Energy-Use Minimisation via High Performance Heat-Power-Cooling Conversion and Integration: A Holistic Molecules to Technologies to Systems Approach

Lead Research Organisation: Imperial College London
Department Name: Department of Chemical Engineering

Abstract

A 4-year multidisciplinary project aimed at minimising primary-energy use in UK industry is proposed, concerned with next-generation technological solutions, identifying the challenges, and assessing the opportunities and benefits (to different stakeholders) resulting from their optimal implementation. Around 20 companies from component manufacturers to industrial end-users have expressed an interest in supporting this project. With this industrial support, the team has the necessary access and is in a prime position to deliver real impact, culminating in the practical demonstration of these solutions.

The proposed project is concerned with specific advancements to two selected energy-conversion technologies with integrated energy-storage capabilities, one for each of: 1) heat-to-power with organic Rankine cycle (ORC) devices; and 2) heat-to-cooling with absorption refrigeration (AR) devices. These technological solutions are capable of recovering and utilising thermal energy from a diverse range of sources in industrial applications. The heat input can come from highly efficient distributed combined heat & power (CHP) units, conventional or renewable sources (solar, geothermal, biomass/gas), or be wasted from industrial processes. With regards to the latter, at least 17% of all UK industrial energy-use is estimated as being wasted as heat, of which only 17% is considered economically recoverable with currently available technology. The successful implementation of these technologies would increase the potential for waste-heat utilisation by a factor of 3.5, from 17% with current technologies to close to 60%.

The in-built, by design, capacity for low-cost thermal storage acts to buffer energy or temperature fluctuations inherent to most real heat sources, allowing smaller conversion devices (for the same average input) and more efficient operation of those devices closer to their design points for longer periods. This will greatly improve the economic proposition of implementing these conversion solutions by simultaneously reducing capital and maintenance costs, and improving performance.

The technologies of interest are promising but are not economically viable currently in the vast majority of applications with >5-20 year paybacks at best. The project involves targeting and resolving pre-identified 'bottleneck' aspects of each technology that can enable step-improvements in maximising performance per unit capital cost. The goal is to enable the widespread uptake of these technologies and their optimal integration with existing energy systems and energy-efficiency strategies, leading to drastic increases performance while lowering costs, thus reducing payback to 3-5 years. It is intended that technological step-changes will be attained by unlocking the synergistic potential of optimised, application-tailored fluids for high efficiency and power, and of innovative components including advanced heat-exchanger configurations and architectures in order to increase thermal transport while simultaneously reducing component size and cost. Important system-level components are included in the project, whose objective is to assess the impact of incorporating these systems in targeted industrial settings, examine technoeconomic feasibility, and identify opportunities relating to optimal integration, control and operation to maximise in-use performance. A dynamic, interactive whole-energy-integration design and assessment platform will be developed to accelerate the implementation of the technological advances, feeding into specific case-studies and facilitating direct recommendations to industry.

Only two international research teams are capable of developing the necessary tools that combine multiscale state-of-the-art molecular thermodynamic theories for fluids, detailed energy-conversion ORC and AR models, and incorporating these into whole-energy-system optimisation platforms. This is truly a world-leading development.

Planned Impact

This project aims to demonstrate next-generation heat to electricity or cooling conversion technologies suitable for industrial applications. Step-changes are proposed in the evolution of two suitable technologies, ORC and DAR devices, that aim to improve performance and also, crucially, to decrease cost and increase flexibility. Considering that ~17% of UK industry energy-use is rejected to the environment in the form of wasted heat, the successful implementation of the outcomes of the project has the significant potential to decrease primary-energy demand, by improving the utilisation of waste-heat by a factor of 3.5, from 17% with current technologies to 60%. The proposed solutions are also capable of recovering and utilising thermal energy from distributed CHP units, and other conventional or renewable sources (biomass/gas, geothermal, solar). The solutions promise payback as low as 2-3 years, significantly lowering the current barriers to uptake. If the identified waste-heat from suitable sources is converted to power, 2-3% of all UK electricity generation could be displaced, replacing 1 average UK coal-fired power station or 3 new CCGT plants.

Value change will be created that will bring benefits to the academic community and stakeholders (e.g. simulation-guided novel fluids), the lead users and manufacturers (new heat-exchanger configurations with high power-density, reduced size and cost) and the end-users (reduced energy demand, independence, competitive advantage), and also more wide-ranging societal benefits in terms of enhancing economic, environmental and social sustainability.

The project has the potential to lead to breakthrough energy-utilisation solutions, transforming industrial practices, leading to step-changes in energy-input reductions to industrial processes, emission reductions and significantly increased resilience to uncertainty in primary-energy supply. It will lead to transformative improvements in materials and equipment design and process operation with substantial efficiency gains, and give the UK a significant lead in the design, development, manufacture, installation, operation and knowhow of these technologies and their implementation.

A detailed plan with regards to impact on knowledge, the economy, society and people has been prepared, based on the experience of the investigators in similar projects, including, for example, an Industry Engagement Programme (IEP) aimed specifically at interacting with our partner companies, identifying new interested industrial end-users (and component manufacturers, or installers), and interacting with partners during the case-studies. Furthermore, the team has close links with, and support from, a large number of industrial partners and smaller spin-out companies who will benefit greatly from the results of the proposed research, either directly from the findings or secondments and exchanges. We also have start-up/entrepreneurship experience, foster close links with DECC, DCLG, R&D and technology translation initiatives such as the Technology Partnership (TTP) and Carbon Trust, have been part of numerous non-academic networks, and have a strong technology transfer track record, e.g.: PSE, Hexxcell, Thermofluidics.

This project will supply the next generation of highly skilled energy technology and systems researchers and entrepreneurs, delivering a range of societal impacts underpinned by the enhanced sustainability of UK industrial processes: 1) sustainable and more-efficient processes, energy, power and manufacturing due to superior equipment design and processes operation resulting in reduced energy requirements manufacturing, reduced downtime, waste and primary energy demand; 2) new technologies and routes, via both power and cooling including storage, for enhanced energy efficiency and low emissions towards a sustainable and decarbonised energy society; as well as 3) engaging policy-related contacts and young people/public engagements.

Publications

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Description By extending the CAMD-ORC framework to include the design of refrigerant working fluid in addition to hydrocarbons, new insights have been gained on the type of working fluid that should be used for a given waste heat recovery application. For example, the findings from this work reveal that refrigerants are particularly suitable for low temperature heat source, while hydrocarbons tend to give better performance (in terms of power output) for medium to high temperature heat sources. Further studies will expand the scope of the current work to include large spectrum refrigerants.
Exploitation Route The findings from this research can serve as a guide for design engineers, particularly for the selection of optimal working fluid for a given waste heat recovery application. As the proposed framework has already been published, it can be used by both academics and industrial practitioners to facilitate the search for the next-generation organic Rankine cycle systems that are economically viable. Further research can be carried out to widen the scope of the proposed framework, e.g. addition of new molecular groups to allow the design of novel and existing working fluids, including but not limited to hydrocarbons such as ether, alcohol etc. Other cycle configuration can also be exploited, e.g. trans-critical cycles.
Sectors Aerospace, Defence and Marine,Agriculture, Food and Drink,Communities and Social Services/Policy,Construction,Energy,Environment,Manufacturing, including Industrial Biotechology,Retail,Transport

 
Title Expander testing facility 
Description An experimental appartus has been developed within the Clean Energy Processes (CEP) Laboratory to test various expansion machines (positive-displacement and turbo expanders) under varying conditions. The CEP expander testing facility is made of a two-stage intercooled reciprocating compressor, a heat-rejection heat exchanger, the expander test section, and a heat-addition heat exchanger. 
Type Of Material Improvements to research infrastructure 
Year Produced 2019 
Provided To Others? No  
Impact This apparatus can be used (i) to investigate the performance of various positive-displacement and turbo expanders whilst operating with different working fluids, namely light gases (e.g., Nitrogen) and refrigerants (e.g., R245fa), (ii) to study possible components degradation, and (iii) to investigate two-phase expansion. 
 
Title Organic Rankine Cycle (ORC) test rig 
Description The experimental apparatus is a small-scale 1-kWe ORC test rig aiming at investigating the part-load performance of an ORC engine with multiple working fluids and varying architectures. 
Type Of Material Improvements to research infrastructure 
Year Produced 2019 
Provided To Others? No  
Impact The testing facility is highly adjustable: all components can easily be replaced. It will not only be used to validate modelling tools developed in the laboratory but also to test innovative components, novel fluids and advanced control strategies. 
 
Title Building heat recovery investment model. 
Description The model allows the user to input the building electrical and heating demand and site constraints. An optimisation is then performed to find out the optimum combination of heat recovery technologies according to a specific indicator input by the user (e.g. 5-year NPV). The model output the best combination of heat recovery technologies and the optimal way they should be controlled. 
Type Of Material Computer model/algorithm 
Year Produced 2016 
Provided To Others? No  
Impact The model was applied to quantify and indicate the best investment in heat recovery technology to 2 very large companies. 
 
Title CAMD-ORC framework model 
Description The CAMD-ORC framework is a systematic method for optimal design of organic Rankine cycle systems for waste heat recovery applications. The framework integrates working fluid design/selection and cycle optimisation into a single stage, thus eliminating the pre-emptive and subjective screening of working fluid that is associated with the two-level design method. The framework has been extended to account for the design of refrigerate working fluids. 
Type Of Material Computer model/algorithm 
Year Produced 2017 
Provided To Others? Yes  
Impact The proposed research method offers a unique approach for the simultaneous design of working fluid and organic Rankine cycle systems, facilitating the selection of an economically-viable systems. The findings from this work have been published in conference proceedings and journal papers. 
 
Title Database of ORC units 
Description A model indicating the costs (including installation costs), technical characteristics, and performance curves of different ORC unit 
Type Of Material Database/Collection of data 
Year Produced 2017 
Provided To Others? Yes  
Impact The technology database represents the building block of the model described in the previous part. 
 
Title Lumped-mass model for simulation and optimisation of reciprocating-piston devices 
Description The thermodynamic model that has been developed is of a reciprocating-piston device, which could be a compressor or expander. By calculating the fluid flows and various loss mechanisms in the device, it allows predictions to be made of the performance of the system on the basis of readily-available geometric measurements, and draws on physical principles rather than relying on extensive experimental data for capturing the various phenomena that take place. It therefore offers a useful design tool for researchers wishing to understand device performance and manufacturers seeking to design and optimise new and existing systems. The principles and equations underpinning the model have been published in several conference articles and a journal paper (doi:10.1016/j.apenergy.2018.12.086). There are no legal or ethical constraints affecting the sharing of the model. 
Type Of Material Computer model/algorithm 
Year Produced 2017 
Provided To Others? Yes  
Impact The model has been used in two main areas: piston expanders for organic Rankine cycle (ORC) engines, and compressors for compressed air energy storage. In the former, piston expanders are not yet a mature technology for ORC applications, so there is very little experimental data available. The model therefore allows exploratory studies to be conducted, for example to assess different working fluids or to compare piston expanders against other devices. A journal paper has been published on off-design performance of an ORC system with a piston expander, drawing on the ability of the model to provide predictions at on- and off-design conditions. Multiple conference papers have been presented, including on the model itself, on piston expander performance maps, comparing piston expanders against screw expanders, and against turbines, and comparing ORC and CO2 cycles. 
 
Title Thermo-economic models for ORC and CO2 based cycle systems 
Description Thermodynamic and economic models of both ORC and CO2 based cycle have been established in Matlab code and validated by the data in previous literatures. Various cycle configurations are considered and both piston reciprocating expander and radial-inflow turbine are employed. The models allow comparison of the two types of cycles and can generate techno-economic performance maps. 
Type Of Material Computer model/algorithm 
Year Produced 2019 
Provided To Others? Yes  
Impact The models established allow comparison of ORC and CO2 based cycle system for different heat source conditions and can generate techno-economic performance maps to provide suggestions for system preliminary design. 
 
Description CFD of Reciprocating Piston Machines - Professor Pietro De Palma 
Organisation Polytechnic University of Bari
Country Italy 
Sector Academic/University 
PI Contribution We have made available a series of experimentally validated CFD codes developed during the Pumped Thermal Electricity Storage (PTES) project, as well as personnel to support the collaborative activities of this interaction. Specifically, Dr. Paul Sapin is working closely with Mr. Giuseppe Rotolo who is visiting us for 6-months from Professor Pietro De Palma's group at Politecnico di Bari.
Collaborator Contribution Professor De Palma is an expert in CFD and in particular in conjugate-heat-transfer problems in complex geometries. We have began a collaboration on applications of these advanced tools to reciprocating piston machines. We are currently hosting Mr. Giuseppe Rotolo, a student from Professor Pietro De Palma's group, who is working with personnel from my group to extend our gas spring CFD tools. Professor De Palma recently (mid-March 2017) visited us, gave an open cross-Departmental seminar on this work, and had update meetings with the team of researchers that are working in this area.
Impact Advanced CFD tools in OpenFOAM with an extended ability to solve the full conjugate thermal problem inside reciprocating piston machines. The collaboration has only just started so these activities are on-going.
Start Year 2017
 
Description Comparison of ORC and CO2 based cycle systems 
Organisation Tsinghua University China
Country China 
Sector Academic/University 
PI Contribution As part of this research effort our team established thermo-economic models for different cycles and expanders. This research is pertinent for the comparison of CO2-cycle and ORC with both piston reciprocating expanders and radial-inflow turbines for various heat source conditions.
Collaborator Contribution One visiting postdoc from the collaborating institution came in 2018 and established models for CO2 based cycles and radial-inflow turbine.
Impact 1 x conference paper accepted: (1) 5th Sustainable Thermal Energy Management International Conference. 2 x journal paper in preparation (aimed submission March 2019.)
Start Year 2018
 
Description Integration of radial inflow turbine model into an existing CAMD-ORC framework. 
Organisation University of Cambridge
Country United Kingdom 
Sector Academic/University 
PI Contribution The team at Imperial College London carried out the implementation of radial inflow turbine performance map into an existing CAMD-ORC framework. In addition, an ORC system optimisation under time-varying heat source conditions has been completed. The findings from this research is expected to be published in the proceedings of the upcoming ECOS 2019 conference.
Collaborator Contribution The team at University of Cambridge carried out the development and validation of radial inflow turbine model.
Impact One (1) conference paper to be presented at the 32nd International Conference on Efficiency, Cost, Optimisation, Simulation and Environmental Impact of Energy Systems (ECOS 2019). This collaboration work is multi-disciplinary as it involves research colleagues from Chemical Engineering and Molecular Systems Engineering.
Start Year 2018
 
Description Joint PhD student program with China Scholarship Council 
Organisation Tianjin University
Country China 
Sector Academic/University 
PI Contribution We accommodated a visiting PhD student from China for a year to assist our work on heat-power generation
Collaborator Contribution One visiting PhD student from the collaborating institution came in 2018. The student has helped with setting up an test-rig for organic Rankine cycles and performed modellings on the relevant power cycles.
Impact 3 x conference papers submitted: (1) 31st International Conference on Efficiency, Cost, Optimisation, Simulation and Environmental Impact of Energy Systems (ECOS 2019); (2) 5th Sustainable Thermal Energy Management International Conference (SusTEM 2019); (3) 5th International Seminar on ORC Power Systems (ORC 2019). 1 x journal paper in preparation (aimed submission Mar. 2019).
Start Year 2018
 
Description Tests and modelling of the reciprocating piston Dearman engine 
Organisation Dearman
Country United Kingdom 
Sector Private 
PI Contribution My team has developed an experimental facility, testing protocols and various models of gas spring and compressor/expander machines. Dearman's technology is exactly this type of engine and is a novel development that could benefit from the insight and tools we have developed over the course of the Pumped Thermal Electricity Storage (PTES) project.
Collaborator Contribution The relationship is in its early days, but we are currently discussing exchange of data and a joint project to support Dearman in the further development of their next-generation machines. There has also been discussion of access to a Dearman engine for testing and further development of hardware and software tools. This may involved direct funding and certainly some in-kind support but the details are not yet finalised.
Impact On-going.
Start Year 2017
 
Title Software - Real time optimisation and control of CHP energy system 
Description Given a CHP energy system, the software acquires data. The software then performs a real-time optimisation to understand the optimum values of the actuators (e.g. CHP part load) so that the system can best utilise its resources including the waste heat streams. 
Type Of Technology Software 
Year Produced 2018 
Open Source License? Yes  
Impact The software is being applied to improve the efficiency of a supermarket. And has the potential to be applied in many more, decrease the energy (and heat) waste of CHP engine. 
 
Description Centrica: CHP manufacturer - data and technology sharing for feasibility analysis purposes - 2017 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact Centrica: CHP manufacturer - data and technology sharing for feasibility analysis purposes - 2017
Year(s) Of Engagement Activity 2017
 
Description Doosan: CHP manufacturer - data and technology sharing for feasibility analysis purposes - 2018 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact Doosan: CHP manufacturer - data and technology sharing for feasibility analysis purposes - 2018
Year(s) Of Engagement Activity 2018
 
Description Enogia: ORC manufacturer - data and technology sharing for feasibility analysis purposes - 2017 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact Enogia: ORC manufacturer - data and technology sharing for feasibility analysis purposes - 2017
Year(s) Of Engagement Activity 2017
 
Description GMK: ORC manufacturer - data and technology sharing for feasibility analysis purposes - 2017 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact GMK: ORC manufacturer - data and technology sharing for feasibility analysis purposes - 2017
Year(s) Of Engagement Activity 2017
 
Description Industrial partership - AGCCE 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact Participation in project update meetings and mutliple calls.
Year(s) Of Engagement Activity 2016,2017,2018,2019
 
Description Industrial partership - ALFA LAVAL 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact A few meetings and calls about advanced heat exchangers
Year(s) Of Engagement Activity 2017,2018,2019
 
Description Industrial partership - BASEPOWER 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Industry/Business
Results and Impact A few meetings and calls.
Year(s) Of Engagement Activity 2017,2018,2019
 
Description Industrial partership - DEARMAN 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Industry/Business
Results and Impact Multiple interactions. Consultancy work and joint project application.
Year(s) Of Engagement Activity 2017,2018,2019
 
Description Industrial partership - IAV 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact A few meeting and calls. Discussion ongoing about prototype testing
Year(s) Of Engagement Activity 2017,2018,2019
 
Description Industrial partership - LIBERTINE 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact Experimental support in testing prototype.
Year(s) Of Engagement Activity 2017,2018,2019
 
Description Industrial partership - NSG 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact A few meetings and calls.
Year(s) Of Engagement Activity 2017,2018,2019
 
Description Industrial partership - PRAXAIR 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact A few visits and calls.
Year(s) Of Engagement Activity 2017,2018,2019
 
Description Industrial partership - PSE ENTERPRISE 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact Supporting in code development in gProms
Year(s) Of Engagement Activity 2017,2018,2019
 
Description Industrial partership - SOLAR POLAR 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Industry/Business
Results and Impact Support in prototype development.
Year(s) Of Engagement Activity 2017,2018,2019
 
Description Industrial partership - ST GOBAIN 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact Multiple visits and calls.
Year(s) Of Engagement Activity 2016,2017,2018,2019
 
Description Invited to attend UK-China Cold Chain Workshop 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Invited to attend UK-China Cold Chain Workshop, held in Gansu, China, 6-8 March
Year(s) Of Engagement Activity 2019
 
Description National Representative Participant in Royal Society/Chinese Academy of Sciences Policy Dialogue on Energy Storage, Dalian 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact National Representative Participant in Royal Society/Chinese Academy of Sciences Policy Dialogue on Energy Storage, Dalian, 16-17 Jan, 2019
Year(s) Of Engagement Activity 2019
 
Description Rank: ORC manufacturer - data and technology sharing for feasibility analysis purposes - 2017 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact Rank: ORC manufacturer - data and technology sharing for feasibility analysis purposes - 2017
Year(s) Of Engagement Activity 2017
 
Description Zudek: Absorption chiller manufacturer - data and technology sharing for feasibility analysis purposes - 2018 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact Zudek: Absorption chiller manufacturer - data and technology sharing for feasibility analysis purposes - 2018
Year(s) Of Engagement Activity 2018