Companies need to consider more renewable-energy sources to deal with the electricity shortage challenge that the country is facing. Of all the renewable energies, geothermal energy provides an attractive alternative.
“We will be presenting a paper on geothermal energy and its applications for the country at this year’s Energy Indaba, particularly how it can assist in alleviating the energy crisis in the country,” says Greenstone Geothermal chairperson Mohamed Madhi.
The untapped opportunities that geothermal energy can provide will also be highlighted to stakeholders and government.
“With deep geothermal energy, the ground is drilled to about 4 km below the surface and water is pumped in through an injection well to harvest the heat from the rocks. The high temperatures heat the water, which can be used to drive specialised turbines to generate electricity,” he explains.
“Geothermal power provides enough energy for most companies’ and communities’ energy needs. “Heat has been generated from deep within the earth for millions of years and we are only beginning to understand the vastness of the resource. There is enough heat in the earth to cater for a large proportion of South Africa’s energy needs,” he adds.
Greenstone Geothermal reports that it is working on two prefeasibility projects for deep geothermal projects. Both projects are for mining clients, with one client based in the Western Cape and the other in the Witwatersrand area. If these projects are successful, mining houses will be among the first to use this kind of energy generation, says Madhi.
Meanwhile, he explains that, with shallow geothermal energy, the ground needs to be drilled to a depth of between 5 m and 150 m to capture heat, which is then converted to thermal heat using ground source heat pumps. “At this depth, the earth is not hot enough to generate electricity, but the energy is suitable to build a thermal power station that can provide thermal energy for hot water, cooling, heating and refrigeration purposes,” he adds.
In this way, office buildings, industrial complexes, shopping malls, schools and residential buildings can be cooled or heated and can be supplied with hot water far more efficiently than with traditional heating and cooling solutions, he notes.
“We are currently working on various shallow geothermal projects for residential and commercial clients. These projects are at an advanced stage and are in the process of being commissioned,” adds Madhi.
The company says that geothermal energy is an affordable form of energy generation because, once all the equipment to transfer the heat from underground is in place, electricity can be generated for years at low cost, with minimal maintenance.
Greenstone Geothermal reports that, although the geothermal industry in South Africa is still in its developmental stages, there is interest from potential clients, which are starting to understand the benefits of this energy source.
“Prior to the electricity crisis in the country, this type of energy generation was not fully explored – there was no need for it because electricity was affordable and reliable. But now, with rising costs and more emphasis being put on using renewable energy, geothermal energy is one of the options,” he says.
Meanwhile, the company reports that a significant challenge for this industry is the lack of understanding, in gen- eral, in the market regarding how geothermal energy can be applied in the South African context.
A further challenge is that there are currently no rebates and incentives to promote the use of this technology in South Africa. Support from stake- holders to introduce rebates for geothermal energy use should also be encouraged, he says.
The company reports that it will also be exhibiting at the Energy Indaba and that it will have its full range of products on display. The products are suitable for commercial, residential and industrial applications.