansion and contraction, become a major issue reducing the cables operating life and effecting joint integrity. To prevent damage, the cables carrying capacity is down rated and the cable may be taken out of use. This creates problems for the grid operators at times of high demand, re-routing supplies and re-balancing loads across the network. Attempts have been made by the network operators to cool the cables using conventional cooling techniques, such as installing water pipes adjacent to the cables but these have met with limited success.

We have a dedicated website for this service which is over at: