Coffee effluent, next energy source?

COFFEE, that all-important drink many of us just cannot live without. It perks up our mornings and boosts our energy to help us last the day. Over a cup, we share stories with friends, plan projects with colleagues, and build relationships. We crave to try new blends just like we want to explore new places and adventures.

That’s not all. Our next cup of coffee might not simply be just a good drink. It could provide the answer to our search for the next energy source or the solution to climate change.

Training over the use of lamps fueled by biogas. Yalí de Jinotega, Nicaragua

Recent findings by the Energy from Coffee Wastewater, a project by UTZ Certified, indicate coffee mill discharge treatment could provide another means of generating energy. At the same time, utilisation of this effluent could reverse the effects of climate change and protect water resources.

The results of the project, which has been implemented in farms of different sizes, have been diverse, ranging from better indoor environment for families by replacing firewood with domestic gas stoves for cooking, to preventing local deforestation of native trees. Besides being able to treat essentially all water used in coffee processing, the project resulted in more than 50% savings in water utilised during coffee processing. 

Nicaraguan coffee farmer, F?tima Bland?n, cooking with biogas . (Yal?-, Jinotega, Nicaragua)

“Coffee production is only environmentally sustainable when water is used efficiently and polluted water from the wet-mill process is treated. Local ecosystems do not have the capacity to clean the large amounts of contaminated fluids,” said Han De Groot, executive director at UTZ Certified, a label and programme for sustainable farming of agricultural products launched in 2002, for coffee, tea, cocoa, and other products.  “Rural communities and coffee production depend intrinsically on a ready supply of fresh water. So if we want to talk about coffee produced in a sustainable manner then wastewater must be treated when released into the environment.”

Further, the Energy from the Coffee Wastewater project has so far generated a significant amount of biogas to power households and coffee mills. It was also able to prevent the release of greenhouse-gas emissions.

Launched in 2010, the Energy from Coffee Wastewater project aims to address environmental and health problems caused by the wastewater produced in the coffee industry. The project involved installation of tailor-made coffee wastewater treatment systems and solid-waste treatment mechanisms in eight coffee farms in Nicaragua, ten in Honduras and one in Guatemala.

Encouraged by favourable results impacting more than 5,000 people in the region, UTZ Certified plans to replicate the initiative in Asia and Africa.

Latin America accounts for about 70% of the world’s coffee; it is also where 31% of the world’s freshwater resources are located. Coffee production generates a huge amount of effluent which is made up of organic matter including sugars, cellulose, caffeine and pectic substances that lower the amount of oxygen in water and soil, consequently affecting not only marine life but also downstream communities. The organic waste and high toxicity affect the soil and generate significant amounts of greenhouse-gas emissions, in particular methane, which contribute considerably to climate change.