Electricity North West (ENW) received the European Utility Week Energy Revolution Award for its Customer Load Active System Services (CLASS) project – a low cost, innovative solution, which manages electricity demand by controlling voltage.
The solution developed by Electricity North West (UK Distribution Network Operator) in collaboration with National Grid (UK TSO), and assessed commercially by Baringa Partners, has the potential of delivering over 3000MW (or the output of an entire large coal-fired power station) of instantaneous change in demand across Great Britain, and a potential cost benefit of up to £466M to customers.
When rolled out, this solution will be one of the first services for UK DNOs in the transition to Distribution System Operation (DSO) - a key feature of the Energy Revolution.
As we face the challenge of making the transition to a low carbon future, demand for electricity in countries such as Great Britain is set to rise significantly. This will present new challenges to electricity Distribution System Operators (DSOs) like Electricity North West who will need to invest heavily in new network infrastructure to meet this increased demand and accommodate the increased use of low carbon technologies and renewable energy sources. This would be a massively disruptive programme of work and could mean much higher bills for customers.
What is CLASS?
Electricity North West is leading the way in developing smart solutions to meet the UK’s future energy challenges. The company seeks to innovate continuously across its business activities to meet its obligations to customers and respond to their evolving needs and expectations. CLASS was a key project from the company’s innovation portfolio, running from 2013 to 2015, and has helped to establish the company’s reputation as a leading network operator in innovation, providing flexible services at affordable prices.
The project trialled a range of innovative techniques to manage electricity consumption using dynamic voltage control. The principle of this approach is that controls on the distribution substations can vary the voltage at which electricity is supplied to consumers. By adjusting the voltage within the existing operating bands, electricity consumption can be reduced or increased within very rapid response times. By effecting a small demand change on a large number of customers, significant aggregate demand response can be delivered with no discernible impact on end consumers.
The response times of this technique allow it to be used in a number of ways:
- Creating capacity headroom on the distribution network, deferring or avoiding the need for costly reinforcement
- Providing energy reserve services to the System Operator by reducing or increasing demand on instruction
- Providing frequency response services, reacting to rapid changes in system frequency to help the System Operator ensure the security of the system.
The trials have been focused on Electricity North West’s network. However, the technique has been shown to be widely applicable, working with most substation designs, and most customer load types. It is expected that the approach could soon be rolled out nationwide.
CLASS Trials and Technology
Electricity North West worked with the National System Operator (National Grid) to carry out four sets of trials, using a range of equipment installed in the company’s control room and in 60 primary substations serving over 485,000 customers. Thousands of customer surveys were conducted to show that CLASS has no adverse effects on customers’ electricity supply.
To adjust voltage, Autonomous Substation Controllers (ASCs) were installed at the 60 substations and linked to control room management systems and on site automatic voltage control relays. This automatically stabilises the network and keeps voltages at safe levels. An advanced network management system linked the control centre to the National Grid control centre.
The findings from the trials and surveys successfully proved that using CLASS techniques will help meet increasing demand, will make makes it easier to adopt low carbon technologies onto the electricity network such as wind and solar power and does not affect customers’ perception of their electricity service.
The findings also show that if CLASS was rolled out across the whole of Great Britain, the scale of the change in instantaneous electricity demand that could be delivered would be greater than 3000 MW or the output of an entire large coal-fired power station. This flexibility in electricity demand has the potential to radically change the way we keep the entire GB electricity system in balance, minute-by-minute.
Following the success of the original project, CLASS was granted an extension until May 2016 by the industry regulator Ofgem, to demonstrate how the technology could be deployed commercially by DSOs to provide alternative frequency and enhanced reactive power services. DSOs do not currently participate in these markets in GB. By demonstrating how this can be done, and the value this creates for them and their customers, the project will accelerate the implementation of this approach across all DNOs and bring forward the expected £50 million worth of potential customer benefits identified by the original CLASS project more quickly.
[quote] The aim of this market modelling was to determine the benefit to GB customers of a network-led provision of CLASS services to the National System Operator. Baringa Partners carried out this analysis, summarising their findings in a report accompanied by a publicly-available cost benefit analysis tool, developed as part of this work.
Baringa concluded that CLASS has significant potential to reduce the need for the System Operator to use costly and carbon-emitting thermal generators to deliver balancing services. As a result there is significant potential for the CLASS technology to reduce both consumer costs and CO2 emissions. In addition, by delivering more dependable voltage control than is available currently, the net effect of CLASS is an increase in security of supply.
The ability to manage demand through innovative voltage control technology provides a valuable tool for managing the changing requirements of the electricity system:
- Takes advantage of demand flexibility that is already present on the system, and does so with minimal impact on the end consumer
- Increases the ability, and reduces the cost of accommodating increased demand on the distribution network, paving the way for the electrification of heating and transportation required to achieve our carbon reduction targets
- Reduces the need to keep costly and carbon-emitting generation on the system in order to provide energy balancing services, and makes it easier to adopt low carbon technologies onto the electricity network such as wind and solar power
- Reduces the cost of network reinforcement and balancing services, passing the majority of those cost reductions to the end consumer
- Can be rolled out on a national level, working in the majority of network areas, and making full use of existing network assets.