Minimising energy in construction

The built environment is estimated to account for around 50% of all carbon emissions. About 10% of global GDP is generated by the construction industry, which creates and maintains our built environment. Recent success in reducing operational energy consumption and the introduction of strict targets for near-zero energy buildings mean that the embodied energy will soon approach 100% of total energy consumption.

The importance of this fundamental shift in focus is highlighted by the analysis of recently constructed steel and concrete buildings, in which it was demonstrated that embodied energy wastage in the order of 50% is common. Inefficient over-design of buildings and infrastructure must be tackled to minimise embodied energy demand and to meet future energy efficiency targets.

The UK Government has set out its ambition to achieve 50% lower emissions, 33% lower costs, and 50% faster delivery in construction by 2025. These ambitious targets must be met at the same time as the global construction market is expected to grow in value by over 70%. Achieving growth and minimising embodied energy will require a step change in procurement, design and construction that puts embodied energy at the centre of a holistic whole-life cycle design process.

The global population is expected to grow to 9.7billion by 2050, with 67% of us living in cities. China alone will add 350 million people to its urban population by 2030. Yet Europe's and Japan's population will both be smaller in 2060 than they are today, and the total population of China is expected to fall by 400million between 2030 and 2100. Depopulation of cities will occur alongside reductions in total populations for some countries. This presents a complex problem for the design of the built environment in which buildings and infrastructure constructed today are expected to be in use for 60-120 years: providing structures that are resilient, healthy, and productive in the medium term, but demountable and potentially reusable in the long term. The targeted feasibility studies of this proposal will be vital in ensuring that this can be achieved.

We have identified a series of areas where feasibility studies are essential to define research needs to enable significant energy savings in the construction industry before 2025. We will identify a series of 'low-hanging fruit' research areas, in priority order, for embodied energy savings, and work with our industrial partners to develop feasible pathways to implementation in the construction industry.

There are four key objectives to this proposal: 1) establishing the feasibility of upper limits to the effect-resistance gap; 2) understanding how geometry and structural behaviour can be exploited to save embodied energy; 3) understanding feasible construction protocols to enable this fundamental change; and 4) evaluation of the unintended consequences of each study. Each of these objectives is expected to have a range of non-academic impacts, falling into the themes of Knowledge, Economy, Society and People.

The knowledge arising from each of the Work Packages will have benefits and applications for architects, building contractors and structural engineers as it is aimed squarely at changing the culture of design. The outputs of WP1 will be directly relevant to the thousands of engineers across Europe and the world who use the Eurocodes as their basis for design. University of Bath visiting Professor Denton, in his role as chair of the European Committee CEN TC250 (the overarching committee for all Eurocodes), will be able to assist in providing the forum needed to make this impact a reality. The outcomes of this proposal will ultimately feed into and inform industry standard design tools.

The industry will benefit economically from reduced material consumption, more sustainable structures, and a culture that puts whole life energy as a key design stage gate. Future revisions to design codes and possibly legislation to mandate material efficiency would benefit the sector, establishing an imperative for excellence in initial design that puts long term performance as a key driver. This will create new business opportunities for the sector to expand to provide this capability.

This proposal has significant future impact for the public. Whilst they may not notice day to day changes in building design processes, the reductions in material use will benefit them through reduced energy, emissions, and material consumption. Minimising material waste, and establishing methods for a circular economy will support the UK as a productive nation. New tools which to link the design, operation, deconstruction, and reuse resulting from this proposal will support our connected nation. Our proposal is influenced by funded research in other areas that is considering how building design can create a healthy nation. By establishing the consideration of whole life cycle performance as a key part of sustainable design, the feasibility studies of this proposal support a resilient nation.

This proposal will identify key areas to target in future research. As such it represents the first step in the training of engineers, and students, in the new design protocols required. PDRA1, employed on this project, will be the first of these. We will embed our findings in the Centre for Doctoral Training at Bath (dCarb). In addition, we will target all levels of personnel in our industrial partner companies through the newly established user engagement groups such that they begin to use our proposals and design guides in their everyday design work.

A roadshow to 14 UK cities and exhibition in London, supported by our partners and the network of the Institution of Structural Engineers, will target industry, students, and interested members of the public in a series of workshops and seminar presentations by Dr Orr. This will build on the new 'User Engagement Groups' established through our impact plan and grown organically through our online portal.

This proposal will impact national and international policy makers. Enabling amendments to design codes that encourages optimisation (by specifying minimum AND maximum performance requirements) is crucial. Dr Orr will work with the University of Bath Institute for Policy Research and the IStructE on the preparation of briefing papers for the Department for Business, Energy & Industrial Strategy and the Department of Communities and Local Government.