Generation Integrated Energy Storage - A Paradigm Shift

This project will assess a class of systems that blend electricity generation and storage, to understand the role that they could play in future energy systems. Their ability to deliver low-carbon energy on demand, at low system cost, will be investigated from technical, economic, and policy standpoints.

With a growing fraction of electricity consumption being supplied by variable renewable energy sources, the ability to match energy generation and energy consumption is rapidly taking centre stage. Flexible ('dispatchable') coal and gas plants are being displaced to lower carbon emissions. At present, both nuclear and renewable energy technologies are generally configured to generate as much electricity as possible, regardless of the electricity demand at the time. Standalone energy storage, in which surplus electricity is converted to an intermediate energy form and then back again, is emerging as a vital partner to these generation technologies but it is prohibitively expensive for the duties that will be required in the near future. Active management of electricity demand (by shutting down or deferring loads) and electrical interconnections with neighbouring countries will also play important roles but these also have costs and they will not obviate the need for storage.

This project will build a deep understanding of a class of system which takes a different and potentially much lower cost approach. These Generation Integrated Energy Storage (GIES) systems, store energy in a convenient form before converting it to electricity on demand. The hypothesis is that the lowest cost and highest performance storage can be achieved by integrating generation and storage within one system. This avoids the expense and inefficiency of transforming primary energy (e.g. wind, solar, nuclear) into electricity, then into an intermediate form, and later back to electricity. For example, the heat produced by a concentrating solar power plant can be stored at far lower cost and with lower losses than producing electricity directly and operating a standalone electricity store.

A broad range of opportunities exist for low-carbon GIES systems, in both renewable and nuclear applications. The research team's expertise in wind, nuclear, and liquefied air storage will be applied directly to GIES systems in all three. The project will also establish a framework for the wider significance of GIES to energy systems. Technical and thermodynamic metrics that characterise high performing GIES systems will be developed, and used to compare with standalone generation and storage equivalents. The theoretical groundwork laid by this research will have applications far beyond the current project. Opportunities for current and future technologies will be mapped out and publicised, supporting and accelerating further work in the field. The deployment and operation of such technologies will be modelled by means of a pragmatic real options economic analysis. The unique policy and economic considerations of fusing generation and storage will be reviewed in detail, considering challenges and proposing solutions to regulatory and financial hurdles. Taken in concert, these will determine the value and scope for substantial deployment of GIES systems.

In bringing to light the potential of the class of GIES systems, the research team will rectify a gap in energy systems thinking, in time to inform what will be a multi-billion pound expenditure in the coming decade. By providing the tools to analyse and deploy these systems, the research will open up a new avenue for cost-effective flexibility across the energy infrastructure of the UK and other regions worldwide.

Our research and analysis will show how Generation-Integrated Energy Storage (GIES) systems can make an invaluable contribution to the continued deployment of low carbon generation up to high penetration levels. Integrating a small fraction of inflexible low carbon generation into our energy system has been comparatively easy because the remaining fossil-fuelled generation could be flexed to balance supply with demand. Each additional 10% becomes more difficult and even the commitment to draw 30% of electricity from renewables by 2020 will bring major balancing challenges.

The 2016 report by the Carbon Trust and Imperial College suggests that savings associated with introducing energy storage into the UK system could be between £2.4bn and £7bn per year by 2030. These estimates were based on received values for the costs and performance of energy storage in standalone systems like pumped-hydro and simple compressed air plant, flywheels, batteries and isolated liquid air systems. We expect to show that very substantial quantities of storage can be implemented in "GIES mode" with high performance and exceptionally keen cost. We expect, as a result, to show that the system savings can be significantly higher and to play some small part in seeing these benefits realised. A natural consequence will likely be that higher penetrations of low carbon generation will be adopted than would otherwise be the case.

Specific stakeholders in the public and private sectors will benefit from the project:

- In the private sector we will make the case for technology development in a relatively new application area, where energy storage is integrated with power generation. Most emphasis thus far has been on energy storage which stands apart from generation. Whilst recognising that this (standalone storage) is an extremely important area that will inevitably see enormous future growth, there is the potential that GIES systems will have a similar destiny starting from almost-zero at present. The project will bring a completely new set of players into the energy storage market - parties presently focused on low-carbon generation of various sorts.

- For the public sector, our analysis of the value of GIES will inform the development of future energy system pathways, assessing how this new class of technologies can increase the efficiency of the energy system in the transition to low carbon. We will also describe the barriers to its deployment, providing recommendations for policy-makers that will help ensure its potential is reached.

We will achieve this impact from a combination of approaches:

- Engagement with a panel of industrial participants committed to supporting the project and with a network of prestigious international universities who recognise the potential that GIES approaches can be transformative.

- Wide stakeholder workshops over the course of the project to draw in the expertise of the energy sector from across policy, industry and academia.

- Direct interaction with the energy community through formal interviews, participation in external workshops/conferences/meetings, and through links with networks such as the Energy Storage Supergen Hub.

- Dissemination of emerging and final results through peer-reviewed academic papers, more accessible reports and policy briefings, and presentations at relevant events.