Written evidence submitted by Pembrokeshire County Council (DHH0093)

Pembrokeshire County Council are currently leading on the Innovate UK funded Milford Haven : Energy Kingdom (MH:EK) project MH:EK is a two-year £4.5 million project, completing in 2022, exploring what a decarbonised smart local energy system could look like for the Milford Haven Waterway. The project will explore the potential of hydrogen as part of a multi-vector approach to decarbonisation. The project is multi-faceted and will see the team investigate local renewable energy, including solar, onshore wind, future offshore wind and biomass for decarbonised gas transition; diversified seed markets for hydrogen across buildings, transport and industry; consumer trials of fuel cell vehicles and hydrogen-ready hybrid heating systems. Graphical representation of the MH:EK Detailed design & potential future implementation:


One of our Partners in MH:EK are Wales & West Utilities (WWU) who have a central role in the energy system and are experts in the field of whole energy systems engineering. Part of this expertise has come from the development of the Pathfinder energy system simulator a unique tool amongst electricity and gas distribution operators. Our responses have been drawn from evidence from both Pathfinder and other research commissioned by Wales & West Utilities into the area of heat decarbonisation as part of a whole energy system.

In the context of this whole energy system there is no one size fits all approach; however we believe there is one area that has been overlooked by most of the evidence provided to-date – that of smart hybrid heating systems.

Smart Hybrid Heating

Pembrokeshire CC think that the example of the WWU / Western Power Distribution Freedom Project provides a strong case for the use of smart hybrid heating systems which can switch optimally between gas or electric heating considering weather conditions, time of use and costs of fuel. https://www.wwutilities.co.uk/media/3859/freedom-project-briefing-document.pdf.

Compact ‘all in one’ hybrid boilers are now available combining a gas boiler and a heat pump in the same appliance that’s very similar in dimensions to a standard boiler making retrofit simpler with quality controlled factory based production. Smart controls are critical for this type of heating.

The Energy Networks Association and Navigant have produced a report, Pathways to Net-Zero: Decarbonising the Gas Networks in Great Britain, which concludes that a balanced combination of low-carbon gases and electricity is the optimal way to decarbonise the UK energy system and reach net zero emissions by 2050.

Enquiry questions and answers

What has been the impact of past and current policies for low carbon heat, and what lessons can be learnt, including examples from devolved administrations and international comparators?

Subsidy support for biomethane has led to significant uptake particularly in certain geographical areas such as SW England. Subsidies for renewable electricity are higher than for heat, so over 50% of biogas sites just produce electricity rather than using the green gas for heat or transport/ storage and grid balancing – heat/transport being areas UK is struggling to decarbonise currently.

What key policies, priorities and timelines should be included in the Government’s forthcoming ‘Buildings and Heat Strategy’ to ensure that the UK is on track to deliver Net Zero? What are the most urgent decisions and actions that need to be taken over the course of this Parliament (by 2024)?

A hybrid heating first’ policy, as recommended by UKCCC, would enable an efficient whole energy system approach to decarbonise electricity and heat grids. An emerging ask of the Milford Haven : Energy Kingdom project that could apply nationwide is that Government mandate only hydrogen-ready boilers and hybrid heating systems by 2025 which would add little/no additional cost and ensure boilers are ready for a decarbonising gas grid.

Which technologies are the most viable to deliver the decarbonisation of heating, and what would be the most appropriate mix of technologies across the UK?

  1. Energy efficiency
  2. Heat networks in certain locations with the correct attributes.
  3. Smart hybrid heating systems, including compact hybrid boilers, using renewable electricity and green gases
  4. Off-gas solutions could include heat pumps and hybrids with bioLPG.

What are the barriers to scaling up low carbon heating technologies? What is needed to overcome these barriers?

Skills, but for home heating, the compact hybrid boiler ‘first’ proposal can eliminates the skills challenge by fitting all-in-one hybrid hydrogen ready heating systems.

‘Hard-to-heat’ properties cannot efficiently, cost effectively or satisfactorily use with an air source heat pump alone.

How can the costs of decarbonising heat be distributed fairly across consumers, taxpayers, business and government, taking account of the fuel poor and communities affected by the transition? What is the impact of the existing distribution of environmental levies across electricity, gas and fuel bills on drivers for switching to low carbon heating, and should this distribution be reviewed?

Use the lowest life cycle cost, least regret pathways:

What action is required to ensure that households are engaged, informed, supported and protected during the transition to low carbon heat, including measures to minimise disruption in homes and to maintain consumer choice?

The least ‘painful’ solution where users can generally carry on with minimal disruption or change to ‘the norm’ is desirable for mass uptake and acceptance. Hydrogen-ready boilers and compact hybrid boilers eliminate disruption and keep costs to the minimum, maintaining a familiar system to the one that consumers currently have.

Where should responsibility lie for the governance, coordination and delivery of low carbon heating? What will these organisations need in order to deliver such responsibilities?

Energy networks.


Local authorities (with financial support) can provide significant roll out of low carbon heating systems into retained social housing stock. Pembrokeshire CC, for example, has 6000 retained council houses out of circa 55,000 total households in the county. This is replicate in local authorities across the UK.


December 2020