The following article, written by award-winning freelance journalist Tim Smedley, originally featured in the Raconteur Insight ‘How tech is cutting energy waste and boosting efficiency in manufacturing.’ You can access the full report here.
The clock is ticking for the built environment to reduce its carbon emissions, particularly in manufacturing, where energy wastage means overall efficiency is compromised and net-zero targets are under threat.
In fact, some 70% of carbon emissions worldwide can be linked to infrastructure, of which the built environment contributes around 38%.
In the UK, infrastructure is responsible for more than half of the UK’s total carbon emissions. The recent House of Commons Committee report into carbon in construction makes the case for urgency: “Emissions from the built environment must be reduced if the UK is to meet net zero by 2050… pressingly, the UK’s Sixth Carbon Budget requires carbon emissions to be reduced by 78% by 2035, compared to 1990 levels”.
This pathway for Carbon Budgets has been in place since the Climate Change Act of 2008 – and the science has been clear for far longer, with the IPCC first reporting in 1990. So why are the emissions of the manufacturing, construction and built environment sectors, still so high?
Jim Hall, trustee for carbon and climate for the Institution of Civil Engineers (ICE), believes that there is “no one reason” but ascribes it in part to the fact that “much of our infrastructure is old, and was built in times when considerations around net zero weren’t there. But we have also been slow to innovate and adopt new ways of working…. carbon is woven into almost every aspect of infrastructure currently. But, that doesn’t mean we can’t, and won’t, find new ways of approaching things.”
The Climate Change Committee’s (CCC) 2022 progress report to Parliament told of “lagging behind” with “signs that delivery timelines are starting to slip” in the manufacturing and construction sectors. Hall describes the CCC report as “a stark warning”, and highlights the potential for greener solutions including retrofit, reuse, and ‘build nothing’ options, plus removing fossil fuel consuming products from all new and retrofitted projects.
Nature-based solutions and green infrastructure need to be brought to the fore, too. “On an industry level, we need to be thinking about the materials we use”, says Hall. “The manufacture of cement and steel are both highly energy intensive. We need to find alternatives which are equally robust and available”.
Cement alternatives include alkali-activated cementitious materials (AACMs), made from a mix of source alkali (calcium oxide) and aluminate-rich industrial by-products such as blast-furnace slag and fly ash – this was used in a recent upgrade to Chatham train station in Kent, achieving 83% CO2 savings compared with traditional concrete. Another alternative is hempcrete, made from 30% lime and 70% hemp crop, and believed to be carbon negative due to the carbon absorbed by hemp as it grows. An M&S 42,000m² superstore in Cheshire Oaks is clad with hempcrete panels.
Green building codes
New building codes and standards play an important role, too. PAS 2080 for example is a UK-made but globally-applicable standard for managing carbon in building and infrastructure. HS2 engineers achieved a 27% reduction in structural steel use for Old Oak Common station, equating to 2,700 tonnes of carbon and a cost saving of £7m, by following the standard.
Anglian Water also achieved a company-wide 61% reduction in capital carbon and a 22% reduction in capital expenditure with PAS 2080 certification. While other industry initiatives such as the new Built Environment Carbon Database (BECD) set out the actions needed to get to a net zero future, with benchmarks and case studies.
Internationally, however, Victoria Burrows, director, Advancing Net Zero, at the World Green Building Council (WGBC), explains that “many building codes do not reflect the level of ambition required to deliver high performance buildings, and one of the biggest challenges is the renovation of existing buildings to meet today's standards. So, as we continue to build, unless we drastically increase renovation rates, we are further contributing to the problem.”
She adds that “the average timeframe of bringing a new project to market can be several years, so it would be a long time before we see improvements reflected in the sector's emissions. This is why we need to act now, to ensure that every project being designed today is optimised for performance and whole-life carbon.”
Choose lower-carbon materials
The WGBC recently released its Global Policy Principles for a Sustainable Built Environment which outline the key policy levers that could help reach the goals of the Paris Agreement, including minimising the use of primary materials by promoting circular economies, and avoiding development on land with high biodiversity. In particular, Burrows calls for “innovations in building materials, technologies and design approaches that make it easier to choose lower carbon options, and ultimately reduce how much energy we consume – and waste – in our buildings.
“At a building level, this could include electrification, buildings as prosumers – producing more energy on-site than they consume – and deep renovations. At a district or city scale, this could require transition from gas networks and other fossil fuel sources, district heat capture, community grids and resource sharing”.
A report published by global engineering company Danfoss estimated that in the EU alone, excess heat lost from buildings and manufacturing was equal to 2,860 TWh a year, almost equal to the EU’s total energy demand for heat and hot water. When you zoom in to individual urban areas, the potential becomes even clearer. Essen, in Germany, hosts approximately 50 industrial sites that collectively produce 11.98 TWh of excess heat per year. This is roughly the amount of heat required to heat 1.2m households.
In Europe, where heating is largely generated by burning fossil fuels and accounts for over 50% of annual energy consumption, reusing such excess heat could be transformative. This can be done within buildings by using heat recovery units, or across urban areas via district heating networks that combine heat from multiple sources and distribute it through pipelines to end users.
Unearthing operational energy savings
In Ireland for example, Amazon Web Services has linked its data centres to a district heating scheme in Tallaght, South Dublin, which will provide heat for 47,000 m2 of public sector buildings, 3,000 m2 of commercial space and 135 affordable rental apartments. The UK meanwhile is home to over 450 data centres, all producing excess heat which is – currently – largely going to waste.
At a corporate level, organisations need to better understand their energy use before they can begin to adequately reduce it. “Carry out energy audits of your existing facilities”, advises Burrows, “install Building Management Systems (BMS) and conduct Whole Life Carbon Assessments (WLCA) on all new development projects.
This data can allow you to make informed decisions about where you can make energy efficiency and carbon savings — from LED lighting, to HVAC upgrades, access to renewable energy, and low carbon material choices.” More detailed advice is available from the local Green Building Council network, tailored to each specific market.
“Changing the way we do things will take time”, admits Hall at ICE, “so we need to give careful consideration of the types of projects which are approved, taking into account the impact they might have down the road.” He offers an example that takes ‘down the road’ literally. “In Ireland, we are seeing the government significantly shift some of its investments from road projects to public transport projects such, as metro or bus routes”.
Such decisions, that take an existing budget and re-prioritise it – or an existing asset and repurpose it – for lower-carbon alternatives, can both impact carbon emissions immediately, and for decades to come.