Turning Organic Waste Into Energy

Biogas is a multipurpose technology, which assists in addressing economic, health, social and environmental problems. Developing and spreading this technology would certainly minimize dependency on charcoal and firewood, as well as improve peoples’ lifestyles, especially in developing countries like Ethiopia. In line with this, Ethiopia has finished implementing the first and second phases of its National Biogas Programme, from 2009-2013 and 2013-2017, respectively. During that period, the country was able to disseminate 18,000 biogas digesters. However, the supply is still far from satisfying the demand. According to estimates, the number of potential beneficiaries of biogas technology is as high as four million households. EBR’s Ashenafi Endale investigates the major factors that have held back the spread of biogas.

When workers of the then-Ethiopian Electric Power Corporation, now Ethiopian Electric Utility (EEU), were installing electric power distribution lines for residents of Bishoftu (Debrezeit) ten years ago, they overlooked Shumi Deyas’s house, located just two kilometres away from the town centre. After repeated and fruitless efforts, Shumi, a 68 year old father of seven, turned to alternative power sources, and adopted biogas technology.

Biogas involves converting a mix of organic wastes such as cattle manure and water to energy by installing a bio-digester. Once installed, the digester continuously converts organic wastes known as ‘dungcakes’ to a mix of 50–70Pct methane and 30–40Pct carbon dioxide as well as hydrogen sulphide, water vapour and ammonia. While the digester changes the methane into energy, the waste from it can be used as high quality fertilizer. With one kilogram manure and one litre of water, a four cubic meter digester (the smallest size found in Ethiopia), generates energy that lasts for two hours, and that can be used for cooking and lighting.

Shumi, who has 14 cattle and easy access to a river that passes by his house, was in a good position to make use of the technology. He covered half of the ETB8,000 cost of a six cubic meter digester. “Four cattle provide enough manure for lights and power for cooking for my family,” he explains. Ten years down the line, Shumi has travelled all over the country to explain the benefits of using biogas.

Like Shumi, most Ethiopians live without grid coverage, and lack direct access to electricity. According to the information obtained from the Ministry of Water, Irrigation and Energy (MoWIE), access to electricity increased from 12.7Pct in 2000 to 43Pct in 2017. At the same time, 92Pct of the country’s energy comes from firewood and charcoal. This, in turn, has caused an energy and environmental crisis over the last four decades.

The energy crisis has been wreaking havoc in Ethiopia. Currently, per capita electricity consumption in Ethiopia stands at 100 kilowatt hours per person, which is low compared to the sub- Saharan Africa average of 521 kilowatt hour per person. The country envisions increasing access to electricity to 90Pct by the end of 2020.

On the other hand, the intensive dependency on firewood and charcoal as sources of energy has depleted forest coverage, which has dwindled from 30Pct in the late 19th century, to less than 10Pct in 2000s.

These energy and environmental crises have left a space for a clean form of sustainable and modern energy. Unfortunately, Ethiopia has one of the lowest rates of access to modern energy services. Waste and biomass are the country’s primary energy sources accounting for 92.4Pct of the country’s annual energy supply, followed by oil (5.7Pct) and hydropower (1.6Pct). The share of wind, solar and geothermal energy accounts for the remainder.

Especially for a country like Ethiopia where close to 30 million tons of dung are available annually from 59.5 million cattle, the benefit of biogas is indispensable. The available organic waste resource in the country is enough to produce 12.5 million kilowatt hours of energy. In a similar manner, energy obtained from a one cubic meter biogas digester is equivalent to the energy from five kilograms of firewood, 1.5 kilograms of charcoal or 0.6 litres of kerosene.

Yet, biogas wasn’t introduced to the wider population until 2009, with the launch of the National Biogas Program (NBP), although biogas technology had first been installed in 1979 at the former Ambo Agricultural College. The NBP started with a feasibility study and pilot program by SNV, the Netherlands Development Organisation, in 2008, where 98 biogas digesters were provided to users in the states of Oromia, Amhara, Tigray and Southern. When the pilot program proved successful, SNV, along with the MoWIE, launched a full-fledged program, lasting until 2013.

The NBP was introduced mainly to tackle the fast dropping forest coverage in Ethiopia. Later, the programme became part of the Climate-Resilient Green Economy strategy, which Ethiopia launched in 2011. The strategy envisages achieving resilient economic growth by 2025, with net zero emission.

“When we approached the government ten years ago, there were only a few bio-digesters in the country, installed under different initiatives but not coordinated,” explains Aster Haile, senior implementation support expert at SNV.
On the ground, the program is executed by development agents. “There are at least four million farmers who would be ideal candidates to use biogas,” estimates Birhan Tewolde, biogas engineer and acting director of the NBP at MoWIE. “This shows that there is a big demand for digesters.” Official estimates, however, put the number of potential beneficiaries between 1.1 and four million households.

Hivos, a Dutch development organisation, has been funding the first and second phases of the NBP. Out of 10,000 bio-digesters planned during the first phase, 8,000 have been installed at a cost of ETB205 million. The second phase, which covers from 2014 to 2017, targets the distribution of 15,000 digesters, of which only 10,000 have been distributed at a cost of USD 11.2 million.

According to a study conducted by Linda Manon, assistant professor of Energy and Industry at the Delft University of Technology in the Netherlands, titled ‘Ethiopia’s emerging domestic biogas sector’ published in July 2016, one of the major goals for the second phase of the program has been improving the involvement of the private sector, a goal not accomplished in the first stage of the NBP.

Currently, there are at least two improved biogas stove manufacturers in each regional state, according to Bekalu Mola, private sector development expert at SNV, while 26 enterprises are licensed to build digesters. “SNV is preparing a framework, which will allow the private sector to be involved in the procurement and distribution of biogas technology as well as access finance and incentives,” he explained.

Manon argues that the highly centralized and hierarchical nature of the NBP limits the role of the private sector. Although private companies are beginning to appear in the areas of installation and commercialization of renewable sources of energy, especially solar energy, several factors have influenced poor private sector involvement in biogas sector.

On top of limited participation of the private sector and low penetration of bio-digesters, their malfunction rate ranges between 30Pct and 50Pct, according to Birhan. Senait Seyoum, a research assistant at African Livestock Policy Analysis Network, in her study entitled ‘The economics of a biogas digester’ also reveals that the major risk when it comes to bio-digesters is their life span and availability of maintenance services. Even if the life span of digesters reaches is up to two years, the prototypes tested while conducting the study failed in less than one year. As a result, Senait stresses, there is need for a maintenance service or training programme to teach users how to maintain biogas digesters.

Shumi says even though many farmers want to install digesters, there are no masons available nearby. “Farmers are discouraged mainly because officers at lower administration levels take a long time to approve the required finance and because there are no masons nearby to help with maintenance, in case the digester fails.” There is only one biogas expert working at local energy bureau at Shumi’s town.

“We know we are behind our targets,” says Birhan. “It should not take ten years to build less than 20,000 digesters. However, constructing bio-digesters needs special skill.”

The most common bio-digester technology in Ethiopia to date is the fixed-dome digester. This type of digester, which is made up of a stationary underground structure constructed using cement, bricks, sand and aggregates, is constructed by masons. In addition, a biogas piping system, which consists of PVC pipes, flexible hosepipes or metal pipes, needs to be installed. “Although SNV and MoWIE train masons to build digesters, most of them switch jobs to the construction industry because they aren’t well paid,” Aster stresses. So far, 2,000 masons have been trained.

Currently, MoWIE and SNV are preparing to implement the third phase of the NBP, the National Biogas Scale up Program, which will run from 2017 to 2022, and is planned to increase the coverage of the program from the four regional states to eight, and install 36,000 digesters, benefitting 180,000 people. The program is expected to cost around USD 26.4 million.
Worku Behonegne, country director of SNV Ethiopia says the organization is now working on integrating the programme with other projects in the agriculture, health and sanitation sectors. “The program will become more successful if it is executed parallel with projects implemented to uplift the living standards of rural communities,” he argues. “It must also scale up from benefiting small scale households to medium and large farmers as well as industries.”

“If there was the awareness, the technical part would be simple,” stress Birhan. “We could achieve the 36,000 digesters planned for the scale up programe in less than five years, if the challenges are solved.”

All stakeholders agree that biogas has been underutilized so far, despite its multiple benefits to energy, agriculture productivity, health, sanitation and environmental protection. “I could not have saved money, become more healthy and travelled all over the country without realizing the benefits of using biogas ten years ago,” agrees Shumi.

The experience of farmers who use biogas as a source of energy, including Shumi, also reveals that the slurry produced by biogas digesters is very useful to raise agricultural productivity and improve soil fertility, as it is more nutrient rich than commercially available fertilisers. “By using slurry as fertilizer, my annual agricultural production increased by at least 15 quintals compared to when I used commercially available fertilizer,” he explains. Shumi owns five hectares of land and harvests 90 quintal wheat, 20 quintal of teff, and 45 quintal of chick peas per hectare.
“A farmer can recoup the investment in the digester in at most two years when taking into account productivity from the slurry fertiliser,” argues Aster. “However, for Ethiopia as a whole, more effort is needed from the government and NGOs, as well as coordination with regional energy bureaus and experts on the ground, in order to create more success stories.”

6th Year . June 16 – July 15 2018 . No.63