As the technologies such as gasification improve to derive energy from waste, more waste-to-energy plants are emerging. Emerson’s Douglas Morris, a member of the alternative energy industry team, explores this trend in today’s guest post.
The old reality was that the alternative to burying municipal solid waste (MSW) in a landfill was to process it into refuse-derived fuel (RDF) and burn this fuel in an incinerator. This incinerator would provide heat to a boiler with could be used to produce power from a steam turbine.
The process is mature and there are many such power plants around the world that effectively produce small amounts of power for the grid. There is another waste processing method, though, that is gaining popularity: gasification.
Waste-to-energy (sometimes called energy from waste) plants come in two basic forms.
The simplified chart below shows the common pathways for these plants.
Although gasification has been around since early last century, it was never seen as an effective means to process MSW because of high capital and operating costs. As it turns out, the economics are improving. A number of companies around the world have already built plants or are looking to build them. There are a couple of advantages to using gasification.First, this process makes syngas, which can be used to produce a range of products and, unlike the waste from a traditional incinerator which has to be treated as hazardous, the waste (slag) from gasification is non-hazardous and can be used in construction materials. Additionally, gasifiers can tolerate a larger range of waste products and doesn’t require RDF as a feedstock.
As you know, politics and money always play a part in the development of newer industries. As governments continue to look for non-fossil based energy, they’ve put together a number of incentives, including loan guarantees and preferential tax treatment for which these plants qualify. As waste companies see increasing tipping fees and disposal taxes, they have an incentive to “give” their garbage away to a willing recipient. As a plant operator, it doesn’t get much better than free feedstock.
So as waste streams continue to grow around the world, and alternative sources of BTUs are needed, look for more waste-to-energy plants to be developed. If you want to learn more about the gasification end of this industry, check out a few of these companies: Enerkem, Solena Fuels, SGI Biopower, and AlterNRG.