FEATURE

GETTING OUR HEADS AROUND THE SUN

Understanding solar energy’s response to Eskom

“Quick! Boil the kettle! Charge the laptops and phones! Heat your food one last time!” These are the hysterical cries of every household in South Africa in the 10 minutes prior to scheduled loadshedding – a state of frantic existence that we have become used to.

Load shedding seems to be here to stay, with some experts reporting that even when Medupe and Kusile power plants fully come on line, we still may be in a position where scheduled outages will be necessary. So, what is the solution? There are a few solutions, some fairly immediate, some which will provide a longer, more sustainable option to the South African market. Those of us with Zimbabwean mates, know the story (the smell and the noise) of generators – a quick, easy and effective way of rolling back the dark pall of Eskom’s load-shedding programme. An entry level 5KvA generator, able to light a house and run a few appliances, will set you back only a few thousand rand and is easily sourced at a local Builders Warehouse or Makro store. Generators allow you a “plug and play” option, ensuring that you will have light as soon as you fill the tank and plug it into your main circuit. The drawback of the generator though is not only the awful racket it makes, nor just the fact that your neighbours may be taken on a chemical high from the fumes, the real drawback is a generator’s sustainability. These machines cost more to run in terms of rands per watt than what our dear friends from Eskom charge us – and with the fuel price about as consistent as a Bafana Bafana performance, this is

not a position I would feel comfortable to bargain from. A number of years ago, European countries, such as Germany, were forced to consider alternative sources of energy. The German government set themselves the goal of offsetting 5% of the national electricity demand through solar energy. Through a dynamic ”2 to 1 payback” scheme, Germany was able to achieve this target in under four years. Their plan was to encourage households and businesses to install solar powergenerating systems, large enough to not only supply the need of the individual but to also have a small surplus amount, which could be pumped back into the national grid (This is known as a gridtied system). The private generators would be paid twice the value of what they were charged for the electricity. The result: Germany now produces more than 35% of the world’s solar energy, almost 39 gigawatts at any one time. Interestingly, according to Eskom, South Africa’s total electricity demand is 34gW at peak times. Considering these details, in the light of the fact that the Medupe power station costs almost R32 per watt to run and that the carbon emission tax for the plant is over R1-billion annually, a viable alternative source of energy for the consumer is desperately necessary. Eskom would not disagree either. In a recent press release, Eskom encouraged the increased usage and development of renewable energy by “independent power producers” in order to alleviate the demand on our “constrained power system”. That option for the small businessman and the everyday household must be solar energy, however, this form of energy seems to be ”clouded” in misconception and uncertainty. It’s a misconception worth clearing up, though. The first issue to clarify is the reason for any particular installation, that is, do you wish to save money in your monthly electricity bill or is your aim to get through the four hours of darkness scheduled each day? If load-shedding is your only concern, a battery back-up system is your best bet. From around R6 500 for a battery pack, inclusive of a necessary inverter, you can power your HD television, DStv decoder, wireless router and a couple of LED lights for between three and four hours. So, R6 500 may solve your immediate load-shedding headaches, but it will not stave off the burden Eskom brings to your pocket. In order to avoid the impact of the 12% tariff increases planned by the national energy provider, you need to invest in a complete solar solution. The notion of ”going off the grid” is a fanciful wish, one that will cost you substantially in the hope of accommodating your every energy need.

Rather, the preferred approach is to generate your own power during the day, to heat your geyser, charge your batteries and return the surplus back into the national grid (which is allowed in most major metropoles). Then, you would only have to rely on Eskom during high-use times and after battery depletion. This approach would significantly lessen your initial capital outlay.

To achieve this, you would need photo voltaic (PV) solar panels, an adjusted geyser system, an inverter, which would allow you to add on to your system in the future and to monitor energy production and supply, and finally you would need a set of back-up batteries for the evening’s power demands. A system of this size would cost you around R70 000.

Don’t let this number scare you away, however: this system would not only cover the darkness of load-shedding but it would also effect a 70%-90% save on your monthly electricity bill. A quick calculation means in an average household, you could pay back the full system in four to five years, based purely on savings and projected tariff increases. This model makes so much financial sense that some of the major banks are offering energy-based loans. Unfortunately, we are creatures of necessity, and if this is being read in the comfort of lamplight and air conditioning, there is a good chance that we cannot recall when last the plague of darkness struck. Or how it inconvenienced us. However, a cursory glance at the rest of the world and we soon realise that the challenges of power supply are not an issue of ”if” but ”when”.