Pumped Thermal Electricity Storage
Lead Research Organisation:
Imperial College London
Department Name: Department of Chemical Engineering
Abstract
The increasing use of renewable energy technologies for electricity generation, many of which have an unpredictably intermittent nature, will inevitably lead to a greater need for grid-scale electrical energy storage schemes. The UK government's target (as part of the EU Renewable Energy Directive) is for 20% of energy to come from renewable sources by 2020. This will require a much a higher proportion of electricity to be generated from uncontrollable sources such as wind, and one of the associated challenges will be providing sufficient electricity storage capacity to deal with the resulting variability in supply. Currently there is about 30 GWh of electricity storage capacity in the UK, with a maximum power output of around 3 GW. Nearly all of this is in the form of Pumped Hydro Storage (PHS), which is expensive and its scope for extension is limited by geographical constraints. Estimates vary, but the expert view is that our storage inventory will need to at least double over the next decade or so in order to efficiently accommodate the expanding fraction of wind and other renewable generation technologies. There is thus strong motivation to develop new, efficient and cost-effective electricity storage methods.
This project is aimed at investigating a novel storage technology known as Pumped Thermal Electricity Storage (PTES). PTES uses a high temperature-ratio heat pump to convert electrical energy into thermal energy which is then stored in two large reservoirs - one hot and one cold. The reservoirs contain gravel, or a similar high heat capacity material, and are able to store the energy much more compactly than PHS. When required, the thermal energy can be converted back into electrical energy by effectively running the heat pump backwards as a heat engine. The projected round-trip efficiency is approximately 75%, which is a little lower than PHS, but PTES has a number of potential benefits, including low capital cost and no geographical constraints. Compared to chemical energy storage methods (batteries and flow batteries) it also has the advantage of not requiring any hazardous or scarce substances.
The success of PTES will hinge upon minimising the effect of various thermodynamic irreversibilities (for example, heat transfer across substantial temperature differences and losses associated with compression and expansion of the working fluid) whilst simultaneously keeping capital costs low. Accordingly, the proposed work focuses on investigating fundamental thermodynamic, fluid flow and heat transfer processes using a combination of experimental, theoretical and computational methods. An important aim of the work is also to develop and validate an overall system model and to use this to optimise the design and operation strategy, and to examine the benefits that PTES might bring to the electricity supply chain.
This project is aimed at investigating a novel storage technology known as Pumped Thermal Electricity Storage (PTES). PTES uses a high temperature-ratio heat pump to convert electrical energy into thermal energy which is then stored in two large reservoirs - one hot and one cold. The reservoirs contain gravel, or a similar high heat capacity material, and are able to store the energy much more compactly than PHS. When required, the thermal energy can be converted back into electrical energy by effectively running the heat pump backwards as a heat engine. The projected round-trip efficiency is approximately 75%, which is a little lower than PHS, but PTES has a number of potential benefits, including low capital cost and no geographical constraints. Compared to chemical energy storage methods (batteries and flow batteries) it also has the advantage of not requiring any hazardous or scarce substances.
The success of PTES will hinge upon minimising the effect of various thermodynamic irreversibilities (for example, heat transfer across substantial temperature differences and losses associated with compression and expansion of the working fluid) whilst simultaneously keeping capital costs low. Accordingly, the proposed work focuses on investigating fundamental thermodynamic, fluid flow and heat transfer processes using a combination of experimental, theoretical and computational methods. An important aim of the work is also to develop and validate an overall system model and to use this to optimise the design and operation strategy, and to examine the benefits that PTES might bring to the electricity supply chain.
Organisations
- Imperial College London, United Kingdom (Lead Research Organisation)
- Nanyang Technological University, Singapore (Collaboration)
- US Dept of Energy, United States (Collaboration)
- University of Birmingham, United Kingdom (Collaboration)
- Technical University of Denmark (Collaboration)
- University of Bari Aldo Moro (Collaboration)
- Chinese Academy of Sciences (Collaboration)
- Dearman (Collaboration)
- University of Cambridge (Collaboration)
- University of Aberdeen, United Kingdom (Collaboration)
- German Aerospace Centre (DLR) (Collaboration)
- Shanghai Jiao Tong University, China (Collaboration)
- Xian Jiaotong University, China (Collaboration)
Publications
Charogiannis A
(2017)
Statistical characteristics of falling-film flows: A synergistic approach at the crossroads of direct numerical simulations and experiments
in Physical Review Fluids
Charogiannis A
(2017)
Detailed hydrodynamic characterization of harmonically excited falling-film flows: A combined experimental and computational study
in Physical Review Fluids
Dirker J
(2019)
Thermal Energy Processes in Direct Steam Generation Solar Systems: Boiling, Condensation and Energy Storage - A Review
in Frontiers in Energy Research
Freeman J
(2015)
An assessment of solar-powered organic Rankine cycle systems for combined heating and power in UK domestic applications
in Applied Energy
Georgiou S
(2020)
On the value of liquid-air and pumped-thermal electricity storage systems in low-carbon electricity systems
in Energy
Georgiou S
(2018)
A thermo-economic analysis and comparison of pumped-thermal and liquid-air electricity storage systems
in Applied Energy
| Description | This project has led to the construction of an experimental facility and measurement tools, as well as to the development of a range of models (from fully resolved CFD models to more simplified lumped but dynamic models) that can be used to understand loss mechanisms in reciprocating thermodynamic systems, and for the proposal of next-generation high-performance systems. The loss mechanisms in such components were studied in detail with a combination of the above mentioned experimental and numerical methods and insight has been gained on how and which mechanisms we can minimised in our attempt to design high-performance components for applications in energy storage, but also beyond this, e.g., distributed power generation systems and even cooling systems. |
| Exploitation Route | The models developed in this project have taken the form of design tools and software package libraries that are now being used to propose new or improved machines with high-efficiency (e.g. we are currently in discussions with Dearman on how to collaborate in support of their reciprocating engine technology). On the experimental front, the measurement facility has provide information for model validation, but is also under current modification for use as a testing facility for novel piston-expanders in the EPSRC project "Energy-Use Minimisation via High Performance Heat-Power-Cooling Conversion and Integration: A Holistic Molecules to Technologies to Systems Approach" (EP/P004709/1), and also a project funded by Climate-KIC on expanders used in a technology aimed as improving the performance and efficiency of refrigeration systems by company Thermaflex. This information and data will be made available via open access publications. |
| Sectors | Agriculture, Food and Drink,Chemicals,Construction,Creative Economy,Energy,Manufacturing, including Industrial Biotechology,Transport |
| Description | The findings have been communicated to a number of companies and academic partners, and we are working to define various cooperative technology development and testing activities in various projects currently running (or being discussed) at Imperial College London. Specifically, a high-performance reciprocating expander, for example, is a key component of a technology aimed at being retrofitted to refrigeration systems for improved performance and efficiency, that is being developed by UK SME Thermaflex. Thermaflex has obtained funding and their technology has been tested in our facilities, which has shown great potential for energy savings and decarbonisation of cooling. A high-performance expander is also a key component of a number of distributed power-generation systems such as ORC systems and other applications for solar power generation or waste-heat recovery and conversion, and innovative combined cooling-power technologies such as the Dearman engine. We are working closely with a range of energy systems/technology companies to guide the further development of their technologies, as well as reciprocating-piston expander/component companies (Libertine FPE/UK, IVA/Germany) and heat pump manufacturers, with, to date, multiple collaborations, secondments and project funding from Mitsubishi Electric R&D Centre Europe (MERCE-UK). In addition, we have an interest in the further development of our own reciprocating-piston energy technology. These activities are part of other funded projects by EPSRC (e.g., "Energy-Use Minimisation via High Performance Heat-Power-Cooling Conversion and Integration: A Holistic Molecules to Technologies to Systems Approach"/EP/P004709/1; "High Temperature, High Efficiency PV-Thermal Solar System"/EP/M025012/1). We have also developed new collaborations thanks to our in-depth understanding of the unsteady conjugate gas-to-wall heat transfer gained during this project. In particular, we are closely working with a French research team from Arts et Métiers ParisTech on the development of forced convective cooling in liquid-piston engines to achieve near-isothermal compression for compact and efficient delivery of ultra-high pressure hydrogen, which is key to the successful uptake of long-range hydrogen-powered vehicles. A paper has recently been submitted to Applied Thermal Engineering and we are currently working on an additional one. Finally, we have provided guidance to make better selection and design of components when building pumped-thermal electricity storage systems. For example, the magazine article in the Professional Engineering magazine of IMechE reaches a large and wide range of non-academic stakeholders. Furthermore, the review paper on thermo-mechanical energy storage is open-access and has been downloaded by ~5000 people both from an academic and a non-academic background. |
| First Year Of Impact | 2014 |
| Sector | Chemicals,Construction,Creative Economy,Energy,Manufacturing, including Industrial Biotechology,Transport |
| Impact Types | Societal,Economic |
| Description | Article in the Professional Engineering Magazine of the Institution of Mechanical Engineers |
| Geographic Reach | Multiple continents/international |
| Policy Influence Type | Contribution to new or Improved professional practice |
| Description | Contribution to the white paper on 'Liquid Air in the Energy and Transport Systems' |
| Geographic Reach | Asia |
| Policy Influence Type | Citation in other policy documents |
| Impact | The white paper (Liquid Air Energy White Paper) was widely disseminated and also presented at the "Liquid Air Energy Conference" that took place at the Royal Academy of Engineering on 9th May 2013, which was attended by ~150 people. Liquid air energy storage is now considered one of the most promising solutions for large-scale storage, promising to service a growing multi billion dollar energy storage market (estimated global potential for grid energy storage by 2017 is $113.5 billion, accounting for 185GWh (52GW) of capacity). |
| Description | Discussion of advancements in solar-powered systems based on reciprocating systems for small-scale applications at DECC |
| Geographic Reach | Asia |
| Policy Influence Type | Contribution to a national consultation/review |
| Impact | Solar-PV is generally acknowledged as an excellent solution for the delivery clean, sustainable power to households. However, PV technology is expensive, as is electricity storage, and also has very significant levels of embedded energy. The present discussion with personnel from DECC centred around alternative thermal-based solutions (e.g. ORC power-generations systems, based on suitable reciprocating components which are idea at such small-scales), far more affordable thermal energy storage, and dual energy output (electrical and thermal, e.g. for hot water) leading to much lower costs per unit energy. DECC expressed a very real interest in this alternative, also thanks to the far more flexible, controllable and wide operating envelope of such a system. Given this encouragements, we are currently investigating this technology further and as soon as we have more concrete proof of the system's performance will return to DECC in order to progress the discussion into future directions of investment/policy. |
| Description | Lead the cross-faculty Energy Futures Lab Energy Efficiency Research Network at Imperial College |
| Geographic Reach | Asia |
| Policy Influence Type | Membership of a guideline committee |
| Impact | xxx |
| Description | Accelerator voucher |
| Amount | £39,998 (GBP) |
| Organisation | Climate-KIC |
| Sector | Charity/Non Profit |
| Country | United Kingdom |
| Start | 09/2016 |
| End | 12/2016 |
| Description | Africa Capacity Building Initiative |
| Amount | £1,017,430 (GBP) |
| Funding ID | AQ150077 |
| Organisation | The Royal Society |
| Sector | Charity/Non Profit |
| Country | United Kingdom |
| Start | 01/2016 |
| End | 01/2021 |
| Description | EU FP7 SME |
| Amount | £210,000 (GBP) |
| Funding ID | FP7-SME-2013/BSG-SME/605826 |
| Organisation | European Commission |
| Sector | Public |
| Country | European Union (EU) |
| Start | 08/2013 |
| End | 08/2015 |
| Description | Reducing Industrial Energy Demand (REDIMS) |
| Amount | £1,573,522 (GBP) |
| Funding ID | EP/P004709/1 |
| Organisation | Engineering and Physical Sciences Research Council (EPSRC) |
| Sector | Public |
| Country | United Kingdom |
| Start | 12/2016 |
| End | 12/2020 |
| Description | Supergen Solar Challenge |
| Amount | £1,108,936 (GBP) |
| Funding ID | EP/M025012/1 |
| Organisation | Engineering and Physical Sciences Research Council (EPSRC) |
| Sector | Public |
| Country | United Kingdom |
| Start | 07/2015 |
| End | 07/2018 |
| Title | Experimental facility for the testing of reciprocating machines (compressors, expanders and gas springs) |
| Description | An experiment is devised to measure the thermodynamic loss associated with the unsteady heat transfer that takes place in the compression space of a gas spring and differentiate the loss from any mass leakage or viscous or dissipation frictional effects. As the total mass in the system is unknown, due to leakage between the cylinder and the piston, it is necessary to measure three thermodynamic bulk parameters in order to completely determine the system state. Pressure, temperature and volume are convenient choices. However there is a challenge in measuring the gas temperature in the compression space using traditional physically invasive methods, such as thermocouples. These methods generally have a number of undesirable side effects; for example their poor response times due to the added thermal mass, their sensitivity to the varying heat transfer in the cylinder, the disruption of the gas flow and gas temperature, and the fact that they only provide a point measurement of the flow. In this facility a novel technique is developed for the measuring of the temperature of the gas by measuring the time of flight of an ultrasonic pulse across the compression space. The technique is based on the principal that the speed of sound in an ideal gas is dependent on the square root of the absolute temperature, based on which the temperature of the gas along the ultrasonic path can be found. The ultrasonic pulse is transmitted and received at 400 kHz using piezo ceramic transducers with a repetition rate of 2 kHz. This work is being conducted to characterise the heat transfer and resulting thermodynamic loss in all reciprocating machines, and the knowledge gained will not just be limited to gas springs but also be able to be applied to compressors expanders. |
| Type Of Material | Improvements to research infrastructure |
| Year Produced | 2013 |
| Provided To Others? | Yes |
| Impact | Reducing unsteady thermal losses in the Pumped Thermal Energy Storage (PTES) system. Quantifying the performance of such systems. Demonstrating the capability of reciprocating compression/expansion systems for PTES, but also alternative power-generation systems/technologies. Generation of data for model validation of such components. The capability the formed the basis of funding applications (e.g. EU H2020, and EPSRC). |
| URL | http://www.isentropic.co.uk/our-phes-technology |
| Title | Signal delay method based on cross-correlation of the received and transmitted signals in the frequency domain |
| Description | Method for finding the signal delay between the received and transmitted signal cross-correlation of the signals in the frequency domain with digital processing and filtering for ultrasonic device data processing. Used for temperature measurement based on the time of flight across a cavity. The digital filtering consists of a notch filter in the frequency domain and a frequency down shift. Conversion back to the time domain with an fft and taking the absolute value of the complex signal, the location of the resulting peak gives the delay time. |
| Type Of Material | Improvements to research infrastructure |
| Provided To Others? | No |
| Impact | Very high resolution and fidelity (2 kHz) measurements of transient gas temperatures. Development of new instrument with a capability of simultaneous gas density and temperature. This capability has formed the basis of discussions with companies (e.g. ABB, Shell, Isentropic, Dearman) as well as a capability the formed the basis of funding applications (e.g. EU H2020, Climate-KIC). |
| Title | Cascaded latent heat store models and packed-bed sensible/latent heat store models for pumped-thermal energy storage |
| Description | These models are developed using PDE's integration and a numerical solver. The models include a conjugate description of heat transfer and thermos-economic optimization can be performed using these models. |
| Type Of Material | Computer model/algorithm |
| Year Produced | 2020 |
| Provided To Others? | Yes |
| Impact | These models are developed using PDE's integration and a numerical solver. The models include a conjugate description of heat transfer and thermos-economic optimization can be performed using these models. |
| Title | Compressed Air Energy Storage: Lumped parameter model to capture most of the phenomena in the compression phase of the CAES process |
| Description | The model captures the heat transfer interaction between the compressed gas (air) and the compressing agent (water) to approximate an isothermal process. Interaction with the walls and surrounds is also taken into account. Heat transfer is enhanced by the use of conventional techniques in a novel way not yet explicitly appearing in the published literature. |
| Type Of Material | Computer model/algorithm |
| Year Produced | 2020 |
| Provided To Others? | No |
| Impact | This modelling was originally proposed as part of an industrial offering by a wind farm manufacturer where the patent was originally initiated (now transferred). The potential is being exploited with a number of possible funders for the use in sustainable refrigeration for vulnerable crops in Kenya - the modelling and experimentation will demonstrate the feasibility of the proposed compression/cycle system. |
| Title | Development of thermodynamic and component-costing models of various electricity storage technologies. |
| Description | Computer models of the thermo-economic performance of different storage options at different discharge power ratings and discharge durations were developed. |
| Type Of Material | Computer model/algorithm |
| Year Produced | 2021 |
| Provided To Others? | Yes |
| Impact | The review paper has been published and aims to provide evidence for the future evolution of large-scale electricity storage systems. |
| Title | Gathering of literature based on pumped-thermal electricity storage |
| Description | A comprehensive review of all literature based on pumped-thermal electricity storage was conducted, and a book chapter was prepared discussing the possible configurations and the up-to-date progress of these systems. |
| Type Of Material | Computer model/algorithm |
| Year Produced | 2022 |
| Provided To Others? | Yes |
| Impact | A book chapter is available online and several papers are in preparation. |
| Title | Lumped (reduced-order) models for prediction of performance and cost of components (compressors, expanders, heat exchangers etc.) that make up storage technologies |
| Description | Thermo-economic for prediction of performance and cost of thermo-mechanical storage technologies at different scales are developed by the various groups involved in the project. |
| Type Of Material | Computer model/algorithm |
| Year Produced | 2020 |
| Provided To Others? | No |
| Impact | Sevaral papers based on the model are in preparation. |
| Title | Lumped models estimating the performance and cost of compressors, expanders, heat exchangers and other components that make up storage technologies have been produced. |
| Description | We have used a unified framework where all considered thermo-mechanical electricity storage options have been modelled using a consistent set of assumptions. |
| Type Of Material | Computer model/algorithm |
| Year Produced | 2021 |
| Provided To Others? | Yes |
| Impact | This is the first time a detailed techno-economic analysis of the main thermo-mechanical energy storage options has been performed for a large range of sizes under a unified modelling framework This gives added value and confidence to the comparisons we have made and to the conclusions drawn from those comparisons. |
| Title | Novel data analysis methods or techniques: Proposal of a new framework for understanding and quantifying rigorously the different loss mechanisms in reciprocating machines (compressors, expanders and gas springs) |
| Description | The framework allows the rigorous breakdown of losses into thermal/heat transfer-based and pressure/fluid mechanical-based. This is done both during a cycle of operation of a reciprocating (or similar) device, and an average over the cycle. |
| Type Of Material | Computer model/algorithm |
| Year Produced | 2014 |
| Provided To Others? | Yes |
| Impact | We are currently interacting with a group in Denmark led by Professor Fredrik Haglind to translate this model to programmes written in the Modelica language, which is being developed for relevant systems. |
| Title | Pumped thermal electricity storage lumped-capacity model |
| Description | This dynamic reduced-order model predicts the thermodynamic part-load performance of a reversible Joule/Brayton cycle used as an electricity storage technology, reversible Joule-Brayton cycle engine, where energy is stored as sensible heat in hot and cold thermal stores, while the temperature difference is achieved through gas compression and expansion processes. |
| Type Of Material | Computer model/algorithm |
| Year Produced | 2020 |
| Provided To Others? | Yes |
| Impact | Conference paper and upcoming journal publications. |
| Title | Simplified, lumped (reduced-order) models for prediction of thermal losses; application to performance of reciprocating machines (compressors, expanders and gas springs) |
| Description | A lumped model of the cavity in a reciprocating machine was developed using PDE's intergration and an numerical solver. The model includes a conjugate description of heat transfer, thus accounting for the role of solid walls in relevant processes. |
| Type Of Material | Computer model/algorithm |
| Year Produced | 2012 |
| Provided To Others? | Yes |
| Impact | This model won the HEFAT2012 best paper prize, and led to an article publication in an international journal (Heat Transfer Engineering). The conjugate heat transfer aspects of this model were applied to data provide by and in collaboration with Professor Hajime Nakamura at the Japanese Defence Academy, and additional funding in the form of a £0.84M, 3-year EPSRC project [EP/K008595]. We are also currently interacting with a group in Denmark led by Professor Fredrik Haglind to translate this model to programmes written in the Modelica language, which is being developed for relevant systems. |
| Title | Thermo-economic models for energy storage technologies |
| Description | Lumped-mass thermo-economic models estimating the performance and cost of compressors, expanders, heat exchangers and other components that make up storage technologies have been extended. We have used a unified framework where all considered thermo-mechanical electricity storage options have been modelled using a consistent set of assumptions. Possible components now involve various types of compressors and heat exchangers. |
| Type Of Material | Computer model/algorithm |
| Year Produced | 2021 |
| Provided To Others? | Yes |
| Impact | All thermoeconomic models of energy storage technologies are based on similar assumptions and modelling methodology, which means a like-to-like comparison is possible. |
| Title | Thermodynamic and component-costing models of pumped-thermal electricity storage |
| Description | Computer models of the thermo-economic performance of different configurations of pumped thermal electricity storage have been developed. Insights were provided about the role of thermal storage when employing sensible heat storage materials. |
| Type Of Material | Computer model/algorithm |
| Year Produced | 2022 |
| Provided To Others? | Yes |
| Impact | Two papers based on pumped thermal electricity storage are published aiming to provide evidence for the future evolution of large-scale electricity storage systems and several other papers are in preparation. |
| Title | Thermodynamic models and cost correlations from manufacturers/literature |
| Description | Detailed thermo-economic comparison between the considered storage options requires the use of modelling tools (e.g. Matlab) to develop models which are validated against data or experiments. |
| Type Of Material | Database/Collection of data |
| Year Produced | 2020 |
| Provided To Others? | No |
| Impact | Several papers based on the models and database are in preparation. |
| 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 | Experiments on our reciprocating expander facility - P. Farres-Antunez |
| Organisation | University of Cambridge |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | We have provided access to our reciprocating expander facility as well as guidance and knowledge during the visit of Mr. Pau Farres-Antunez. |
| Collaborator Contribution | Mr. Farres-Antunez helped with the design, development and commissioning of acoustic shielding/isolation for the ultrasonic probe used for temperature measurements. |
| Impact | A new ultrasonic probe capable of simultaneous high-frequency temperature and density measurements in a gas space, in our case, applied and tested in an reciprocating expander for operational characterisation. Following his stay with us, Mr. Farres-Antunez moved to Cambridge to start a PhD under the supervision of Pumped Thermal Electricity Storage (PTES) project partner Dr. Alexander White on the modelling of new variants of the PTES system. Our interaction has continued in this new capacity. |
| Start Year | 2012 |
| Description | Experiments/modelling of reciprocating expander - J. Wronski |
| Organisation | Technical University of Denmark |
| Country | Denmark |
| Sector | Academic/University |
| PI Contribution | Simple (reduced-order) modelling codes and experimental data from our reciprocating expander facility. During the collaboration, we compared these results with an Opensource Modelica based reciprocating expander/compressor model (developed by Mr Wronski). In particular, the Imperial contributed towards the improved heat transfer description of the process being investigated. |
| Collaborator Contribution | Opensource Modelica based reciprocating expander/compressor model (developed by Mr Wronski) for systems design of refrigorators, ORC's and other applications. Mr Wronski supplied his codes and models of the same system. |
| Impact | New experimental data was generated and made available for the refinement of modelling codes for the prediction of the performance of reciprocating components. In parallel, revised modules/functions were developed for these codes. |
| Start Year | 2012 |
| Description | International Postdoctoral Exchange Fellowship Program with the Office of China Postdoc Council |
| Organisation | Shanghai Jiao Tong University |
| Country | China |
| Sector | Academic/University |
| PI Contribution | We accommodated a visiting postdoctoral researcher from China for 2 years to assist our work on thermal energy storage. |
| Collaborator Contribution | A visiting postdoctoral researcher from the collaborating institution came in 2019. The postdoc has helped with setting up a test-rig for thermal energy storage and performed modelling on the relevant projects. |
| Impact | Several papers in preparation. |
| Start Year | 2019 |
| Description | Joint PhD student program with China Scholarship Council |
| Organisation | Xi'an Jiaotong University |
| Country | China |
| Sector | Academic/University |
| PI Contribution | We accommodated a visiting PhD student from China for a year to assist our work on pumped thermal electricity storage. |
| Collaborator Contribution | One visiting PhD student from the collaborating institution came in 2019. The student has helped with setting up a performed modelling on the relevant pumped thermal electricity storage technology. |
| Impact | Several papers are in preparation. |
| Start Year | 2019 |
| Description | Review and comparison of thermo-mechanical energy storage systems |
| Organisation | Chinese Academy of Sciences |
| Country | China |
| Sector | Public |
| PI Contribution | We have published a review of a class of promising bulk energy storage technologies based on thermo-mechanical principles, which includes: compressed-air energy storage (CAES), liquid-air energy storage (LAES) and pumped-thermal electricity storage (PTES). The thermodynamic principles upon which these thermo-mechanical energy storage (TMES) technologies are based were discussed and a synopsis of recent progress in their development was presented. |
| Collaborator Contribution | They provided thermodynamic and component-costing models to capture the technical and economic characteristics of different storage options. |
| Impact | Olympios AV, McTigue JD, Farres-Antunez P, Tafone A, Romagnoli A, Li Y, Ding Y, Steinmann WD, Thess A, Wang L, Chen, H, Markides CN. Progress and prospects of thermo-mechanical energy storage - A critical review. Progress in Energy 2021. |
| Start Year | 2019 |
| Description | Review and comparison of thermo-mechanical energy storage systems |
| Organisation | German Aerospace Centre (DLR) |
| Country | Germany |
| Sector | Public |
| PI Contribution | We have published a review of a class of promising bulk energy storage technologies based on thermo-mechanical principles, which includes: compressed-air energy storage (CAES), liquid-air energy storage (LAES) and pumped-thermal electricity storage (PTES). The thermodynamic principles upon which these thermo-mechanical energy storage (TMES) technologies are based were discussed and a synopsis of recent progress in their development was presented. |
| Collaborator Contribution | They provided thermodynamic and component-costing models to capture the technical and economic characteristics of different storage options. |
| Impact | Olympios AV, McTigue JD, Farres-Antunez P, Tafone A, Romagnoli A, Li Y, Ding Y, Steinmann WD, Thess A, Wang L, Chen, H, Markides CN. Progress and prospects of thermo-mechanical energy storage - A critical review. Progress in Energy 2021. |
| Start Year | 2019 |
| Description | Review and comparison of thermo-mechanical energy storage systems |
| Organisation | Nanyang Technological University |
| Department | School of Physics and Mathematical Sciences |
| Country | Singapore |
| Sector | Academic/University |
| PI Contribution | We have published a review of a class of promising bulk energy storage technologies based on thermo-mechanical principles, which includes: compressed-air energy storage (CAES), liquid-air energy storage (LAES) and pumped-thermal electricity storage (PTES). The thermodynamic principles upon which these thermo-mechanical energy storage (TMES) technologies are based were discussed and a synopsis of recent progress in their development was presented. |
| Collaborator Contribution | They provided thermodynamic and component-costing models to capture the technical and economic characteristics of different storage options. |
| Impact | Olympios AV, McTigue JD, Farres-Antunez P, Tafone A, Romagnoli A, Li Y, Ding Y, Steinmann WD, Thess A, Wang L, Chen, H, Markides CN. Progress and prospects of thermo-mechanical energy storage - A critical review. Progress in Energy 2021. |
| Start Year | 2019 |
| Description | Review and comparison of thermo-mechanical energy storage systems |
| Organisation | U.S. Department of Energy |
| Department | National Renewable Energy Laboratory (NREL) |
| Country | United States |
| Sector | Public |
| PI Contribution | We have published a review of a class of promising bulk energy storage technologies based on thermo-mechanical principles, which includes: compressed-air energy storage (CAES), liquid-air energy storage (LAES) and pumped-thermal electricity storage (PTES). The thermodynamic principles upon which these thermo-mechanical energy storage (TMES) technologies are based were discussed and a synopsis of recent progress in their development was presented. |
| Collaborator Contribution | They provided thermodynamic and component-costing models to capture the technical and economic characteristics of different storage options. |
| Impact | Olympios AV, McTigue JD, Farres-Antunez P, Tafone A, Romagnoli A, Li Y, Ding Y, Steinmann WD, Thess A, Wang L, Chen, H, Markides CN. Progress and prospects of thermo-mechanical energy storage - A critical review. Progress in Energy 2021. |
| Start Year | 2019 |
| Description | Review and comparison of thermo-mechanical energy storage systems |
| Organisation | University of Birmingham |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | We have published a review of a class of promising bulk energy storage technologies based on thermo-mechanical principles, which includes: compressed-air energy storage (CAES), liquid-air energy storage (LAES) and pumped-thermal electricity storage (PTES). The thermodynamic principles upon which these thermo-mechanical energy storage (TMES) technologies are based were discussed and a synopsis of recent progress in their development was presented. |
| Collaborator Contribution | They provided thermodynamic and component-costing models to capture the technical and economic characteristics of different storage options. |
| Impact | Olympios AV, McTigue JD, Farres-Antunez P, Tafone A, Romagnoli A, Li Y, Ding Y, Steinmann WD, Thess A, Wang L, Chen, H, Markides CN. Progress and prospects of thermo-mechanical energy storage - A critical review. Progress in Energy 2021. |
| Start Year | 2019 |
| Description | Review and comparison of thermo-mechanical energy storage systems |
| Organisation | University of Cambridge |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | We have published a review of a class of promising bulk energy storage technologies based on thermo-mechanical principles, which includes: compressed-air energy storage (CAES), liquid-air energy storage (LAES) and pumped-thermal electricity storage (PTES). The thermodynamic principles upon which these thermo-mechanical energy storage (TMES) technologies are based were discussed and a synopsis of recent progress in their development was presented. |
| Collaborator Contribution | They provided thermodynamic and component-costing models to capture the technical and economic characteristics of different storage options. |
| Impact | Olympios AV, McTigue JD, Farres-Antunez P, Tafone A, Romagnoli A, Li Y, Ding Y, Steinmann WD, Thess A, Wang L, Chen, H, Markides CN. Progress and prospects of thermo-mechanical energy storage - A critical review. Progress in Energy 2021. |
| Start Year | 2019 |
| Description | Review paper on energy storage technologies |
| Organisation | Chinese Academy of Sciences |
| Country | China |
| Sector | Public |
| PI Contribution | We use thermodynamic models to capture different configurations and design options and to therefore compare thermo-mechanical energy storage technologies within a unified modelling framework. |
| Collaborator Contribution | They provide their expertise and models to capture the technical and cost prediction complexities associated with each type of thermo-mechanical storage system. |
| Impact | We aim to write a review paper that provides a detailed and fair thermo-economic comparison of thermo-mechanical energy storage technologies, which can be used as a benchmark for the future evolution of these highly-promising solutions. |
| Start Year | 2019 |
| Description | Review paper on energy storage technologies |
| Organisation | German Aerospace Centre (DLR) |
| Country | Germany |
| Sector | Public |
| PI Contribution | We use thermodynamic models to capture different configurations and design options and to therefore compare thermo-mechanical energy storage technologies within a unified modelling framework. |
| Collaborator Contribution | They provide their expertise and models to capture the technical and cost prediction complexities associated with each type of thermo-mechanical storage system. |
| Impact | We aim to write a review paper that provides a detailed and fair thermo-economic comparison of thermo-mechanical energy storage technologies, which can be used as a benchmark for the future evolution of these highly-promising solutions. |
| Start Year | 2019 |
| Description | Review paper on energy storage technologies |
| Organisation | Nanyang Technological University |
| Country | Singapore |
| Sector | Academic/University |
| PI Contribution | We use thermodynamic models to capture different configurations and design options and to therefore compare thermo-mechanical energy storage technologies within a unified modelling framework. |
| Collaborator Contribution | They provide their expertise and models to capture the technical and cost prediction complexities associated with each type of thermo-mechanical storage system. |
| Impact | We aim to write a review paper that provides a detailed and fair thermo-economic comparison of thermo-mechanical energy storage technologies, which can be used as a benchmark for the future evolution of these highly-promising solutions. |
| Start Year | 2019 |
| Description | Review paper on energy storage technologies |
| Organisation | U.S. Department of Energy |
| Department | National Renewable Energy Laboratory (NREL) |
| Country | United States |
| Sector | Public |
| PI Contribution | We use thermodynamic models to capture different configurations and design options and to therefore compare thermo-mechanical energy storage technologies within a unified modelling framework. |
| Collaborator Contribution | They provide their expertise and models to capture the technical and cost prediction complexities associated with each type of thermo-mechanical storage system. |
| Impact | We aim to write a review paper that provides a detailed and fair thermo-economic comparison of thermo-mechanical energy storage technologies, which can be used as a benchmark for the future evolution of these highly-promising solutions. |
| Start Year | 2019 |
| Description | Review paper on energy storage technologies |
| Organisation | University of Birmingham |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | We use thermodynamic models to capture different configurations and design options and to therefore compare thermo-mechanical energy storage technologies within a unified modelling framework. |
| Collaborator Contribution | They provide their expertise and models to capture the technical and cost prediction complexities associated with each type of thermo-mechanical storage system. |
| Impact | We aim to write a review paper that provides a detailed and fair thermo-economic comparison of thermo-mechanical energy storage technologies, which can be used as a benchmark for the future evolution of these highly-promising solutions. |
| Start Year | 2019 |
| Description | Sabbatical year at Imperial College London - Professor Drazen Fabris |
| Organisation | University of Aberdeen |
| Department | School of Engineering |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | Professor Drazen Fabris and I made contact at the HEFAT 2012 conference where I had presented the paper: A FRAMEWORK FOR THE ANALYSIS OF THERMAL LOSSES IN RECIPROCATING COMPRESSORS AND EXPANDERS (by Mathie R., Markides C.N.* and White A.J.) This initial contact formed the start of an on-going discussion on the experimental testing and modelling of reciprocating machines, mainly in the context of the Pumped Thermal Electricity Storage (PTES) system in this project, but also beyond. This on-going discussion led to my inviting him to spend a year in London visiting and working with me and also a number of relevant people in my group as part of his sabbatical. During his time in London, we made available the gas-spring apparatus that we had constructed in our laboratories as part of the PTES project, CFD and lumped modelling tools, and a number of Postdoctoral researchers, PhD and Masters students who interacted closely with him during his time in London. He is now back in Santa Clara, but the collaboration is continuing on experimental and modelling aspects of high-performance components for use in different energy applications. |
| Collaborator Contribution | Professor Fabris worked closely with Dr. Paul Sapin (assigned to the PTES project) in identifying a suitable correlation method that is now currently used for the in-line ultrasonic temperature measurements in our gas spring apparatus. He also supported the experimental work but assisting with error analysis and propagation in the measurements of pressure, volume and temperature. Professor Fabris also worked to assist Dr. Sapin along with PhD student Mr. Aly Taleb in performing a series of CFD simulations of gas springs in OpenFOAM, both with ideal gases and also investigating the role of real gas effects. Finally, Professor Fabris, Dr. Sapin and I also worked to develop a pseudo-2D code to predict the thermal processes reciprocating-piston spaces. |
| Impact | We have developed new tools for the experimental measurements in reciprocating gas springs (the most involved of which is the in-line ultrasonic temperature technique) that allow the full lumped, dynamic investigation of these systems and the evaluation of cycle-resolved mass leakage and heat transfer. We have also developed a pseudo-2D code to predict the thermal processes in reciprocating-piston spaces, and performed CFD simulations of gas springs in OpenFOAM, both with ideal gases and also investigating the role of real gas effects. The motivation behind these various strands of research has been to validate the detailed simulations against the experimental data, and then to use the full knowledge of the flow and thermal fields in the former to develop more simple lumped, dynamic models of the gas dsirng processes. These final models can then act as reliable design tools for reciprocating machines, such as compressors and expanders. |
| Start Year | 2014 |
| 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 | Reduced order model (ROM) codes for gas spring, compressor and expander simulations |
| Description | These software codes allow a user to perform fast calculations of the thermal and pressure losses (where relevant) in gas springs and compressors/expanders for the purpose of early-stage design/operation, and appreciation of the relative magnitude of losses. |
| Type Of Technology | Software |
| Year Produced | 2016 |
| Impact | The codes are being used to provide thermal and pressure (where relevant) loss variations with important design (e.g. geometry of the compression/expansion space) and operation (frequency, valve timings). These have formed the basis of a closer interaction with the Universities of Ghent and Liege, and also with companies like Dearman and IAV. Ultimately, an attempt will be made to incorporate these into libraries for the modelling of reciprocating machines, but also for suggesting next-generation high-performance compression/expansion machines. |
| Title | Software - Pseudo/Two-dimensional, time-resolved dynamic codes in Matlab for gas spring simulations |
| Description | Pseudo/Two-dimensional, time-resolved dynamic codes in Matlab for solving the heat transfer problem in a cylindrical geometry without the need for imposed (empirical) heat transfer coefficients. |
| Type Of Technology | Software |
| Year Produced | 2017 |
| Impact | On-going |
| Title | Three-dimensional, time-resolved CFD codes in OpenFOAM for gas spring simulations |
| Description | OpenFOAM is a free, open source CFD software package. Cases were set-up using the OpenFOAM coldengine foam solver. The cases included techniques for novel boundary conditions, dynamic meshing, and analysis. |
| Type Of Technology | Software |
| Year Produced | 2017 |
| Open Source License? | Yes |
| Impact | The code is now being used to provide detailed on flow and heat transfer in compression/expansion spaces in the presence of net flow through these spaces and (importantly) behind meshes/orifices which more realistically represent the flow that would be expected in high-performance such systems. These data will have also formed a point of contact with other groups (e.g. Denmark Technical University, University of Twente, University of Ghent) who require this for advanced model and practical system development, as well as non-academic/industrial contacts (e.g. Isentropic Ltd., Dearman Ltd.) |
| Title | Ultrasonic device for simultaneous density and average temperature measurements |
| Description | New ultrasonic device for simultaneous density and average temperature measurements in reciprocating machines (compressors, expanders and gas springs) based on time-of-flight of high-frequency carrier. |
| Type Of Technology | New/Improved Technique/Technology |
| Year Produced | 2016 |
| Impact | The capability enabled by this device has formed the basis of discussions with companies (e.g. ABB, Shell, Isentropic, Dearman) and formed the basis of funding applications (e.g. EU H2020, Climate-KIC). |
| Description | AIChE Conference Session Keynote Speech (San Francisco) |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | Invited keynote presentation in a session of the annual American Institute of Chemical Engineers (AIChE) on next-generation high-efficiency conversion systems with integrated storage, followed by questions from the audience and discussion. |
| Year(s) Of Engagement Activity | 2016 |
| Description | Chair 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics |
| Form Of Engagement Activity | A formal working group, expert panel or dialogue |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Participants in your research and patient groups |
| Results and Impact | Facilitated the event; chairing led to discussion with presenters and members of the audience. Discussion led to: (1) suggestions for a number visit/exchanges; and (2) suggestions for an extension to some work that found its way into a related publication, namely: R. Mathie, C.N. Markides*, A. White, A Framework for the Analysis of Thermal Losses in Reciprocating Compressors and Expanders. Heat Transfer Engineering, 35 (2014) 1435-1449. |
| Year(s) Of Engagement Activity | 2012 |
| Description | Contribution to RCUK SUPERGEN Energy Storage Scoping Workshop |
| Form Of Engagement Activity | A formal working group, expert panel or dialogue |
| Part Of Official Scheme? | Yes |
| Geographic Reach | National |
| Primary Audience | Participants in your research and patient groups |
| Results and Impact | We had discussions covering all aspects of energy storage in the UK, to guide research directions in recent years. My contribution was to highlight the importance in thermal energy storage, as well as large-scale energy storage with systems such as PTES (under development in this EPSRC project) and similar ones. The areas that were suggested (i.e. thermal energy storage, as well as large-scale energy storage with systems such as PTES and similar thermodynamic systems) were acknowledged as important parts of any future energy storage technology portfolio for the UK. |
| Year(s) Of Engagement Activity | 2013 |
| Description | Meeting industrial partners and engaging in STEMnet activities (Women in Engineering Day) |
| 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 | My colleague (and industrial contact) holds the patent for the overall project - our updates were to inform him of progress and to field queries which arose as a result of his funding bids. As a result, considerable interest in the project was generated. The STEM activity - held at the Institution of Mechanical Engineers was part of an activity with several organisations provided information to encourage the girls to consider engineering courses for study; in my case I devised a demonstration to illustrate CAES. |
| Year(s) Of Engagement Activity | 2018,2019,2020 |
| Description | Meeting with ABB |
| Form Of Engagement Activity | A formal working group, expert panel or dialogue |
| Part Of Official Scheme? | Yes |
| Geographic Reach | National |
| Primary Audience | Professional Practitioners |
| Results and Impact | A presentation of mine sparked interest in fluid measurements and metering devices that has led to an on-going discussion in the area. We had a discussion on new "advanced" flow meters, with ABB expressing a significant interest in such a concept. |
| Year(s) Of Engagement Activity | 2014 |
| Description | Meeting with Shell |
| Form Of Engagement Activity | A formal working group, expert panel or dialogue |
| Part Of Official Scheme? | No |
| Geographic Reach | National |
| Primary Audience | Professional Practitioners |
| Results and Impact | A presentation of mine sparked interest in fluid measurements and metering devices that has led to an on-going discussion in the area. Shell requested and now has access to my presentation which has been shared internally; it is being considered further. |
| Year(s) Of Engagement Activity | 2014 |
| Description | Member of the Organising Committee and Plenary Speech at EORCC Conference 2016 |
| 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 | xxx |
| Year(s) Of Engagement Activity | 2016 |
| Description | Member of the Organising Committee and Session Chair ASME-ORC Conference 2015 |
| 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 | Seminal conference on organic Rankine cycle (ORC) technology attended by the vast majority of academics and professionals (industry, end-users, technology developers, component manufacturers, etc.) working this area. |
| Year(s) Of Engagement Activity | 2015 |
| Description | Panel discussion moderation (G3 Energy Summit, London) |
| Form Of Engagement Activity | A formal working group, expert panel or dialogue |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Undergraduate students |
| Results and Impact | This student-organised event had about 150 attendees from a waive-range of backgrounds and involved a number of keynote speeches from a mix of academics and industrialists, plus 3 panel discussions on: 1. Decentralised Energy Technology: Science and Application 2. Decentralised Energy and Development: Contributions, Opportunities and Challenges 3. Decentralised Energy in Mature Markets: Disruption from Decentralisation? I help moderate the third panel discussion. |
| Year(s) Of Engagement Activity | 2017 |
| Description | School visit (Queen Elizabeth's School, North London) |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Local |
| Primary Audience | Schools |
| Results and Impact | Visit to a student to present in lay terms the research that we are doing within my group at Imperial College. This let to questions from the students and schools staff about going university and on the new technologies being developed in our laboratory. |
| Year(s) Of Engagement Activity | 2017 |
| Description | Scientific Committee Member 8th World Conference on Experimental Heat Transfer, Fluid Dynamics and Thermodynamics |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | Yes |
| Geographic Reach | International |
| Primary Audience | Participants in your research and patient groups |
| Results and Impact | Facilitated the event. Was introduced to other members of the scientific committee, who invited me to visit and to present work at follow-on events. |
| Year(s) Of Engagement Activity | 2013 |
| Description | Session Chair 5th International Conference on Applied Energy |
| Form Of Engagement Activity | A formal working group, expert panel or dialogue |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Participants in your research and patient groups |
| Results and Impact | Facilitated the event; chairing led to discussion with presenters and members of the audience. Following this chairing activity, I was asked to forward information on some papers we had published in the area, and asked what our next research directions were. |
| Year(s) Of Engagement Activity | 2013 |