Eskom is to switch to a new ally in its continuing bid to keep the lights on: the sun. The power utility — which has been battling in recent times to meet demand, especially during cold spells — is understood to be finalising an aggressive financial programme to incentivise the use of solar water heaters. Industry sources say close to a million solar-powered water heaters could be subsidised over a five-year period to the tune of R2-billion.
The last census showed the country has 10million households, suggesting just how ambitious Eskom’s plan is. It also indicates how important a part of the energy mix South Africa’s bountiful solar resource will be in the future.
General manager of investment strategy Andrew Etzinger says an executive decision was taken last year to strongly support the introduction of solar power for water heating. He says the utility has been investigating the widescale introduction of solar heating. ”Eskom strongly supports developing mechanisms to reduce the cost of solar heating and scale up the size of the industry.”
The scale and potential impact of the new programme has required research into what benefits could flow from using solar power, and to what extent the domestic industry is able to support the aggressive introduction of a solar-powered regime.
Etzinger says the proposed programme is being finalised and is expected to be put to the Eskom board at mid-month. It is understood that the new programme will begin shortly thereafter.
Consumers who switch to solar water heaters can expect to have about 30% of the cost of a unit subsidised by Eskom as part of its demand-side management programme. A R15 000 unit will therefore cost about R10 000 with the installer billing Eskom on a monthly basis for the subsidised portion.
The new initiative will be a massive boost for the country’s tiny solar industry that, at present, sells only 7 000 to 10 000 units a year. The country also stands to gain in job creation as the industry is relatively labour intensive.
Figures supplied by environmental conservation organisation WWF show that improving residential energy efficiency by installing solar water heaters can save enough energy (6% to 7% of national energy consumption) to provide for the 30% of households currently without electricity. It would also create about 50 000 jobs with a payback period of less than three years (and continued savings thereafter).
Eskom has spent the past year running a pilot across the country and entering into discussions with the solar industry to ensure it can implement a massive programme on a sustainable basis.
One immediate problem that was identified is that, even if the local industry doubles in size, it will only be able to supply 20 000 units, way short of the up to one million envisaged by the new initiative.
The subsidy to users is understood to have been approved in principle by energy regulator Nersa and will come from a tariff levied on electricity consumers. This amounts to R600million annually to implement demand-management programmes to reduce the need to install new electrical power capacity.
The subsidy is pitched at a level below that of the cost of building new power stations, meaning that the savings achieved make economic sense.
The pilot study of 50 systems implemented countrywide has shown to be highly attractive; 36 solar units produced savings of 22MW in a five-month period. This is a saving of 24,1 tons of carbon dioxide and 27 000 litres of water, which is what is required to produce this amount of power from a conventional coal-fired plant, according to consultant Jon Adams of the Sustainable Energy Society of Southern Africa. He analysed the Eskom pilot data, which was produced as part of a joint investigation by Eskom and Sessa into quantifying the benefits of hot water powered by solar.
The tracking of the 50 pilot sites has shown, in particular, that the use of timer switches in conjunction with solar is extremely important. Solar geysers typically make use of the sun during the day, but switch to electrical power on cloudy days. The use of timer switches in the pilot reduced the electrical component from 56% to 34% of total.
The use of the timing switches reduces the amount of electricity the consumer uses. It can also be used to reduce the load on Eskom’s network during peak times, when as much as 40% of household electricity use is for hot water.