Projects

Completed

Applied Research and Development

ENGINEERING AND TECHNOLOGY (Electrical and Electronic Engineering)

Not Cross-cutting

Project Contact
Electricity North West Limited

Network Innovation Allowance

Ofgem

01 August 2025

28 February 2026

ENA months

£154,205

Power

North West

Network Innovation Allowance

Project Contact, Electricity North West Limited

Variable rating is a new tool being developed in Cool Runnings to provide near real-time ratings for distribution transformers that vary with ambient temperature and substation environment. As the variable rating will be higher in cooler ambient conditions, additional capacity can be released in winter when it is anticipated that heating load will be at its peak. Therefore, this tool is specifically suited to managing the increased demand associated with HPs.This project will focus on developing the methodology (including specialist temperature measurement techniques) and designing the test schedules to enable physical transformer testing in the next stage of the project. This project will: Prove the technical capability of distribution transformers to support loading up to a calculated variable rating. Update and validate the Smart Heat Variable Rating approaches using experimental data and an understanding of the likely BAU implementation. Understand the work, tools, processes, and changes in thinking needed in ENWL and the other GB DNOs for BAU implementation, and the fit of this method alongside emerging new technologies and approaches. Scope and specify the required next steps, including the detailed scope for a Phase 2 project.As a part of the Smart Heat NIA Final Project Report, a Cost Benefit Analysis (CBA) was conducted for the Smart Heat solutions which indicated that the Smart Heat Variable Rating solution has significant financial and carbon benefits over alternatives, including traditional reinforcement and alternative smart solutions.The CBA (2022 figures) indicates that implementing the Variable Rating solution alone would provide an estimated financial benefit of 127.4m, as well as 30ktCO2e in carbon benefit above the traditional base case (current BAU), that is up to 2050 over the Electricity North West network region. The objective of this project is to scope out testing of distribution transformers, which will include definition of the test requirements and a detailed test plan. Scoping of Testing: develop written requirements, scope and deliverables for Distribution Transformer testing. This will include an exploration of transformer monitoring options, which builds on ENWLs initial investigations (from previous innovation projects), definition of test requirements and definition of detailed test plan. This will include a review of previous data to understand the baselining needed in order to develop variable rating equations. Develop Initial Variable Rating Method: Investigation into Variable Rating algorithm in advance of trial testing. Areas to understand is the quantity of data needed during initial testing to characterise the transformer into the algorithm. Another point to consider is the type of load profiles to apply during initial testing to acquire enough data to understand the relationships between hotspot and surface temperature Develop initial template for Variable Rating Tool: Develop an initial template of what the Tool will look like. Initial Scoping of Tools and Process Changes: Initial view into how this process would integrate into BAU solution architecture.

Cool Runnings will explore the technical and practical implementation of the Smart Heat Variable Transformer Rating method. The Smart Heat NIA project investigated different approaches to manage the impact of network overloads due to the increase in network demand caused by the uptake of heat pumps (HP). Cool Runnings will investigate the extent to which capacity released by applying variable ratings in distribution transformers, can support the additional load from HP uptake for various network designs (building type; transformer size, age, design) and ambient conditions. This phase of the project will develop an initial variable rating algorithm and define the laboratory testing required to prove it which will be conducted in future phases.

24/04/26