Energy from Rice Residue - ARCHEA Develops Pilot Project in Cuba

The ARCHEA Group from Hessisch-Oldendorf is expanding its international activities with a pioneering project in Cuba. On the premises of a large rice production facility, a 250 kW biogas plant is to be established to generate decentralized energy for the factory from 60,000 tons of rice residue. In collaboration with the local partner, the University of Sancti Spíritus, ARCHEA is making a valuable contribution to reducing Cuba's dependence on crude oil and agricultural imports while providing ecologically and economically viable solutions to waste disposal and supply issues.

Cuba – an island nation evoking diverse associations: Hemingway, revolution, cigars, Caribbean flair, dream beaches, vintage cars, the legendary scenes in the film classic The Godfather II… In reality, the country stubbornly clung to socialism even after the fall of the Iron Curtain. However, the resumption of relations between former Cold War adversaries initiated a new phase of thawing between Cuba's leader Raoul Castro and US President Barack Obama since the end of 2014, raising hopes for many people and the economy alike.

The opening up of the country presents both exciting prospects for domestic businesses and foreign investors alike and exposes the country's development deficits more prominently. The energy supply is inadequate and prone to disruptions, mainly relying on fossil fuels, with Venezuela's almost free oil deliveries covering a significant portion of the demand for a long time. However, with Venezuela's plunge into a deepening economic crisis, the oil tap has gradually been turned off. Cuba's unilateral dependence on raw material imports thus becomes a glaring problem for modernizing the domestic industry. Potential growth opportunities arising from closer ties with the West could remain untapped. Therefore, Cuba aims to break free from this dependence and begins considering renewable alternatives. This is also due to increasing environmental issues: in agricultural cooperatives and state-owned enterprises, chemicals are indiscriminately used, while the government simultaneously heavily promotes industrialization. The consequences are severe: soil erosion, water, and air pollution are increasing significantly.

Despite favorable conditions, Cuban agriculture is considered one of the least productive in the Caribbean, with import quotas reaching up to 70-80% of consumed food, tying up foreign exchange reserves, much like the dependence on foreign raw materials. Therefore, Raoul Castro declared the increase in agricultural production as the main task. The utilization of fallow land is being promoted, and at the end of 2012, greater autonomy for agricultural cooperatives was decided, which henceforth have to forego state subsidies.

Cuba's opening up thus offers both exciting opportunities to renew the country's economy and significant challenges brought about by structural change. Against this background, the ARCHEA Group from Hessisch-Oldendorf established contacts with the University of Sancti Spíritus as early as 2012. A lively exchange developed from the first visit as part of the delegation trip of the Lower Saxony Minister of Agriculture, which eventually led to cooperation. Oliver Nacke, founder and CEO of ARCHEA, was impressed from the beginning by the comprehensive theoretical knowledge in the field of biogas among Cuban academics. "In my 20 years of work in the field, I have not seen anything comparable," Oliver Nacke states impressed. However, what the Cuban partners lack somewhat is the ability to transfer theoretical knowledge into practical applications. This is precisely the gap that ARCHEA fills with its long-standing experience in plant construction, with over 100 realized projects worldwide.

"In Cuba, there is a strong interest in green energy," explains Saskia Louwen, project-leading engineer at ARCHEA. She estimates the potential for electricity generation through biogas at a minimum of 500 MW. ARCHEA began preliminary work on a first pilot project last year. A plant with 250 kW is to be established on the premises of a large rice factory. Since resources for the cultivation of energy crops are lacking and the energy-rich rice straw remains as fertilizer in the fields after harvesting, a creative approach had to be found. ARCHEA developed the idea based on the doctoral thesis of Luz María Cotreras from the University of Sancti Spíritus to use residues from rice drying as substrate. The husks, broken rice grains, and straw residues are mixed with the manure from a nearby pig fattening farm, and gas is obtained through fermentation processes. The methane, in turn, drives a cogeneration plant. The heat and electrical energy generated can be used by the rice producer himself, including for the drying of rice grains. The goal is to achieve a high degree of self-sufficiency, ideally allowing the operation to completely eliminate the use of diesel generators for energy supply.

This example illustrates ARCHEA's approach to creating decentralized solutions for decentralized problems and thus enabling the economic operation of biogas plants independent of regional grid and feed-in systems.

The pilot plant is also intended to serve as a flagship project to familiarize Cubans with the benefits of biogas power plants. At the same time, the highly educated scientists at the university can gain valuable practical experience.

Despite the enthusiasm of ARCHEA employees and local partners, patience is required as an entrepreneur in Cuba. "Every bag of cement you need must be planned in advance in Cuba for a year," describes Saskia Louwen the pitfalls of centrally controlled planned economies. Also, bureaucracy often proves to be a hindrance. While foreign companies can now establish their own branches alongside joint ventures with local businesses, they are not allowed to recruit their own staff; instead, the state assigns skilled workers. Despite the administrative obstacles, ARCHEA is not demotivated. On the contrary, Saskia Louwen makes it clear: "We are determined to engage in biogas and thereby contribute to the economic and ecological transformation of the country."