The National Physical Laboratory (NPL) is supporting a net zero energy grid

Scientists at the National Physical Laboratory (NPL) are working with industrial partners to develop and deliver the next generation of measurement techniques to support the electricity grid in achieving net zero targets.

NPL is developing, testing, and validating new inertia measurements methods, and reference techniques, required to underpin stability and control in the net zero grid, and working with National Grid ESO (NGESO) to evaluate the accuracy of commercial inertia measurement systems being implemented. Developing and validating measurement methods for inertia, to provide confidence to UK operators in their adoption, supports security and efficiency in energy supply with increasing renewable energy sources.

To meet net zero objectives, unprecedented levels of intermittent renewable energy sources will need to be connected to the British grid. For power system operators, one of the biggest technical challenges to achieving net zero is the decline of grid inertia which needs to be effectively managed to ensure continued stability and reliability of the power system. Traditionally, power system operators have relied on inertia provided by fossil-fuelled synchronous generators to prevent frequency excursions that can trigger grid instability.

Another issue which could limit progress to net zero is the interference and disturbances that can affect connected equipment. Net zero technology such as renewables, EVs, High-Voltage Direct Current (HVDC) and energy storage require power convertors which inject disturbances into the power system. These disturbances can impact protection systems, grid assets and equipment, and domestic appliances.

Network operators need new measurement methods to identify and quantify the prevailing interference levels to manage and mitigate them and maintain supply quality and reliability to allow the grid to safely host the essential net zero technologies. Pro-actively investigating mitigation methods will ensure issues do not become more wide-spread and impact consumers. Internationally there is currently no standardisation on how to perform these types of measurements.

NPL has led a European normative project (SupraEMI), which has developed and proposed measurement algorithms for associated international standardisation, providing a clear understanding for development of disturbance measurement capabilities in the UK and guidance to industry.

In collaboration with an industry steering group of experts, NPL is developing a new measurement system, accreditation-ready test rigs, and on-site survey capabilities, to support new British grid codes and enable mitigation action and grid planning to overcome issues associated with the injection of these disturbances.

NPL research on inertia and disturbance measurement supports the development of measurement infrastructure to underpin the deployment of new technologies, operational procedures and novel practices to reach stable and reliable net zero grids.

Ben Rowton, Strategic Business Development Manager for the Energy and Environment sector at NPL says: “A net zero future requires increasing the levels of renewable energy sources and low carbon technologies connected to the power grid. NPL’s expertise in developing novel measurement methods and testing standards means we are in an excellent position to support network operators, equipment manufacturers and regulators, to ensure security of supply whilst the UK adopts and deploys innovative products, services and unique operating models.”

Julian Leslie, Head of Networks at National Grid ESO, comments: “Our investment in world-first inertia measuring tools and pioneering green engineering projects is helping us to operate the fastest decarbonising electricity network in the world.

“As more renewable energy sources connect to the network, our work with NPL will help explore how we can improve the management of system stability to enable us to operate a zero-carbon grid by 2025.”

Francis Mosley, Senior Innovation and Systems Engineer at Ofgem, says: “Ofgem’s objective is to help deliver a net-zero economy at the lowest cost to consumers. The work NPL is delivering to enable the transition to a sustainable energy system, particularly in developing the next generation of measurement techniques, plays an important part towards meeting net zero goals.”