Johannesburg – State-owned power utility Eskom is looking to solar water heating to relieve pressure on its overloaded power grid.

On Wednesday, Eskom published an advertisement in the business section of The Star newspaper, in which it asked for proposals to investigate possible funding sources and strategies for its solar water heating project.

The programme, which takes the form of an incentive scheme, is one of many Eskom is implementing in the residential sector.

At present, the residential sector in SA consumes 17% of the country’s electricity. This is according to the Community for Energy Environment & Development (Commend), which says solar water heating may reduce energy consumption by “more than half”.

Eskom wants to conduct a feasibility study on solar water heating “as a result of the increased demand for electricity in SA”, in an attempt to meet the renewable energy target set by government in 2008.

Government has set a target for renewable energy to contribute 10 000 gigawatt hours (GWh) of final energy consumption by 2013.

In the US, 10 000MW in generating capacity produce enough electricity to power the equivalent of over 2.5m homes, so 10 000GWh would produce capacity to power over 2.5bn homes. This would be consistent with 2.5m homes using an average of 4 000 watts over time.

The department of minerals and energy estimate a power rating of 1300MW of installed capacity required in order to produce the 10  000GWh by 2013. Thus, assuming South African homes use as much as American homes , the SA target would supply (2.5m x 1 300MW/10 000MW) 325 000 homes.

Obtaining a large portion of the 10 000GWh from solar water heating would be the most cost-effective and easiest renewable option to implement, according to Eskom. “Solar water heating could contribute up to 23% of this target,” it said.

With SA enjoying more sunshine than most other countries and a radiation intensity almost twice that of Europe, solar water heating is “by far” the most cost-effective renewable technology which could be introduced, according to Eskom. There are cost benefits too.

“The cost per kilowatt (kW), which is 1 000 watts, could easily be as low as R22 500 per kW compared to other renewable technologies which could be as much as R100 000 per kW,” it said.

If Eskom develops solar water heating into a large-scale project, it could take a lot of pressure off the national power grid.

In 2008, the state-owned power utility was haunted by supply constraints and had to force blackouts on the country, which led to losses across many industries.

Article by Nicole Rego, courtesy of Fin24 website