Potential for ORC application in the Portuguese manufacturing industry

• Author(s): Marques, Mariana Walter de Freitas Pereira
• Date: 2014
• Persistent ID: http://hdl.handle.net/10362/13041
• Origin: Repositório Institucional da UNL
• Subject(s): ORC; Waste heat recovery; Manufacture industry; Energy efficiency target
• Document Type: Master Thesis
• Language: English
• Advisor(s): Melo, João

Description

Dissertação para obtenção do Grau de Mestre em Engenharia do Ambiente, perfil Gestão e Sistemas Ambientais The European Directive on Energy Efficiency (Directive 2012/27/EU) entered into force in 2012 to translate the EU ―20-20-20‖ Efficiency Target into binding legislation. Each Member State was obligated to set an indicative national energy efficiency target and to achieve a certain amount of final energy savings by 2016. The second Portuguese National Action Plan for Energy Efficiency (PNAEE 2016) defines a target of 8.2% for savings on final energy consumption by 2016. Savings in Industry account for 24% of the target, but less than half of it was executed through the former Plan (PNAEE 2008-2015), by the end of 2010. Worthwhile energy saving opportunities remains such as the recovery of the great amounts of wasted heat in industrial processes. Some technologies have been proposed to generate electricity from low temperature heat sources, among which the Organic Rankine Cycle (ORC). The present work assesses the wasted heat in some sectors of the Portuguese manufacture industry and the potential to implement ORC systems. The methodology developed was based on the analysis of 116 industrial plants through energy audits and other documents. The 50 plants that revealed potential for ORC implementation were the base for estimations and represent 16% of the manufacture industry total energy consumption in 2010. The national support schemes for power generation from renewable resources and cogeneration do not contemplate specifically the electricity production through waste heat recovery. Therefore, the country lacks on an appropriate framework. This study provides a preliminary assessment of the benefits reachable through waste heat-to-power generation and intends to help focus future efforts by the government on the inclusion of ORC in national strategies as an energy efficiency measure in Industry. A total of 8 sectors were analysed but only 4 are included in the final universe: Ceramic, Cement, Basic metals and Wood & Cork. For these, ORC units of 48 kWe to 3.3 MWe installed power are feasible, showing payback times typically between 2 and 6 years. For an estimated total investment of 104 M€ in ORC systems in the Ceramic, Cement, Basic metals and Wood & Cork industries, about 37 MWe installable power could mean executing 5.2 to 6.6% of the Portuguese 2016 Target of savings on Final Energy consumption in Industry, with associated avoided emissions of 132 kt CO2e/year.