Executives of National Cement are moving forward with a plan to use an invasive species of weed to partially replace coal at its plant in Dire Dawa, 515Km east of Addis Abeba,

Native to the Americas and the Caribbean, Prosopis juliflora was introduced to Ethiopia in the 1980s, following a severe drought in the previous decade. The invasive plant has proliferated since, covering an estimated two million hectares (10pc), mostly in arid and semi-arid areas of the country. Growing to 12m high, the plant covers nearly 22pc of the Afar Regional State's landmass.

East Africa Mining Corporation, a sister company of National Cement under East Africa Holdings, has been experimenting with the idea of converting Prosopis juliflora into biomass since 2015. In collaboration with the former Ministry of Industry, the company conducted a study on the feasibility of using the plant as a source of energy for cement plants. The study found one kilogramme of the weed stem can produce up to 4,000 calories of energy, 12pc higher than the power generated from a kilo of locally-produced coal.

The 19 operational cement factories require 4,600tn of coal a day. They have a combined annual production of 18 million tonnes of cement at full capacity.

Another study conducted by the Chemical & Construction Inputs Industry Development Institute six years ago has arrived at similar conclusions. Initially, its officials intended to pilot the biomass project at National Cement and Messebo Cement Factory in Tigray Regional State. Messebo had conducted a study on biomass as an energy source in 2014. It had invested 109 million Br to erect a biomass energy processing plant, converting sesame hay to biomass.

National Cement was chosen as the second candidate because it has conducted a certain level of research in the field, according to Samuel Halala, director-general of the Institute. Its plant has an installed production capacity of 4,500tn a day and consumes around 120,000tn of coal annually.

The Institute has temporarily suspended the trial at Messebo, whose plant is in the outskirts of Meqelle, the seat of the regional state under the control of armed forces fighting the federal government.

The Institute has acquired a biomass harvesting machine for 3.2 million euros, with financial support from the European Union's Climate Resilient Green Economy (CRGE). The 33 million euro programme emphasises economic growth resilient to climate change without increasing carbon emissions. The Prosopis project was selected as one of three beneficiaries three years ago.

The all-in-one machine supplied by the German-based firm, PRINOTH, can produce 160tn of biomass daily. PRINOTH has delivered similar machinery to countries like Namibia and Cuba. The harvested weed is transported to warehouses to be baled and packed.

Samuel disclosed that the Institute, which has been providing consultancy, training, and research services to support the operation of cement plants, will avail the machinery to National Cement at no cost.

"It's already reached at the Port of Djibouti," he told Fortune.

National Cement has bought a biomass feeding system at the cost of 600,000 dollars.