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This project ended in Jan 2019 and is now closed.


Flexible Residential Energy Efficiency Demand Optimisation and Management

Funding mechanismNetwork Innovation Allowance (NIA)
DurationOct 2016 - Jan 2019
Project expenditure5.2 million
Research areaLow Carbon Technologies
  • South Wales
  • November 2019

    Deploying hybrid heat pumps would increase near-term reductions in emissions from buildings and provide greater confidence that very high levels of savings c…


The research objectives of this project are to better understand if hybrid heating systems are technically capable, affordable and attractive to customers as a way of heating homes. This project aims to investigate the feasibility of the use of heat pumps on both WPD’s & WWU’s network in order to:

  1. Demonstrate the ability of the hybrid heating system to switch between gas and electric load to provide fuel arbitrage and highly flexible demand response services; 
  2. Demonstrate the consumer, network, carbon and energy system benefits of deployment of hybrid heating systems with an aggregated demand response control system; and 
  3. Gain insights into the means of balancing the interests of the consumer, supplier, distribution and transmission network when seeking to derive value from the demand flexibility.



The Climate Change Act passed in 2008 committed the UK to reducing emissions by at least 80% in 2050 from 1990 levels. Meeting this target would likely require heat related emissions of CO2 from buildings to be near zero by 2050, both targets pose an enormous economic and environmental challenge to energy providers. In the recent past, the expectation from the government and others has been that gas networks would be switched off within the next 20-30 years, to be replaced by electrified heat. However, it is becoming clear that the electrification of heat brings with it many challenges – both technical and economic. It is imperative that the energy sector support research and invest in energy solutions that are affordable, reliable and safe for our customers.

In the UK, about 70% of all energy consumed is in the home, of which space heating and hot water production account for the bulk of the energy use. With the majority of the homes in the UK being heated by combustion of fossil fuels, a heat generating system that could improve domestic energy efficiency significantly has the potential to deliver dramatic reductions in primary energy consumption and CO2 emissions. 

Electricity is the most expensive fuel available in the UK, an energy savings trust report in 2013 found that rising costs for electricity hit poorer households with electric heating the hardest. Gas boilers typically emit 2-4 tons of carbon per year, depending on boiler and house type. Converting 10,000 homes to hybrid heating could save between 10,000 and 20,000 tonnes of carbon per year. The hybrid heating system has the potential to help meet the EU’s ambitious environmental targets of achieving a 20% cut in greenhouse gas emissions compared with 1990 levels and a 20% reduction in energy consumption by 2020. The technology, which combines domestic gas boiler and air-source heat pump heating, has the capability to use either fuel or both and can be used as fully flexible loads capable of providing significant energy system value. 


PassivSystems Limited and its partners have put together a proposal to deliver a technically and commercially successful innovation project to realise the benefits of using the hybrid heating system (heat pump and gas boiler) for our networks and our customers. The success of the work will depend largely on the location, housing types and type of heat pump. The trial will be conducted in domestic housing units in the Bridgend area to demonstrate potential solutions to the findings of earlier research projects such as Bridgend Future Modelling. A variety of liaison meetings between PassivSystems and the Local Authority as well as other interested organisations, to gain the support and ensure the deployment satisfies the given criteria, has been undertaken. 

The methodology for the delivery of this Project will follow the process below: 

  1. Selection of the area for the trial (customer engagement plan) 
  2. Selection of the type and size of the heat pump 
  3. Modelling 
  4. Mobilisation (procurement of equipment and services) 
  5. Trials or field test, including measurements (install equipment) 
  6. Connection agreements and policy 
  7. Analysis and close down (Analyse results, evaluate)