In 1974 municipal solid waste incinerators (KVA/MVA) were introduced in Switzerland, which burns residential and industrial waste and the thermal energy produced is used. However, the resulting ashes and fly ash still needed to be deposited in special contained landfills. Primarily, the incineration is a thermal decomposition of the organic matter and the melting of the minerals and metals contained in the waste. A significant volume reduction is achieved by the incinerator.
Newer generations of incinerators are designed as so-called W2E plants. This refers to the optimization and improvement of the energy efficiency of the KVA/MVA, which improved the usage of generated heat, resulting from the incineration of waste to generate electricity and steam, as well as for the operation of district heating networks. As a result new W2E plants are built directly into the vicinity of the heat users in order to optimize the utilization of the heating potential. Potential locations are close to production companies with large steam requirements (e.g. paper mills) or large cities and municipalities with existing district heating infrastructure.
The downfall of W2E facilities is that they do not harvest the full potential of energy stored in the materials. Also, they are restrained to produce electricity and heat and therefore only economically feasible in surroundings were such products are needed. Another issue is that the flue gas cleaning is becoming more comprehensive and expensive as more new and different materials are introduced for incineration over time and regulations becomes more stringent.