Although Heat pumps are new to the South African market, it is a technology tested and used around the world to assist in the reduction of electricity usage and in this way reducing the amount of green house gasses being emitted into the atmosphere through the production of electricity using fossil fuels.

As part of Eskom’s Integrated Demand Management programme, they continuously look at ways to advise consumers, and set an example to contribute to the reduction of energy usage in South Africa. Three industrial heat pumps, supplied by Tasol, 2 x 9.2kW (input) and 1 x 4.6kW (input), were recently installed at the Eskom site in Germiston. The hot water reticulation network is supplied by 2 x 2000 litre tanks with 24kW of heating capacity each and 1 x 2500 litre tank with 24kW heating capacity. The installation of the heat pump units were combined with the replacement of two hot water cylinders. Air source heat pumps work on the reverse refrigeration cycle principle.

The thermal heating capacity is typically achieved in a ratio of 1 to 4 i.e. for each 1kW (electrical energy from the Eskom grid), 4 kW of thermal energy is generated. This ultimately results in a reduction of energy consumption as well as a demand reduction on the Eskom grid network. Mr.Hannes van der Merwe from Eskom says that electricalsavings were seen with immediate effect since the installation of the Tasol heat pumps. Typically, the demand profile is reduced from 48kW to less than 15kW. The expected energy savings are currently being measured and verified, but all indications are that acceptable savings will be achieved.

“Heat pumps are a technology that is getting more popular these days and is a good alternative to consider for reducing electricity usage”, says Tasol’s Managing Director, Mr. Chris Nelson. “Energy efficiencies reached by using heat pumps to heat water can be as much as 70 percent. However, by combining heat pumps with a technology such as solar water heating systems (a free energy source), forming a Hybrid system, electrical savings on water heating can be maximized up to 90 percent in some cases. This is indicated through tests done at our Energy test centre at the NMMU in Port Elizabeth,” Nelson adds.

The market for solar and other alternative energy solutions is expected to increase vastly within the next few years, due to the higher energy demand alongside the shortage of electricity capacity projected by economists for South Africa in the next 20 years.