Net Zero and the Built Environment: The Journey to Carbon Efficiency
Peter Sayce, Product and Commercial Development Officer at Bramble Energy says the industry must go further to make sure that any new infrastructure is built in the most efficient way possible, and existing stock is improved and repurposed where possible.
25% of total UK greenhouse gas emissions (buildings and infrastructure) can be attributed to the UK built environment, and that rises to 42% if surface transport is included within the sector. We have seen a decrease in carbon emissions from the sector over the last two decades, with the way in which we construct buildings improving and the ‘green’ mindset becoming a major consideration when firms approach projects. However, the industry must go further to make sure that any new infrastructure is built in the most efficient way possible, and existing stock is improved and repurposed where possible.
As the goal of net zero by 2050 approaches, the built industry has a long way to go in order to achieve complete carbon efficient buildings. With so many processes that emit carbon to consider like powering sites, materials production, the embodied carbon of a build, along with the demand for infrastructure and building stock only set to grow as our population does, just how can the build sector implement long-lasting change now?
The net zero of our future
We are already seeing great examples of how net zero can be a possibility for the construction of new spaces, but how close are we to achieving more carbon efficient buildings? The truth is we need to see more. In London, Landsec has constructed and will operate The Forge, the UK’s first net zero carbon commercial development, in line with the UK Green Building Council’s framework. The building uses no energy from fossil fuels, and has focused on the use of recycled materials, with 18% less primary steelwork and 13% less concrete. In addition, 100% of the building’s waste is diverted from landfill. This shows the sheer number of processes involved, and also the wide range of thinking that must go into ensuring buildings are net zero by design.
It is now about thinking in a circular economy manner as the impact buildings have on our planet does not end when the construction phase is over, and the site opens its doors. Here are some solutions the building industry can consider in order to help take stepping stones to achieve net zero.
Using greener alternative solutions for energy on site
One of the main areas in which change will make a difference is how we power the sites we are building on. Currently, most sites are powered by diesel-fuelled generators which are used for everything from plant machinery to lighting – even the site kettle.
Red diesel has long been the go-to for the construction sector for off-road vehicles and machinery, having been backed heavily by government incentives. Users have been entitled to a rebate on the tax or duty paid on the fuel purchased. However, the government announced in the 2020 Budget from April 1, 2022, this entitlement was to be removed from most sectors, including construction.
Those with ambitious net zero targets will drive the sector. But the tech providers have to be offering solutions that are ultimately right, meaning the tech sector needs to deliver products that are authentic, affordable, and agile – providing a user experience that is comparable to existing equipment, if not superior.
Electrified or hydrogen-powered plants are becoming a progressively viable alternative to diesel-powered equipment, alongside battery, solar, and hydrogen generators which are also becoming increasingly available. Hydrogen fuel cells are a more sustainable solution for sites – powering rapid recharging points and providing long-lasting power for essential systems. However, a serious problem highlighted in a survey of 579 senior decision makers in UK construction, in November 2021 showed that almost a quarter (22%) of UK construction professionals said knowledge of how and where hydrogen can be used on site is a major barrier to adopting it as an energy source.
Developing and shaping the conversation around the use of hydrogen as to its safety and extensive applicability will be vital in the scaling and uptake of its widespread use.
A different approach to design and materials is necessary
Given that much of the future performance of a building is dictated by early decisions, achieving net zero carbon, both in operation and in construction, will mean changing the way that we approach design and construction. We will need to explore designs that use fewer materials, and then choose materials with lower embodied carbon. Simple choices such as using recycled steel rather than virgin steel and incorporating recycled concrete where possible can have a huge impact on the embodied carbon of the building.
Another design factor should be how the use of alternative energy sources to power a building’s life span can be incorporated such as fitting solar panels or introducing heat pumps and certainly for large residential construction, there should be a consideration for how these alternative fuels could be implemented to work for the whole community which would allow for the whole area to function off a completely renewable energy system.
There needs to be an input of standards and policy, where construction bodies and the wider government can help to carve out a new “go-to” industry standard for the use and production of construction materials. The production of concrete and steel are two of the biggest carbon emitters and some of the most difficult to decarbonise. That is not to say it cannot be done, but there is a long way to go before these green materials will be widely available. That is why it is important for engineers to focus on the repurposing and reuse of materials, especially at the end of life, and develop more of a “circular economy” mindset.
The built industry’s processes must change from the top all the way down in order for the sector to completely decarbonise its operations. More advanced construction techniques are already reducing waste and energy use, plus tackling other inefficiencies on building sites. Improved on-site maintenance, lean practices, waste reduction, and landfill avoidance are all fundamental to transforming the sector and the way in which we construct the built landscape.
Education, investment and adaptation
Truly sustainable construction will only be achieved with collaboration across the whole sector. There is still learning to be done as processes and technologies develop. The monitoring of buildings that have been constructed in different ways and how they fare over the decades will offer great insights into the future of green construction. The government also has a huge role to play in securing the future of the industry. Companies can – and should – access the support they're entitled to, in order to shift to more sustainable alternatives.
There’s work still to do…
It is encouraging to see the developments in the built sector but these need to be happening on a much larger scale. The built sector needs to prioritise and look at the bigger picture, but this is where Government grants are crucial. They may have set the targets, but without offering the right access, the right investment, and the right funding, there will be no way that adaptation and change can happen at the right pace and scale to ensure that 2050 becomes a reality.
The use of clean solutions across the built sector is realistically still small scale which means costs remain high. However, without the Government driving awareness and making support easily accessible across the board, the reality is most of the sector will not be able to implement these crucial solutions as their “go-to” standards moving forward.
