solar-assisted coal

South Africa's short-term energy crisis is lack of generating capacity to meet peak electricity demand. A two-pronged approach could relieve Eskom of its headache: reduced consumption (adopting more efficient technologies in homes, offices and factories, and using heating and cooling systems with lower energy requirements) and adding distributed generation of electricity. Some aspects of this strategy would be quick to implement, given the necessary political will and incentives to get things going, and the slower aspects shouldn't be any slower than building big new power stations.

But the bulk of electricity is likely to come from large power stations for some time, so the key choice is between coal and nuclear power, each with its inherent risks. If coal remains the dominant fuel of choice for Eskom, then the biggest environmental issue is carbon emissions. Australia's CSIRO is doing research in a number of fields related to energy, including postcombustion capture (PCC), which is a method of captuing carbon dioxide from flue gases. Though not proven at an industrial scale, PCC is said to capture 85% of CO2, which would dramatically reduce GHG emissions (assuming the captured carbon can then be sequestered or used in some other process, another big "if"). A drawback with PCC is that it requires energy, so either the power station must suffer reduced efficiency, or another power source needs to be added to operate PCC. CSIRO is looking into solar thermal collectors to provide that source, which would be an interesting synergy between solar and fossil fuels.

The CSIRO is also looking at solar thermal systems designed for heating, cooling and electricity generation for individual buildings. These are not just for small-scale applications, but for buildings the size of shopping centres.