With South Africa’s im-pending energy crisis and the fact that most rural households do not have access to energy, biogas could potentially become a viable solution.

Biogas is a low-cost form of energy derived from renewable resources such as animal dung, human waste and other organic materials.

Greg Austin, a director of Cape Town-based Agama Energy – reportedly South Africa’s first sustainable-energy services company – is currently working on a year-long research project for the Department of Science and Technology, which will outline the benefits of biogas technology in South Africa.

Anaerobic digestion is a renewable-energy technology that ensures a distributed energy production where the energy is produced at the point of consumption or demand.

A biogas digester – in which the biogas is produced – also provides an ideal on-site, water-borne sanitation sys- tem, as well as an integrated organic kitchen and garden waste-recycling opportunity. The research programme, titled ‘Preparatory steps towards establishing a national rural biogas-dissemination programme’, is scheduled for com-pletion in February next year and aims to illustrate the benefits of the technology on a macro- and microlevel and to outline a biogas programme plan for South Africa.

If rural households can convert from fuel-wood to biogas, health benefits will be noticed immediately, explains Austin.

Burning of fuel-wood causes severe respiratory and eye problems.

Moreover, the use of biogas will prevent forestry from being used in an unsustainable manner.

There are also time benefits, as rural womenfolk take up to two hours a day collecting fuel-wood.

If the programme is recognised as feasible, there are two alternatives that can then be applied: a subsidy or grant-funded approach, which may become bogged down as an energy-political issue, or a market-driven approach.

Currently, it is estimated that South Africa consumes about 9% of renew-able energy and, of that, about 7% is derived from biomass, including fuel-wood.

South Africa’s target for the use of renewable energy is an additional 10 000 GWh a year by 2013.

Austin is developing real projects on the ground, while simultaneously aiming to obtain a foothold for the technology in South Africa.

Through the use of anaerobic digestion – a technology that was developed in China and has been used for more than 60 years – organic waste can be converted into energy.

China has installed over 12-million small digesters to date, and has plans to install around a million every year until 2050.

Austin has been using the technology in two different ways.

The first application of anaerobic digestion is producing energy from animal waste and the other application is an ecological sanitation approach to wastewater treatment, which produces biogas as a by-product. Biogas is about two-thirds methane and is ideal for combustion, explains Austin.

With regard to the sanitation application, the overflow from the biogas digester requires aerobic treatment, which is done by using a constructed wetland. After this process, the water is then reusable and nutrient-rich.

This method recycles water without the use of any energy, as it is all gravity-fed.

Agama Energy is in the process of implementing projects in South Africa and Lesotho, in conjunction with a Maseru-based nongovernmenal organisation (NGO) called Technologies for Economic Develop-ment (TED).

In the past year, they have implemented five projects in South Africa and 15 in Lesotho, all of which have been market-driven.

One of the five projects implemented in South Africa is at the Ivory Park Ecovillage, in Midrand.

The project is being sponsored by an NGO known as the Eco City Trust.

The sanitation plant, which is 95% complete, will provide sanitation for 29 houses and about 116 people.

In another ecological sanitation project about two hours outside Cape Town, in Groot Winterhoek, a digester has already been commissioned and is currently treating wastewater at the site.

The project was done on behalf of Cape Nature Conservation. Currently, the water is being discharged, but once a pump is installed it will be gravity-fed into the food gardens and the gas will be used in the communal kitchen.

Austin tells Engineering News that Agama Energy has another five similar projects in the pipeline.

The technology also lends itself to yet another application, namely the treatment of food waste, for example, in the hospitality industry.

It is often problematic for the hotel industry to dispose of food waste in an efficient and sustainable manner.

This technology provides such companies with an opportunity to recycle waste, while drawing out the necessary water and nutrients for irrigation purposes.