Decarbonising heat: The road to net zero

road to net zero
© Anna Nikonorova

Pete Mills, Commercial Technical Operations Manager for Bosch Commercial & Industrial, describes the challenges and vast opportunities when transitioning to decarbonised heating systems in the UK

A time of transition is upon us. Anyone who needs to provide heat to keep our families, our employees, those who need care or those who need heat to produce things, must sooner or later consider how that heat will be generated in the future. If you are the person responsible for any of the above, chances are you have seen or heard something about the future of heat, or to be more precise, decarbonised heat.

Like all transitions, it could be a troublesome time, especially when direction from Government is not yet fully transparent. Pressure mounts as carbon reduction targets are agreed and local Governments declare climate emergencies. Now, I do not think I would be talking out of turn if I were to say that many of those responsible for transitioning heating systems to decarbonised forms are starting to feel some pressure.

Up to now the carbon reductions achieved by the UK have been largely made in areas that affect individuals very little, if at all. The significant carbon reductions achieved through renewable energy such as offshore wind farms have not meant significant changes to people’s homes and businesses. However, once the low hanging fruit has been picked, we must tackle the difficult ones and heat by any measure will be a challenge.

Over the last decade or so, the direction and purpose of energy-related regulation has been focused around energy efficiency. Targets were incrementally raised to their technical maximum for products, to promote a reduction in overall energy use. The main thrust of Government grants and funding was focused on improving thermal performance of buildings, as well as supporting early adopters of renewable heating technology. That reduction in energy use is still particularly important and is often these days referred to as a “fabric first approach”, meaning let’s do what we can to reduce heat loss before we tackle anything else.

In the UK, we have possibly one of the most diverse portfolios of building types due to our rich heritage. The thermal performance of these buildings covers the entire range of possibilities, with every type of architecture and building code represented. Approximately 80% of the buildings we will have come 2050 are already built and with us today. This makes a one-size fits all approach unrealistic. Now, that is a simple statement, but it means we must have the grid supply options available if we are to treat the bulk of existing buildings.

There is much debate about electricity versus gas, which must leave most responsible for transitioning existing heating systems none the wiser. The debate though is starting to shift to one more focussed on whether consumers will have a choice in the matter or whether there will be central direction restricting what we can do. Having a choice means having real options available to us at the time we must make, what will be for many, a significant decision. This means firm Government commitment to transitioning the gas grid to hydrogen as well as reinforcing the electrical grid to cope with increased demand from both heat and transport.

Central direction could mean that not only must we transition our heating systems within a certain time aligned with carbon budgets, but also that the choice of technology could be dictated. That for many of us is a troubling thought and has at its heart some fundamental political implications.

So, what is available to us now if the pressure is on and action is needed? My view is that this next five years is a critical time for heat pumps to show whether or not they can be applied at the scale needed and to the variety of building types, we have in the UK. Not only this, but they must gain consumer acceptance both in initial affordability and running cost. Government have set a challenging target of 600,000 heat pumps a year by 2028. For sure, heat pumps have a big part to play in new build, where heating systems can be made from scratch to optimise the operation and efficiency.

Hybrid systems

Hybrid systems have been identified by the Committee on Climate change as having significant potential. Here heat pumps are coupled with condensing gas boilers to meet the annual heat demand profile. Heat pumps typically pick up the base load, whilst the gas boilers kick in to meet the higher demands during the winter. For full net zero carbon, this will need the eventual decarbonisation of the gas grid, which looks to begin with hydrogen blends to 20%, followed by a transition to 100% hydrogen.

Hybrid systems are particularly useful for commercial heating systems, providing significant capital savings where heat pumps are sized around 40% of the peak demand. In the future once gas decarbonisation is complete, there is flexibility to load shift from one energy vector to another, which could have significant benefit to the networks as a whole. This builds in some future proofing and maintains consumer choice for years to come.

Heat networks too have great potential, especially where waste heat sources are available. To realise the full potential, transforming into true district heating will need coordination from Local Authorities in particular, to join individual systems into larger ones. On the face of it, being locked into a single system to provide heating and hot water might seem to restrict consumer choice. However, there is plenty of evidence from across Europe, where heat networks have consistently delivered good value heat, that consumers are happy. The challenge for the UK industry is to mirror this success to ensure consumers get the affordability and service they deserve.

To deliver these changes will need good availability of the skills required to design and install well-chosen decarbonised heating systems. The gas industry is well placed with probably just an additional training element to cover hydrogen gas, similar to what is currently done for LPG. Heat pumps will need a significant uplift in skilled workers, as the current level of skills availability is extremely low. I think it is a mistake to assume that gas installers will naturally migrate to heat pumps, and this remains a significant blockage to delivery at scale. There are also some skills gaps for the heat network industry, which are well known.

Above all though, affordability remains a key concern, especially for homeowners who may find themselves facing tough choices. If there is Government support for those less able to pay, there will always be a cut off somewhere, which will mean hardship for someone. Whoever you are and whatever size heating system you are looking after, having choice available to you as a consumer, is an important part of the picture. Without this, heat decarbonisation could struggle to gain traction, and this would have significant impact on our road to net zero.

For more information on how Bosch Commercial & Industrial can work with you to create the right heating system for your project, please visit our website.


Please note: This is a commercial profile

© 2019. This work is licensed under CC-BY-NC-ND.

Contributor Profile

Commercial Technical Operations Manager
Bosch Thermotechnology Ltd
Phone: +44 (0)1905 75 7536
Website: Visit Website


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