Tanzanian to Produce Anaerobic Digesters to Generate Clean Gas

As Tanzania goes through its worst energy crisis in recent years due to low electricity generation, the Centre for Agriculture Mechanization and Rural Technology (Camartec) has embarked on large-scale production of biodigesters that could help many families cope with the crisis.

The anaerobic digesters (which operate without oxygen) are intended to produce biogas, a pollution-free and clean gas, which ordinary families of small holder farmers and other people in the low and medium income bracket can use to produce energy for their daily domestic needs, such as cooking, heating and lighting.

The Arusha-based Camartec is implementing the project as a component of the African Biogas Partnership Programme (ABPP), known as Tanzania Domestic Biogas Programme (TDBP), funded by Netherlands’ ministry of Foreign Affairs, through its directorate of international cooperation.

The ABPP, on the other hand, is part of a broader programme of Dutch international cooperation, targeting provision of sustainable energy to 10 million people in African countries, including Tanzania. Others are Senegal, Burkina Faso, Uganda, Kenya and Ethiopia.

The coordinator of the programme, Mr Lehada Cyprian Shilla, is among officials who have expressed optimism over its potential to alleviate current energy woes. The programme was officially launched recently at Camartec premises on the outskirts of Arusha, although it has been operational for some time prior to the formal take off.

According to him, a total of 12,000 biogas plants are to be constructed under the first phase of the project planned to cost Euro 16 million during its implementation until 2013. Mr Shilla noted that it would provide cleaner and safer energy solutions at the household level.

Until recently, when it was officially inaugurated by Vice President Mohamed Gharib Bilal, a total of 1,439 units had been constructed under the programme in various regions of the country–giving Tanzania a lead ahead of other nations where the initiative is being undertaken in Africa.

Beside providing an alternative source of energy to households currently faced with rising kerosene prices and worsening electricity crisis, the programme is expected to stimulate the private sector’s participation in the development of biogas technology and sale of a gas “that is affordable and simple in rural and peri-urban households,” he said.

The launching of TDBP has, in a way, rekindled memories of the 1980s when Camartec pioneered biogas technology at a time when it was not even popular in many countries. The innovation was intended to be among the responses to skyrocketing oil prices in the world market during 1970s.

But since then, the state-owned institution had not been active in promoting the technology, unlike an array of other entities involved in the sector, such as non-governmental organisations (NGOs), research and development organisations, development agencies, schools and colleges. The private sector and individuals are also currently involved in development of the clean technology.

However, when it was finally decided that Camartec should host the new programme, it was easy for its officials and technicians to tap in their past experience in clean energy supply and waste management projects.

In rural Tanzania, biogas knowledge is something many farmers and livestock keepers must have lived alongside for many generations without realising that it could turn around their lives.

It is not energy necessarily produced from exotic plants. It is simply a gas produced by the biological breakdown of ordinary organic matter in the absence of oxygen. It comprises mainly methane and carbon dioxide and may have small amounts of hydrogen sulphide and other gases.

A plant used to produce biogas, also known as a biodigester, is an anaerobic digester that treats farm wastes or energy crops. This has been mostly the case in the developed countries where in recent years the technology has assumed new importance because of advanced methods of waste treatment.

In most of the developing countries, however, domestic biogas plants convert livestock manure into gas. The technology has been feasible for small holders with livestock producing at least 50 kilograms of manure per day.

Temperature affects the fermentation process. With an optimum temperature at 36 degrees centigrade, the technology is much suited to those living in tropical climates where large parts of African, south Asian and Latin American countries are found.

The gas has several advantages. It is pollution-free (clean). Indoor air pollution is considerably reduced through fermentation in the digesters, waste from the animals and other biodegradable matter. The cooking energy also relieves women the energy-sapping and time-consuming task of collecting firewood.

The slurry, on the other hand, is a clean organic fertiliser that potentially increases agricultural productivity.

Mr Shilla emphasized during an interview recently that successful implementation of the project hinged on good public-private partnership and local NGOs involvement.

Netherlands, known to be much ahead of many countries in the world in waste treatment technologies, is involved in the programme through its Foreign Affairs ministry.

Two Dutch organisations HIVOS (Humanist Institute for Development Cooperation) and SNV (Netherlands Development Organisation) have partnered with Camartec in the initiative.

The project has already won Camartec an award from the African Biogas Partnership Programme (ABPP) in recognition of its efforts in promoting the dissemination of domestic biogas in Tanzania. Its director general, Mr Evarist Ng’wandu received the award on behalf of the centre in Nairobi.

TDBP began in 2007 following a feasibility study by a German aid agency, GTZ (now renamed GIZ). Camartec was selected as a national agency to coordinate the programme. The centre was established in early 1980s to promote appropriate agricultural and rural technologies. It is credited for having pioneered the biogas technology using animal and domestic wastes.

Energy sources that have contributed to the energy balance in Tanzania by 2009 are biomass fuels (firewood, charcoal and farm residue) all accounting for 90 per cent petroleum (8 per cent) and electricity (1.2 per cent), while solar and biogas combined contribute about 0.8 per cent.

The main energy consumption sectors are household, manufacturing, agriculture, commerce, transport and mining. The household sector, however, consumes the largest share (91 per cent) of total energy available in the country mainly for cooking and lighting.

The biogas option is preferred as a way of lessening dependency on firewood and charcoal as the main energy sources, which is feared to be unsustainable and could plunge the country into serious environmental problems.

Experts have cautioned that although Tanzania is still rich in natural resources, the rapid population growth would outstrip regeneration capacity of the vegetation. Only 2.5 per cent of rural dwellers, who constitute 80 per cent of the population, are connected to electricity.