Image Credit: Municipal solid waste in the furnace
Production of electricity from waste has the potential of providing up to 83.8 TeraWatt hours (TWh), which is about 20% of the electricity needed in Africa by 2025. This is according to a study co-authored by the European Commission Joint Research Centre (JRC). However, this requires stringent waste management policies to be put in place, and today Africa lacks the adequate infrastructure needed to install these environmentally friendly methods.
Like some other parts of the world, most of the waste in Africa is burned without tapping the potential of gases (which usually end in pollution) or dumped in landfills without protecting groundwater. Many of the developed countries that have a high percentage of waste to energy recovery, have strict emissions laws that regulate waste handling.
Waste in Africa, according to JRC, can be used to produce energy in two ways. The first is using Waste-to-energy (WTE) incineration plants where the trash is burnt to produce steam that turns turbines. The report notes that these are few in this part of the world because of the high initial costs of establishment. Strict measures are needed to ensure the plants do not pollute the environment via toxic by-products.
Although most of Africa buries or dumps waste that when decomposing releases methane and carbon dioxide gases naturally. These gases can be captured for heat or burnt in gas turbines, internal combustion engines, and steam boilers to produce electricity. This is the second method.
Waste energy recovery could act as one stone killing two birds because it provides power, and at the same time helps deal with the increasing waste problem in Africa. The continent is expecting incredible growth in population and urbanization, which is to be accompanied with production of more waste. The reports points out that energy recovery from waste could help alleviate energy poverty in countries such as Central African Republic, Burundi, Guinea-Bissau, Mali, Sierra Leone, Rwanda and Somalia, which have poor access to electricity and low electricity consumption per capita.
The potential could be much higher since the 20% figure is based on urban waste calculations alone according to the report. Most of waste around the world is concentrated around urban centers.
A few projects already underway
Just recently, Cleanleap wrote about Africa's first and largest Anaerobic Digester (AD) which will generate 2.4 MW of installed power that will be channeled to Kenya's national electricity grid. It first converts biomass waste (organic waste being sourced from nearby farms) to biogas and then the biogas is burned to produce electricity and heat. In addition to using 50,000 tones of organic crop waste each year, it will produce 35,000 tones of nitrogen-rich matter as a by-product natural fertilizer. The first phase of the project is now complete.
My colleague also recently wrote about an Ethiopia's 50-year-old towering mountain of waste Koshe being converted into power. Koshe Waste-to-Energy facility will generate 50 megawatts of clean energy by burning 350,000 tones of waste annually. It will help deal with the waste menace. Construction of the factory started last year and was to complete in 18 months.
The Bill and Melinda Gates Foundation are also partnering to see the first Omni Processor factory pilot project that converts sewage into drinking water and power. The first factory will be based in Senegal and, although it is fronted as a project to mainly reinvent the toilet, it will produce 150W of power and the success of the pilot project would prove that the solution can be duplicated all over developing countries. It involves boiling of sludge to high temperatures to produce steam, which is then used to run steam engines. Construction of the factory begun last year.
These are just but a few of the thousands, but yet insufficient, projects being pursued to produce power from waste.
The issue of power shortages cannot be re-emphasized and introduction of off-grid solutions is seen as helpful towards increasing power access. In short, in addition to bringing a revolution to how we generate power so much needed in Africa, waste-to-energy projects will also help deal with sanitation problem in developing countries, one of the largest problems facing many of these nations and which is still responsible for many health problems.