The challenge

As the UK electrifies transport and heating, demand for electricity is expected to grow significantly. At the same time, increasing volumes of renewable generation create a need for more flexible energy consumption patterns.

Traditionally, the electricity system has relied on generation assets to balance supply and demand. However, future network costs could rise substantially if flexibility is not unlocked from consumers. A key challenge has been the lack of evidence that domestic flexibility can be delivered reliably and forecast accurately at scale.

There is also a risk that the benefits of flexibility markets are concentrated among households with electric vehicles and smart technologies, leaving others behind.

The solution

Led by NESO, CrowdFlex brought together energy suppliers, network operators, technology innovators, and research organisations to test domestic flexibility through large-scale trials in which more than 140,000 customers participated.

The project explored flexibility in two types of trial:

• utilisation trials where households were rewarded for manually shifting electricity demand up or down during specific periods
• availability trials where EV owners were rewarded for making automated flexibility available by plugging in vehicles more regularly

Evidence from the trials was used by CrowdFlex to develop two forecasting tools that enable system operators to predict both the amount of flexibility available and the probable level of response likely to be delivered during an event.

A customer survey respondent said “I do my washing in the early hours or overnight most of the time but sometimes when the laundry is waiting and there’s a power move, I say oh,
why not? Let me just do it in this one hour, if that’s the time. So yeah, I’ve
learned that I can be flexible.”

Moving through the stages of SIF

With support from the SIF phased approach, from 2022 to 2026 CrowdFlex progressively narrowed its scope from exploring the potential of domestic flexibility to proving its real-world value.

In the initial Discovery phase, the project focused on understanding system operation and distributed network operation requirements and assessing the feasibility of domestic flexibility services.

The subsequent Alpha phase translated these broad requirements into a practical trial design, reducing the focus to a shortlist of viable flexibility services and consumer incentive approaches.

By Beta phase, the project concentrated on delivering and evaluating large-scale trials, primarily focused on EV charging and demand response, testing a small number of payment mechanisms and targeted customer segments.

Delivering flexibility at scale

The project used large-scale randomised controlled trials to understand how consumers respond to different incentives, notice periods and engagement approaches. More than 37,000 survey responses and extensive consumer research helped ensure the findings reflected the experiences of a wide range of households, including vulnerable customers.

Testing took place in real-world conditions using customers’ own smart technologies and devices. This provided valuable operational evidence, including findings that automated flexibility solutions helped participants shift around 30% more electricity compared with manual participation. 73% of availability participants said flexibility became part of regular habits.

Impact and benefits

CrowdFlex demonstrated that domestic flexibility can be forecast and utilised more reliably than previously understood, providing confidence that it can play a meaningful role in future system operation.

Key outcomes include:

• development of forecasting models capable of predicting household flexibility with greater accuracy than traditional approaches, enabling control rooms to utilise this flexibility more
• analysis suggests that domestic flexibility could deliver an estimated £1.6 billion net present value by 2050, driven by reductions in balancing costs
• evidence that participation can be attractive across a wide range of households, helping ensure flexibility markets are accessible and inclusive

The project also showed that collaboration between system operators, energy suppliers, technology providers, and network companies can successfully unlock distributed flexibility at scale.

Building the future flexibility market

A significant outcome of CrowdFlex is the evidence base it provides for future flexibility markets. By reducing uncertainty around the reliability of domestic demand response, CrowdFlex helps pave the way for new market arrangements and operational processes that make greater use of household flexibility.

The forecasting models developed through the project are now being transitioned towards business-as-usual deployment within NESO, with plans for further integration into future system operation and market platforms.

The CrowdFlex trials have demonstrated that Ohme’s smart EV charging technology has a crucial role to play in domestic flexibility and in reducing
energy costs for consumers and the system alike.

Our customers showed they are willing and able to shift their plug-in
behaviour when incentivised to do so and, crucially, they responded positively
to a range of different approaches, from escalating financial payments to
simple behavioural nudges. Automated smart charging proved particularly powerful, enabling customers to deliver flexible capacity with minimal effort on their part.

CrowdFlex has helped build the evidence base that domestic flexibility could deliver hundreds of millions of pounds in system benefits annually as EV uptake accelerates and Ohme is proud to have contributed to laying that
Foundation.

– David Watson, CEO, Ohme

Project partners

CrowdFlex was led by NESO and delivered in partnership with:

• OVO Energy
• Ohme EV
• Centre for Net Zero
• ERM
• Amazon Web Services (AWS)
• National Grid Electricity Distribution
• Scottish and Southern Electricity Networks

Support was also provided by:

• Centre for Sustainable Energy
• The Smith Institute
• CGI
• Smart Grid Consultancy

The Ofgem Strategic Innovation Fund is an Ofgem programme managed in partnership with Innovate UK.