MARCH is Energy Month, a time for the City to look at sustainable energy technology. Already, it installs solar water heating systems in low income housing, among other initiatives.

SUSTAINABLE energy will be in the spotlight during March, as it has been declared Energy Month by the national Department of Energy; in addition, 2012 has been cited as the international year for sustainable energy access for all by the United Nations General Assembly.

Solar water geysers have been installed in Cosmo CityJoburg is getting into the spirit of things by celebrating the initiatives it has already put into place to optimise the sustainability of the city’s energy sector. It is also announcing programmes that are in the pipeline.

Thabo Mahlatsi, the director of energy in the City, says: “The energy department is in the process of research and development of technologies that will generate electricity without using fossil fuels, namely hydro.

“We are looking at creating a low carbon economy,” he says.

There are a number of initiatives in the pipeline to achieve this. Just two are introducing more solar water heating systems and revamping street lighting by replacing existing bulbs with low-energy, high-efficiency LED (light emitting diode) ones.

The solar water heating system initiative has been in place for some time. It was first rolled out to Cosmo City in 2007 and then again in 2010. Mahlatsi says there are plans to roll out more solar water heaters, with a focus on Devland and the Lehae housing development, both in Soweto.

“It will cost approximately R200-million over five years,” he says. “Demand side management funds will contribute to this.”

Solar water heaters

Solar water heaters promote renewable energy and energy efficiency. The heaters used in the City’s project for low-income housing are low-pressure, containing an evacuated tube close-coupled thermo siphon system with a water tank mounted on top.

The tank and vacuum tubes are filled with water and then heated by the sun; as the water gets warmer it rises and mixes with the cold water in the tank, eventually heating all of it.

In addition, the energy directorate is also looking at the possibility of implementing and switching over to direct current (DC) microgrid technology. It is a cheaper and more efficient form of energy as it focuses on renewable technologies.

City Power is installing power saving bulbs“Based on the DC system, all houses will be completely off the grid. We need to experiment on it first, though, which we will do this month,” he explains. “We need to raise awareness of what it means practically, so we will be demonstrating DC microgrid technology.

To this end, Mahlatsi will be in Durban today to talk to the minister of energy about off-grid technologies and testing.

There are, of course, other initiatives that have been implemented by the City in the past to create a more sustainable energy sector. This includes smart metering, which enables two-way communication between the meter and the central database. The first major roll-out of these meters was done in Roodepoort, where 20 000 smart meters were installed.

Smart meter

A smart meter records consumption of electricity in intervals of an hour or less and communicates this information back to City Power’s database at least once a day for monitoring and billing. Billing customers by time of day allows them to see when they consume the most and adjust their behaviour accordingly.

This in turn makes it easier for consumers to manage their energy use and reduce their bills and their carbon emissions.

Joburg also has an above-average performance on the African Green Cities Index, the results of which were published in November 2011 by Siemens and the Economist Intelligence Unit. Joburg performs particularly well in land use, energy and carbon dioxide emissions, transport, air quality and environmental governance.

“It is about creating a liveable and sustainable city by building a low carbon city,” says Mahlatsi.