Project Summary
Aim: REWIRE will explore the technical viability and economic benefit of integrating vector conversion and energy storage technology at a domestic level to increase whole system resilience.
Whole system resilience: The energy system’s ability to recover from disruptive events will be significantly improved with the integration of localised storage, provided by REWIRE’s multi-energy systems.
Context: The challenge of whole system energy balancing will grow with increasing penetration of intermittent renewables, with 50GW of offshore wind predicted by 2030, and 40GW of embedded distributed generation in the form of domestic solar predicted by 2050.
Growing electrification of residential transport and heat further increases the likelihood of system imbalances. The role of hydrogen as an option for decarbonising heat remains uncertain, with domestic demand forecasts ranging from 145 to 0 TWh, potentially leaving infrastructure redundant.
Additionally, climate change and geopolitical instability are increasing the likelihood of extreme weather and infrastructure attacks, respectively, further impacting system resilience.
Specifically, two scenarios – low wind, low solar at peak demand and low demand, high renewable generation – would cause resilience issues on a decarbonised national grid, with the latter incurring costs for generation reduction.
Solution: REWIRE is a domestic cross-vector storage system, exploiting power-to-gas and gas-to-power technology with integrated local hydrogen storage. REWIRE brings benefits for consumers through improved energy security, and for networks as a fast-response flexibility service provider.
The solution will alleviate network constraints by increasing availability of flexibility services for demand electrification, reducing reinforcement and system balancing costs. Additionally, low-pressure gas network infrastructure could be used for transporting hydrogen to point of use or as local energy storage, optimising the use of existing resources. This would enhance utilisation of existing assets, producing net cost benefit for networks and consumers.
Project Partners:
- Electricity North West Limited (ENWL) is lead partner and will lead WP2, using their understanding of consumer requirements to rank network archetypes based on their requirements for improved resilience.
- Imperial College London will lead WP3, applying their world-leading whole-energy system modelling expertise to analyse the resulting techno-economics and cost benefits.
Subcontractors:
- Frazer-Nash Consultancy will lead WP1 and WP4, using their experience of network innovation projects to assess the factors affecting implementation of REWIRE.
Cadent Gas Distribution Network have committed to joining the project in Alpha Phase. Their experience with gas network operation and future hydrogen transition activities makes them an ideal partner to aid the assessment of gas network integration.
Innovation Justification
Problem: Decarbonisation of the power system with increasing generation from intermittent sources and growing demand from electrified domestic heating and transport means that maintaining future network resilience will require costly and labour-intensive network reinforcement. Additionally, vast quantities of low-cost renewable energy is curtailed when demand is low, indicating a requirement for significantly increased energy storage. GB has an extensive gas pipeline network, which many studies suggest will be largely redundant at low pressure tiers by 2050. The use of this infrastructure may help to increase resilience whilst reducing the need for reinforcement of local electricity networks.
Novel approach, overcomes knowledge gaps: Previous work focussed on decarbonising domestic demand through electric heat pumps or substituting natural gas with hydrogen rather than considering a combination of gas and electricity systems that could also support network resilience. Building on work to review domestic heating technologies by Imperial College, REWIRE will provide new research on the benefits of, and necessary adaptations for, installing hydrogen tanks, electrolysers, fuel cells and hybrid heat pumps at a residential level for varying domestic archetypes.
Risk: There are technical and regulatory barriers associated with using this solution in domestic properties and how it interfaces with network operation. High risk areas to be explored include the operational feasibility, funding and owning of assets, commercial feasibility, safety, and societal preconceptions.
Value: A cost benefit analysis will be undertaken to understand the economic benefit of improved resilience and optimised utilisation of gas and electricity infrastructure through the use of domestic level combined green hydrogen. This economic review will assess network reinforcement, gas network decommissioning and curtailment of renewables as appropriate counterfactuals. Effective valuation of the benefits will include monetisation of resilience, most appropriately expressed as Value of Lost Load (VoLL), which incorporates asset losses, perishables, business interruption costs, and recovery costs.
Sustainability benefits shall be valued as equivalent carbon emissions, versus equivalent counterfactuals such as fossil fuels, and how the reduced requirement for reinforcement may accelerate the electrification of heat and transport.
Strategic Innovation Funding: This project aligns with SIF as it is a novel and high-risk exploration of an approach to improve system resilience, whilst offering consumers opportunities to engage with the market and increase personal energy security. There is clear progression towards a Beta demonstration project, with potential to pilot the technology in a local network region.
Project Benefits
Network operating costs: The additional storage and flexibility available from the REWIRE system improves network system resilience and balance and mitigates network reinforcement.
Consumer bills: In 2021 the Electricity System Operator spent £143 million curtailing 2.34 TWh of wind energy; REWIRE would avoid this curtailment, reducing consumer bills.
Domestic level energy storage forms part of the REWIRE system and will help consumers shift energy demand to when costs are cheapest and national demand is lowest, if using a flexible tariff, thereby reducing their bills.
There is also potential for consumers to engage with the flexibility services market, increasing their revenue and reducing average energy consumption costs. These benefits can be amplified through optimisation of the vector conversion based on economics and real-time market conditions.
REWIRE will maximise utilisation of existing assets, e.g. by using the gas distribution network for localised energy storage, reducing costs for both networks and consumers.
Direct CO2 savings: REWIRE can directly affect carbon emissions by avoiding curtailment of renewable generation. Without REWIRE, if 50 GW of offshore wind is installed by 2030, with capacity factor of 40% and curtailment rate of 14%, nearly 25 TWh could be curtailed per annum – equivalent to 7.61 MtCO2e from natural gas generation.
Additionally, using electrification or hydrogen for heating through REWIRE would result in significant carbon benefits as it will replace natural gas. According to Ofgem, the average domestic property uses 12 GWh of natural gas per annum, which equates to roughly 2.19 tCO2e per property.
Indirect CO2 savings: REWIRE can also save carbon by accelerating the rollout of low carbon technologies, due to reduced reinforcement requirements and reduced emissions associated with system losses through storage of domestic and locally generated energy.
Revenues: domestic consumers will have improved access to revenue through the provision of flexibility services. There is potential for creation of new markets and flexibility services relating to domestic hydrogen injection to the low-pressure network for distribution or storage.
Additional benefits: Consumers in vulnerable situations, particularly those who require constant supply for medical equipment, will benefit from increased security of supply.
Properties without connection to the gas grid can produce and store hydrogen for domestic use or fast-response power generation, increasing their choices.
The metrics required to quantify these benefits will be defined in the Discovery phase, but will predominantly be avoided costs of curtailment and reinforcement, which are calculated via standard CBA counterfactuals.
