Affordable and clean energy via resilient and autonomous micro-grids

The rising integration of distributed renewable energy resources (DERs), i.e. renewable energy systems, energy storage systems and active loads, to the power grid has increased the need for decentralised power network infrastructures utilising distributed generation and storage in a local and autonomous manner (micro-grids). Since DERs suffer from increased volatility in the supply (renewable energy systems) and demand (consumer behaviour), the key challenge is to achieve a reliable, stable and resilient operation of modern micro-grid systems in order to provide clean and cheap energy to both power producers and consumers (households, businesses). The solution to this challenge is hidden in the 'control design of DERs'. A decentralised control approach for DER units that operates with minimum communication under both normal and abnormal conditions (faults, unit disconnections, loss of communication) will significantly increase system resilience and pave the way towards a new generation of micro-grids, where clean energy will be utilised at a cheaper price within the premises of a local community of producers and consumers.

The aim of this fellowship proposal is to develop a novel control engineering approach for maximum utilisation of DERs in a local community-type micro-grid architecture based on the unique 'bounded integral control' methodology that can rigorously prove nonlinear stability of the entire micro-grid system. Using a private power network infrastructure that links producers and consumers of a local community (neighbourhood) with central and local storage units behind the meter, new Peer-to-Peer (P2P) energy-trading opportunities will be generated via this community-type micro-grid, leading to at least 20% financial benefits for every community member. The resilience of the system will be guaranteed via the advanced control technologies for the power converter-fed DER units, which will rigorously guarantee a stable and reliable micro-grid operation in a decentralised manner (minimum communication requirements). Both fundamental and applied research will be generated by the proposed research, i.e. the generalised bounded integral control theory with nonlinear stability analysis for micro-grids, and novel decentralised control technologies for integrating DERs.

Due to the interdisciplinary nature of the proposed approach that combines 'control' and 'power' engineering research areas, the fellowship will lead to the development of a strong and sustainable research group that will produce world-leading research and technological solutions in the areas of control systems, micro-grids and smart grids directly aligned with the UK industrial strategy of 'cheap and clean energy technologies'. Based on the strong industrial (Infinite Renewables, Crossflow Energy, Yokogawa, OPAL RT) and academic support (Prof J. Guerrero from Aalborg University), and building on the existing links of the industrial partners with UK Housing Associations, suitable sites (e.g. new-build communities) will be identified to implement the proposed technology and generate the first autonomous community-type micro-grid in the UK.

The impact goals of this research are to:
- Provide evidence that intelligently controlled community-type micro-grids with a private power infrastructure and central energy storage pool can provide clean energy to every community member (producer, consumer or both) at a reduced cost;
- Develop advanced control methods for integrating power converter-fed DERs that operate with limited communication requirements in micro-grids and can rigorously guarantee the stability and resilience of the power system;
- Recommend control techniques that will enhance system inertia and support the grid during faults (fault-ride-through) to National Grid and DNOs in order to rethink policies and intergration requirements for DERs - this will lead to large-scale utilisation of renewable energy systems;
- Design P2P energy trading optimisation algorithms with online price and contract adjustment aiming for at least 20% financial benefits to every community member;

The impact of the proposed research to the academic community is high since researchers from both areas of 'control theory' and 'power systems' will benefit from: i) the development of a novel fundamental bounded integral control theory and the nonlinear stabilisation of micro-grids and ii) the design and implementation of a resilient community-type micro-grid infrastructure that utilises clean and cheap energy within the premises of the local community. This academic impact will be maximised due to the collaboration of the with the leading research group of Aalborg University in the area of micro-grids led by Prof. Josep Guerrero (one research visit to Denmark per year has been planned), which will lead to high-quality research publications in top-rated journals of control and power systems.

Due to the strong industrial support, the proposed research will lead to high industrial impact since Infinite Renewables Ltd (industrial partner) has strong links with UK Housing Associations (Pennaf), which are currently looking into community micro-grids. The new-built housing community development at Plas Telford, Acrefair, Wrexham, represents one of the several sites for the case study of this research. The advanced control methods that will be developed for power converter-fed units will be integrated and retrofitted into existing renewable energy schemes in addition to new developments. The community-type micro-grid will enable each individual community member to benefit from increased energy production and generation revenue and a reduction in on-site power costs. Wider impacts of this project and possible stakeholders include:
- Benefits to housing communities. The research from this fellowship will enable direct exchange of energy between community members allowing generators to sell energy in a higher price compared to current Feed-In Tariffs and consumers to use energy in a lower cost compared to the £/kWh energy consumption cost.
- Addressing fuel poverty. Housing Associations (e.g. Pennaf) are very keen to utilise the system and get involved in pilot projects to help tackle fuel poverty and reducing energy costs which would be achieved at a "local" level.
- Contribution to legislative requirements. The Renewable Energy Directive requires 20% of total energy needs to come from renewables by 2020. This project will contribute by creating enabling technologies that will extract greater efficiency from renewables and will contribute to the grid stability.
- Contribution to industry standards. The British Standards Institute (BSI) has several renewable energy technical committees working on developing standards. Outcomes of this fellowship will support BSI to explore the creation of a new industry standard or Code of Practice for community-wide micro-grids.