The BELCOGEN bagasse plant in Orange Walk, Belize.
Central America is an economically and ecologically diverse region with growing energy needs and unique vulnerabilities to climate change. Boosting investment in renewable energy is a key way that the region can protect its ecologically sensitive areas while achieving reliable access to clean energy for its population. In Central America, the top four renewable energy sources are geothermal, hydroelectricity, biomass, and wind. The relative importance of each renewable resource is different for each country depending on the geographical and geological situation. The Worldwatch Institute has recently begun work aimed at creating a favorable policy and investment environment for renewable energy in Central America.
Globally, the electricity sector is one of largest and fastest-growing consumers of energy. It is therefore important to consider the role of state and private utility companies in transitioning Central America to renewable energy sources. One of these companies, BELCOGEN, a subsidiary of state owned Belize Electricity Ltd (BEL), has received enormous amounts of attention and praise due to its recent investment in a 31.5 megawatt (MW) biomass power plant fueled by bagasse. BEL invested US$63 million to create BELCOGEN and the bagasse project. The price tag has officially made the deal the largest private investment ever made in Belize. Originally, the project was scheduled to be completed in 2007 and the investment was much lower; however, the necessary investment grew as the scheduled date of completion was postponed, and the project was finally completed in 2009. The plant runs on a combination of 92 percent bagasse and 8 percent heavy fuel oil. BELCOGEN is contractually obligated to sell at least 106 gigawatt-hours (GWh) to BEL for the first year of operation, making the company the source of at least 20 percent of Belize’s national energy demand. The rest of the energy produced (up to 44GWh) will be sold to Belize Sugar Industries Limited (BSI).
Electricity from biomass is produced through combustion of the biomass product. The heat from the combustion process is used to produce steam which powers a generating turbine. Bagasse is a type of biomass and is produced as a byproduct of the process of extracting the juice from sugarcane. Bagasse power plants are typically connected directly to a sugar factory. The BELCOGEN project is connected to the Tower Hill Sugar Plant. This allows for the seamless processing of sugar from sugarcane and the subsequent storage of “wet bagasse.” Wet bagasse is the initial product after sugar has been extracted. It is stored prior to use for electricity generation because moisture in the fibrous material can damage the energy production potential of the power plant. Once enough moisture has evaporated, the material is called “dry bagasse”. At this point, the power plant can either use the bagasse directly to create steam, or the dry bagasse can be used to create charcoal. Bagasse charcoal is made by placing dry bagasse in a kiln where it is further processed using a method of high temperatures and low oxygen. The low oxygen environment ensures that the bagasse does not combust and the high temperatures drive off any other unwanted particles. Bagasse charcoal can be sold for individual household use.
Typically, bagasse power plants emit many types of greenhouse gases and particulate matter, primarily due to incomplete combustion if there is still excessive moisture content in the bagasse and a lack of adequate operational control. However, the BELCOGEN plant operates through complete combustion and recent high standards, set by the World Bank and incorporated into the construction of the plant, will result in lower emissions. These standards include electrostatic precipitators to pull particulate matter from the exhaust; instead of smoke being produced, the plant’s singular chimney will emit a clear haze.
In addition to reducing greenhouse gas emissions, the plant is proving to be a boon for the domestic economy. Belize currently imports a large share of the electricity for its national grid as well as all of its fossil fuels from neighboring Mexico, a significant drain on national financial resources. With less money leaving the country, Belize can invest more domestically and spur sustainable development within its borders. Decreased dependence on fossil fuels will also provide some relief from the price fluctuations of oil on the global market. These fluctuations make it increasingly difficult for the nation to move towards more renewable energy. Major investments in renewable energy, like the BELCOGEN bagasse plant, are essential for transitioning Central America to more clean and local sources of energy.