Feature

Green with Energy

Dr Garth Cambray

Renewable energy is a big buzzword at present. For the first time in Africa, one can now buy guaranteed green energy.

Owning a Mercedes Benz is often enough to make ones friends green with envy, but now the SA manufacturers of Mercedes Benz, Daimler Chrysler SA have gone one step further - they are now green with their energy (at their head offices in Pretoria at least). In highly developed energy markets such as the US and Europe, small renewable energy producers have for a number of years been able to produce electricity at sources where the conditions are right and then allow that energy to enter the electrical grids, measuring the power added to the grid, and then at another point, often very far away, a company buys an equivalent quantity of energy from the grid. As an example of this sort of thing, Wholefoods Network, a Fortune 200 chain of organic food supermarkets in the US has purchased sufficient energy from a wind farm company to supply all its outlets across North America. In this way, we see a company with a green image actually acquiring additional customers by using more expensive, more market acceptable power.

Renewable energy can be defined as any source of energy which can be produced from something that can replace itself - such as wind, sustainable biomass, solar energy, tides and so on. For many years South African consumers have had renewable energy in the sense that Eskom operates large hydroelectric schemes, such as those on the Orange river. This electricity has however not been sold at a premium to those that would pay more for it, but has instead just been diluted into the national grid and a consumer buys a mixed bag of coal, nuclear and hydroelectric power at an average out price.

This has changed now in South Africa - it has become possible to purchase renewable electricity. The energy startup company, Amatola Independent Power Producers (Pty) Limited - trading as Amatola Green Power (AGP), has begun selling green electricity. AGP purchases electricity from producers such as sugar mills, which, as part of their process burn off bagasse to generate both heat and electricity in sugar mills. The energy balance is such that more electricity is generated than is required by the sugar mills, and hence this electricity is sold onto the grid and then retailed by AGP.

The Komati sugar mill of Transvaal sugar limited. The steam visible is waste low energy steam, a by product of the process of burning bagasse to boil water and drive a steam turbine, thus generating power.

In the case of AGP the ability to sell green power has depended largely on access to the national electricity distribution system - the power grid which spreads energy around South Africa. The cooperation of the national power utility, Eskom, is obviously highly important in this regard. As the number 14 carbon emitter in the world, South Africa urgently needs to reduce its non-renewable energy consumption and hence the government, in the form of the Department of Minerals and Energy, which endorse such projects and has set a national target of the country producing 10 000GWh of renewable energy by 2013. As an example, for every R1000 worth of electricity purchased from AGP, the consumer ensures that 2.3 tons of fossil carbon is not emitted to generate an equivalent amount of non-renewable energy.

This picture shows how a green electricity supplier provides electricity to a distribution network and measures exactly how much power it puts on the network, and then at the consumer end, the amount of electricity used is monitored, and thus the consumers can buy electricity representing the amount of green energy supplied to the grid.

From an entrepreneurial perspective, as new technologies become more effective, being a small electricity supplier selling to a company such as AGP will become viable. Large feedlots which produce copious quantities of manure can set up effective digestors to convert waste into methane and use that to power small turbines. Small hydroelectric projects, and larger hydroelectric projects in underdeveloped parts of Africa can eventually fit into this picture too.

In a country such as South Africa, green power is probably still however perceived as a luxury which will be consumed by the wealthy to off set their large environmental footprints. This is off course acceptable, and good. In a country like India the environment is under serious threat - and in many cases biomass is the main source of energy. In the state of Uttar Pradesh on the upper reaches of the Ganga river, huge sugar cane plantations provide monstrous quantities of biomass. In between the cane fields, hundreds of thousands of hectares of rice paddies provide a lot of rice, but also, a lot of rice husks which are used as a fuel. Hence industries in the area purchase bagasse and rice husks to power boilers, electricity plants, sugar mills, steel works and brass smelters. Interestingly enough plant managers approached were not aware of the concept of renewable energy, tapping into biomass for energy based on the low cost rather than global pressures for green energy production practices. So in a country like India, poverty in a way has made companies use renewable energy, with the result that Indians are escaping poverty faster than any other nation on Earth. It is fascinating that the South African sugar cane industry, which was made possible by the influx of people from India in 1860, is the foundation upon which our first renewable energy company, AGP, is being built.

More information:

  More information www.amatolagreenpower.co.za 

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