The generation of electricity from renewable sources of energy, in particular sugar cane biomass, is today a strategic priority for Cuba and is part of the Cuba green energy development program.
Sugar cane, an energy crop, is the main raw material of the AZCUBA Group, which produces different types of sugar (crude oil, refining, white direct and ecological) and 20 other commodities derived from cane which include: electricity, alcohol, animal feed and bioproducts.
The sugar cane crushing process leaves behind a raw material called ‘bagasse’. This raw material can, to a large extent, replace fossil fuel given the high calorific value it has. It is how the country will meet the goals of energy matrix change by using energy from renewable sources.
As a result, the electric energy co-generation programme of the AZCUBA Group plans to use sugar cane bagasse as the main fuel at 25 sugar mills. Fourteen of these sugar mills will contribute with the bagasse from their harvest.
Today, the installed capacity available amounts to 468 MW. The power generation project based on sugar cane biomass contemplates a total of 950 MW of electric power to be installed in the 25 biopower units by the year 2030.
One part of the electric power produced will ensure the operation of the sugar mill. The surplus of the manufacturing process will be sold to the National Electric Union (UNE) system resulting in a considerable reduction of financing needed for the purchase of fuel. The project also includes the requirement of new land to be expanded for sugar cane cultivation.
As a principle, the new bioelectrics will be built adjacent to the sugar mills which were enlisted in the program. These plants will operate on 100% renewable fuel sourced from sugar cane bagasse, agricultural residues (cane straw) and condensate pure steam coming from pre evaporators.
Selected technology will lead to improvements to the agro ecosystem by incorporating residual ash from the generation of steam, (which has high content of potassium, wet form as fertilizer), to the sugar cane areas. It also ensures the conservation and best use of water resources, to condense the steam from the turbine, closing the cycle in turbo generators of extraction condensing steam.
The program consists of the construction, assembly and start up of 25 bioelectrical (20, 35, 50 and 60 MW) in all the provinces of the Cuban archipelago except for the provinces of Pinal del Rio, Havana, and the special municipality of Isle of Youth. Foreign investment for this program with the AZCUBA group is focused on the 20 pending contract bioelectrical projects currently available. The bioelectric plant supplies the sugar mill with the exhaust steam from the turbo-generators for the sugar manufacturing process, as well as the electric power it may need. The surplus power from the sugar making process will be sold to the Domestic Power Union.
This program can be found in Cuba’s Portfolio of Investment opportunities open to foreign investment under the Cuban Law of Foreign Investment.
Sugar cane is one of the crops with great capacity to turn solar energy into biomass. If only bagasse and trash were taken into account, the sugar cane fields store about the equivalent to one tonne of oil per each tonne of sugar that may be produced. To produce one tonne of sugar, ten tonnes of sugar cane are needed.
The environmental impact of the co-generation of the Electricity Program includes the harvest of marabou as fuel, which will help make more agricultural land available for the planting of food and other intended uses the Ministry of Agriculture and Planning Institute of Physics, as well as the use of excess sugarcane biomass from other nearby stations.
Currently the sugar industry, with a gross generation of 750 GWh, provides 81 percent of energy by renewable energy sources in Cuba and represents 3.5% of the national energy matrix. The foreseen results of this program will include the increase in agricultural performance, renewal and extension of areas for agriculture and the increase of sugarcane biomass generation.