Decarbonizing heat in manufacturing — focus on renewables

Paul Murphy, of Climeaction, outlines how companies are making smarter energy choices that are good for the environment while also reducing their costs

The pathway to decarbonization of electrical energy sources in manufacturing is well understood. A shift from purchasing energy produced by fossil fuels, to renewable energy systems such as Wind and Solar, or through purchase of Guaranteed Certificates of Origin enables manufacturing companies to decarbonize their energy supply.

At a national level our policies have been focused on decarbonization of electricity for years with our revised Climate Action Plan 2021 increasing the targets to 80% renewable electricity by 2030. 

An ambitious target, that will require significant investment, regulatory and policy changes, particularly in our planning system and investment in our grid infrastructure, the likes of which hasn’t been seen since the rural electrification program in 1946, a scheme my own grandfather worked on. The scheme was lifechanging for the people of rural Ireland, and ultimately led to the creation of the developed nation we live in today.

Paul Murphy is a Director and Solutions Lead at Climeaction and recently appointed to the board of directors of the Renewable Gas Forum of Ireland.

Like those that went before us, we are now at a critical point in our energy story, a point where the decisions that are made, will not only impact us economically, but may result in irreversible damage to our planet and our societal systems as we know it. In such a critical point in our energy story, one would wonder why the focus has been almost exclusively on electrical decarbonization considering that 4,914 MTOe is consumed in heat, almost twice the quantity of energy used in electricity.

Within that energy consumed for heat in Ireland approximately 33% is consumed in Industry to manufacture our food, dairy and beverages, pharmaceuticals, and many other essential products we use in our daily lives. 

These sectors are reliant on that heat, without it many products simply couldn’t be produced. A common phrase you may hear used in the industry or from government is “Electrification of heat”. In residential energy – this relates primarily to displacing fossil fuels using heat pumps or other applicable technologies. A success in many cases, however an expensive solution due to the fabric upgrades required to be effective, and a limited uptake – 2,900 grant aided in existing buildings from 2018-20 and 26,900 installed in newly built homes according to the SEAI over the same period.

Technically speaking electrification of heat in residential energy, makes sense – the low temperature requirements, coupled with the social need to upgrade the fabric of our homes to ensure occupant comfort and reduce fuel poverty – why wouldn’t we do this? But already electrification of heat in homes is facing infrastructural challenges in the availability of sufficient capacity on the electrical network.

Climeaction has expertise in the development of feasibility assessments in Renewable Energy such as Anaerobic Digestion.

Now let’s take the example of industry – how do we decarbonize heat in this sector? We know there is challenges in domestic grid infrastructure – so what about industrial? 

I’ll take the example of a client of ours in the dairy sector. The client has a Maximum Import Capacity of Electricity of 7,000 kVA equivalent to the supply of 583 homes. Electrical energy on this site accounts for about 10 GWh of energy – the remainder is supplied by fossil fuels to a value of 50 GWh of energy. 

To electrify this manufacturing facility a grid capacity of 40,000 kVA would be required, to account for peaks in heat demands. To put that in perspective that is the same as 4 towns such as Dingle. While not impossible, it is highly unlikely that electrification of heat in industry is a valid technical pathway. 

So how do we do it? There is no one-size-fits-all pathway for manufacturing, each site's energy demands, how they use the energy and the ancillary challenges of infrastructure, energy resilience and company preferences make decarbonization of manufacturing heat a challenge. 

Timing is also a significant consideration – energy costs are variable. Two years ago heat pumps made financial sense in many cases for low-temperature heating demands as electricity prices were low enough relative to the costs of fuel, so when accounting for the Coefficient of Performance of heat-pumps, the technology still saved money. 

Since October last year, with rocketing electrical energy prices, we have yet to see a heat pump installation stack up financially. There are however solutions to decarbonization of manufacturing heat – but anyone who sells you easy decarbonization is not selling an optimum solution and these should be evaluated in detail financially. 

We have devised a pathway that could be evaluated for any manufacturing facility – the solutions however are a hybrid. Figure 1 below describes a pathway that should be evaluated for every manufacturing company.

Figure 1 illustrates the Climeaction pathway to net zero in manufacturing heat. The best pathway for each business is different; however, by following the above principles, a cost-effective and technically viable solution with a return on investment is possible.

Pathway to decarbonization for manufacturing heat

There are a few key take-outs from our pathway to decarbonization for manufacturing heat:

• There is no simple solution – each business pathway will be different, expert support is required to ensure a return on investment.
• Evaluation of high and low-temperature demands is necessary to determine the suitable technological pathways to decarbonization.
• Identification of energy conservation measures to eliminate the need for heat is an essential step in the process — this may include removal of heat use entirely for some processes — take Ozone sterilization vs Steam sterilization as an example.
• Identification of opportunities to recover heat will reduce energy demands considerably, while sometimes technically complex, in almost all cases there are solutions.
• Currently, heat pumps alone make no financial sense in many cases; however, inclusion of a behind-the-wire source of renewable energy such as solar or wind at a suitable scale reduces the site average unit rates and ensures a return on investment.
• Biomethane offers a technically valid solution to decarbonization of heat — although there has been significant progress made in the development of this solution in Ireland from a policy perspective it will take 3-5 years before it is commercially available to the market — however companies should act now to ensure this is built into their strategy.
• Hydrogen appears nowhere in our strategies — we do not see this as a commercially viable solution for decarbonization of manufacturing ahead of 2030. Anything after this is too late for most companies who have committed to Science-Based Targets.
• Electrical Steam Boilers to use excess renewable energy when available on the grid may in time make financial and technical sense; however, regulations will need to pick up pace to enable this. A fantastic project is being trialed in one of the county's largest energy users in this area.
• Biomass – while technically feasible as a solution, has a long return on investment in many cases and growing evidence and policy shifts away from combustion of wood products which are valuable for other purposes may over the next number of years see an industry shift away from this technology.
• Renewable Energy – there are two valid renewable energy enablers for decarbonization of manufacturing heat – Behind the wire Solar / Wind and Biogas (Biomethane or BioLPG). To ensure a return on investment these need to be considered as part of a strategic approach of reducing energy use first.

Climeaction develops strategic ways for companies to reduce their carbon footprint in their cooling systems from an electrical perspective and provide advice on integrated decarbonization solutions to recover heat from these systems to reduce fossil fuel usage.

Climeaction are experts in the decarbonization of business, their focus on the full scope of a business emissions reductions across all scopes has accelerated their growth since they were founded in May 2022. 

Climeaction, part of the Leading Edge Group, clients now include some of the country's largest manufacturing facilities in the Food & Dairy, Semiconductor, Automotive and Medical Devices sectors. The business is currently expanding into the North American market and recently announced the creation of 30 jobs in the next two years. 

To learn more visit www.climeaction.com