High temperature heat pumps for efficient utilisation of low temperature surplus heat

Heat pumps offer the unique possibility to utilise low temperature heat source efficiently to supply thermal energy at a usable temperature level by applying only a fractional amount of renewable electricity. Current temperature limits for industrial heat pumps are however around 80'C, which is limiting industrial and large scale applications. The aim of HeatUp is to: i) extend this limitation beyond 100'C and up to 200'C by using natural working fluids like butane, ammonia and water, ii) develop novel concepts for high temperature heat pumps at industrial scale for the Norwegian and European industry. The focus is tuned towards utilization and upgrade of industrial surplus heat, a significant and valuable energy sources. These sources are nowadays unused because of the lack of suitable high temperature heat pumps and long return of investment times. Heat pump technologies developed in shall reduce the dependency on fossil fuels, as well as contributing towards a carbon-neutral green future. The project is focusing on the application of robust and compact key components and efficient heat pump cascade systems utilizing environmentally friendly refrigerants. A main focus in 2015 and 2016 was development of a novel compression technology based on cost effective standard automotive turbo-chargers. It is expected that this compressor technology offers a cost-effective alternative and can provide thermal process energy up to 200'C. A proof of concept test in cooperation with the industrial partners of the project was performed, indicating promising results. Further development will be performed in the spin-off project DryF, financed by EUs Horizon2020 programme based on a selected industrial case, and as a part of FME HighEFF. In 2016-2017 a new concept for a cascade heat pump based on hydrocarbon working fluids for the production of pressurized hot water was designed, build and commissioned. Tests show a great potential for effectively upgrade waste heat from e.g. 20'C to up to 120'C. Testing design and development is done in close collaboration with the supplier industry and end-user industry. Results are published by the PhD student. The potential of hybrid heat pumps (with ammonia water mixture) was evaluated for several industrial cases to provide thermal energy up to 120'C, while utilizing the temperature glide for thermal adaptation to the heat source and sink. HeatUp educates through summer-, project-, master- and PHD-students. HeatUp has organized a high temperature heat pump workshop together with DTU and DTI. The workshop covered: market potential - developments ? challenges; ongoing research and development projects; heat pump developments - market ready products; case studies including realized projects. The industrial partners of HeatUp are representing the main Norwegian industry sectors: Statoil ASA (oil and gas), Statkraft Varme AS (district heating), Hydro Aluminum (metal industry), Vedde AS (aquaculture) and Mars Inc. (feed and food). The supply industry is represented by inkind contributions from Epcon Evaporation Technology AS, Cadio AS og Hybrid Energy. SINTEF Energy Research is the project responsible for HeatUP. Contact: Christian.Schlemminger@sintef.no and Petter.Neksa@sintef.no More information: http://www.sintef.no/projectweb/heatup/

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Heat pumping is the third largest source of renewable energy in Norway, surpassed only by hydropower and bioenergy. In 2007 a revised projection for 2020 predicted an additional profitable potential of 10-14 TWh. SINTEF and NTNU have played a major role internationally in the development of presently commercially available hot water heat pumps with natural working fluids and this technology is now in the growth phase internationally. In order to transfer the recent rapid growth of low temperature heat pumping technologies to higher temperature applications, including industrial steam production, new technology is needed. HeatUP will focus on the utilisation and upgrading of industrial surplus heat. There are two main reasons for this: One is the above mentioned availability of low cost low temperature heat. The second reason is the high number of annual operation hours of industrial plants, often approaching 8000 operating hours per year. This high utilisation of installed capacity will increase the likelihood of acceptable payback time for heat pumping investments. A number of Norwegian process industries require large amounts of heat in the temp. range 80-250°C, while surplus heat is often available in the lower temperature range of 30-40ºC. HeatUp will address high temperature heat pumping in these industries, where the more specific knowledge needs have been identified: -New concepts for high temp., high capacity heat pumps for steam production and high temp. (pressurised) water heating, e.g. district heating or service water. How to design such systems and how to adapt them into practical use. -Knowledge about how to design robust and compact key components, efficient heat pump cascades for HTHPs utilising environmentally friendly working fluids. -Increased general knowledge and awareness on heat pumping technology and surplus heat utilisation. It has been pointed out by Enova that lack of knowledge is a major barrier to improved energy efficiency in Norway.