Background Despite efforts to increase the recycling of urban waste, a non-recyclable fraction is still disposed of in landfills. This fraction contributes to greenhouse gas emissions, due to the production of methane (CH4) and carbon dioxide (CO2) during waste deterioration. However, this non-recyclable fraction does have a potential use: electricity can be generated from it by gasification. This technique converts the carbon-based content of waste streams into carbon monoxide and hydrogen, by reacting it at high temperatures with a controlled amount of oxygen and/or steam. The resulting ‘synthesis gas’ can be used as a fuel. Using gasification to extract renewable energy from organic waste is a much more environmentally-friendly management option than sending it to landfill. The thermal utilisation of non-hazardous bio-residues and waste streams could be a key element in an integrated waste management concept to satisfy the EU’s Thematic Strategy on Waste (COM (2005)666 Final). Objectives The objective of the LIFE ENERGY-WASTE project was to demonstrate an advanced gasification concept for the energy exploitation of the non-recyclable stream in an urban waste recycling factory. It also aimed to show that this approach can reduce the overall greenhouse gas emissions from urban waste streams. In particular, the project aimed to develop and implement a specific demonstration logistics management scheme in the coordinating beneficiary’s recycling factory, which has a capacity of 100 000 tonnes/yr. Results The LIFE ENERGY-WASTE project designed, installed and operated a gasification unit in a waste recycling factory. This was used to demonstrate a gasification concept for energy exploitation, through the production of refuse-derived fuel (RDF) and solid recovered fuel (SRF), and also showed that its application could reduce greenhouse gas emissions. The environmental impact, sustainability and replication potential of the gasification approach were assessed and found to be positive. The project’s main innovations were to integrate state-of-the-art technologies (Municipal Solid Waste (MSW) recycling, waste gasification and potentially a biogas power plant), and the preparation of a classified SRF from non-recyclable waste and its subsequent utilisation with thermal treatment (gasification technology). The project documented the relevant legal framework in Europe, the current waste management technologies used, and the potential waste streams for RDF/SRF production in Greece and the region of Central Macedonia. A network of stakeholders involved in various stages of the RDF/SRF utilisation chain was established. The RDF/SRF from a WATT (formerly EPANA) facility was prepared, sampled and characterised according to the European CEN/TC 343 standard. After identification of the main material streams generated in the treatment process at the WATT Material Recovery Facility (MRF) at Ano Liossia, it was estimated that 85% of the remainder (RDF) had thermal capacity. Tests were performed to identify the most efficient form of fuel (e.g. fluff, pellets, shredded). As shredding proved the best approach for RDF production, a shredder was purchased. Additional tests were done to determine the sampling procedure, including specifics on the minimum and most effective sample and increment sizes. Detailed analyses of the collected samples for all the obligatory parameters (CEN/TC 343), and some additional ones, were performed for fuel characterisation purposes. The design stage of the pilot gasification unit included analysis of process thermodynamics, mass and energy balances, equipment sizing, process modelling, and laboratory testing. As different parts of the gasifier were constructed and tested, mistakes were corrected and modifications made. After the full installation, the whole gasification unit was cold and hot tested and final modifications implemented. Pilot tests were performed first with willow wood pellets, and then with RDF from the WATT MRF after it had been made into pellets by associated beneficiary CERTH at its institute in Ptolemais. The gasifier's efficiency was estimated with the use of two different indicators, Cold Gas Efficiency (CGE) and Carbon Conversion Efficiency (CCE), and by calculating the mass and energy balances. Furthermore, the gasifier's thermal energy efficiency and environmental performance were assessed and the scale-up potential was examined. The energy acquired from the utilisation of RDF is almost half the energy required for the gasification process to proceed and maintain a steady temperature at the range of 750-800°C. Given the cost, it is imperative to scale up the gasification pilot unit in order to acquire better financial results. A Life Cycle Assessment (LCA) established the potential environmental impacts of the gasification technology, and a techno-economic study compared gasification and incineration specifically for RDF from the WATT facility. The RDF production potential in Greece was also analysed, while two sets of scenarios (involving different fuel qualities, electricity prices and gate fees) were considered. It was found that gasification technology is financially feasible in large-scale plants, and that drying the fuel can be a more profitable solution (providing better returns on the same investment). For low-quality fuels and a gate fee up to €40/tonne, all investments can be profitable for electricity prices above €95/MWh, while for high-quality fuels all investments are profitable for €85/MWh of electricity. The project implemented many dissemination activities, particularly towards its end when results from the pilot gasification unit could be presented, including talks at conferences, scientific papers and exploitation/replication guides. Environmental benefits from generating electricity from the non-recyclable fraction of urban waste include less waste disposed at landfills, and reduced CH4 and CO2 emissions (the main greenhouse gases arising from landfills). Furthermore, the project promoted the utilisation of urban waste for electricity generation as a more environmentally-friendly waste management option within the framework of the Community Waste Strategy (COM (96) 399 Final), and in line with the Landfill Directive (1999/31/EC). Further information on the project can be found in the project's layman report and After-LIFE Communication Plan (see "Read more" section).