Opinion

Should we look towards battery power?

Peet du Plooy

Battery-powered SA: Energy independence for the home and for the nation

Batteries instead of power stations? Driving future cars today? Saving money AND the environment at the same time? Are these things possible - or just a pie in the South African sky? 

Part of the solution to South Africa's energy crisis - both the shortage of electricity and spiraling oil prices - may well lie in embracing battery power. Far from being a joke at Eskom's expense, batteries of all kinds are presenting the world with new options for secure and efficient electricity. 

Battery power is not new to us. In many poorer and rural areas, batteries provide a handy form of energy storage that can power lights and appliances at home or in businesses. In wealthy areas, batteries are in use everywhere, from cell-phones to laptops to backup/uninterrupted power supplies (UPSs). The recent rolling electricity blackouts saw a variety of battery-powered electricity back-up devices hit the market. 

Batteries do not generate electricity, but can store it in times of excess to be used again when there is a shortage in supply or when grid-electricity fails. With a large enough number of batteries, the country could store extra energy during off-peak times and draw on it again during peak demand times, similar to hydropower storage facilities. Supplying peak demand from energy stored off-peak lessens the need to build expensive new power stations.

Besides back-up battery systems for homes and businesses, a major source of energy storage in the future may be the batteries used by Electric Vehicles (EV's). The battery in an electric vehicle is like a petrol tank for electricity - it can be filled up when an electricity supply is available and used when required. 

By saving on petrol, an electric vehicle costs much less to run than a petrol vehicle (4 US cents vs 55 US cents per kilometer respectively). It can be powered by renewable energy like solar power, but even when running of electricity from coal power stations, it produces a fifth as much greenhouse gas for traveling the same distance, compared to coal turned into petrol through normal coal-to-liquid processes. 

The idea of electric vehicles is not new, but it is only in the last few years that this technology has become competitive with internal combustion engines. The innovation that made this possible came from unexpected quarters: new batteries developed by the cell-phone and IT industries are much lighter and more powerful than the traditional heavy batteries.

South Africa is also playing a leading role in furthering electric vehicles:

• South African-born venture capitalist Elon Musk is the main investor in the world's hottest electric vehicle, the 0-100k/h Tesla Roadster.
• The SA Industrial Development Corporation (IDC) recently announced a partnership with another international company for building the sporty Velozzi EV in South Africa.
• The cute Norwegian Think City EV is powered by Zebra-type batteries, developed by SA's CSIR.
• In Cape Town, a group of ex-defense engineers formed the company Optimal Energy to build a world-leading but proudly South African EV.
  

How do we power EVs when electricity is scarce? Electric vehicles do not require a lot of electricity! In fact, one US electric utility found that the US could run over 80% of the vehicles in the country on spare capacity that already existed in the system by using off-peak power.

It's common knowledge that oil is more expensive than coal: at a cost of $80 per barrel, South Africa's oil imports cost the country R65 billion a year - a large chunk of the R80 billion it would cost to build a new coal-powered station. Even when run on coal-powered electricity, electric vehicles make much more efficient use of natural resources, with less impact on the environment.

Oil has also been central to many world conflicts in regions like the Middle East. It is not surprising that one of the world's biggest initiatives to advance EVs, Project Better Place, was started in Israel with backing from its government.

The project aims to roll out battery recharge stations where empty batteries can be instantly exchanged for charged ones, the way we fill up with petrol today. These charging stations are like "virtual power stations" - charging batteries off-peak when grid-electricity is cheap; and supplying electricity from charged batteries back to the grid at peak demand times when suppliers can demand a premium.

Renewable energy, batteries and electric vehicles work well together. You charge batteries while parked and when the grid goes down you run your building's essential electricity needs from the car. You can be energy independent and sell back spare energy to the grid at peak demand times.

By buying a petrol or diesel generator, you end up paying for technology that is far less efficient than the power station you're replacing. By buying a battery backup, you get one step closer to using renewable energy and becoming a virtual power station.

Prepared by Peet du Plooy, Trade & Investment Advisor at WWF South Africa, February 2008

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 Reproduced with permission from WWF-SA. © [2007] WWF- World Wide Fund For Nature (Formerly World Wildlife Fund). All rights reserved.

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