A home in the Nelson Mandela Bay municipality is the subject of a pilot project that could lead to South African households producing their own electricity – and selling the surplus to national electricity provider Eskom.
The system has been running since the end of July 2008 and, says the municipality, it will assess results after another six months to decide on a bigger roll-out strategy.
The municipality intends to become South Africa’s first centre of so-called embedded power generation, where houses can produce their own electricity using renewable resources such as sun and wind. Embedded generation is the term used to describe any electricity generating plant that is connected to regional or national electricity distribution networks.
Renewable energy plants, because they do not have to be as large as a power station, are ideally suited to small-scale installations such as households, and therefore are well placed to being embedded in bigger electricity grids, allowing the household to exchange electricity with the grid.
South Africa’s pilot plant involves a typical home in Port Elizabeth fitted with a one-kilowatt (kW) solar panel package, a 1kW wind turbine mounted on a 12-metre mast, and a battery backup.
The battery bank is used to store energy from both the renewable sources and the grid during off-peak periods, and with the Sunny-Backup charger and inverter, power can be generated from the batteries during peak periods, at night, or when the grid is down. Electricity produced by the renewable components is converted to the inverter to 220V so that it can be used in the home.
The excess energy produced is fed into the grid using a special feed-in meter and sold to Eskom at an established feed-in tariff. The entire system is known as a hybrid, because it includes at least two sources of renewable energy – this is to negate any breaks in supply from the natural sources.
The package also includes all equipment needed to monitor and control the electricity-producing devices, so that the municipality is well able to determine the practical and economic implications of the installation, with a view to expanding the project.
If successful, the municipality hopes that the project will lead to a speedy amendment of national laws and regulations, which currently do not provide for decentralised (where energy production comes from various locations instead of only one large plant) production of energy or feeding into the grid. This will allow people to set up their own sources of renewable energy and connect them to the public utility Eskom, selling their excess power at a renewable or green feed-in tariff.
The Nelson Mandela Bay municipality says that if tariffs are beneficially structured so that to sell electricity costs more than to buy, over a period of time the income raised will cover the initial costs of the system. This break-even period will vary according to the tariff; the amount of energy generated annually, the type of systems, and the initial cost.
South African has experienced critical shortages in electricity supply over the last year, with blackouts and load-shedding across the country as Eskom struggling to meet the demand. The Nelson Mandela Bay municipality has embarked on a major drive to investigate the feasibility of renewable energy not only to help households reduce their dependence on the national grid and alleviate the impact of load-shedding, but also in the interests of the environment and to probe alternatives to fossil fuels.
The municipality is in the process of implementing a number of innovative green projects, among them wind turbines, solar heating, electricity generation from solid waste, the waste exchange project aimed at increasing the reuse of waste, and a large scale wind farm. In total, says the municipality, successful bidders submitted tenders amounting to R9-billion ($1.1-billion).
Executive Mayor Nondumiso Maphazi said the green initiatives indicate the municipality’s determination to become a leader in the provision of renewable energy sources.
“These initiatives will set a standard for all the other local authorities to follow. We are well on our way to providing sustainable energy resources, and the main beneficiaries will be our shareholders, the residents of Nelson Mandela Bay," she added.
The South African government has launched an extensive renewable energy strategy following the 2003 publication of its white paper, which has set a target of at least 10 000GWh of energy to be produced from renewable energy sources – mainly biomass, wind, solar and small-scale hydro – by 2013.
According to the Department of Minerals and Energy (DME), attainment of this target will add about 1.667MW of new renewable energy capacity – this could augment GDP to the tune of as much as R1.07-billion ($130-million) a year.
The scheme for national implementation will also bring in governmental revenue of almost R300-million ($37-million), resulting in additional income that will spill over to low-income households, in addition to the estimated 20 000 new jobs. The DME also expects water savings of 16.5-million kilolitres, or R26.6-million ($3.3-million).