Megacities such as London are currently the source of 52% of the world’s greenhouse gas (GHG) emissions. As of 2020, 83.9% of the population lives in such places, resulting in increasing pressure for a more sustainable use of space and energy within such communities.
When considering the impact of the built environment on GHG emissions and climate change, the entire lifecycle of a building must be considered. This includes its construction, operation and demolition.
It is impossible to quantify such an impact, as well as to make a comparison or an informed decision, without data. Data is the foundation of any improvement. To be effective, data must conform to common formats, standards and defined protocols to ensure it is collected in a consistent and interchangeable manner.
Such protocols and the associated creation of common data formats and standards to report, for instance, on a building’s energy usage. Doing so will enable technologies, such as digital twins, to be used to optimise both building operation and design in support of reduced GHG emissions.
Further, the exchange of data on building occupancy and environmental conditions will optimise the utilisation of buildings, as well as indoor and outdoor spaces. Non-residential building spaces, such as schools and office buildings, are frequently underutilised.
This policy paper focuses on the UK, where, in 2019, residential and business sectors represented a proportion of some 32% of total emissions. By focussing here on energy use according to sector, it is believed that access to appropriately-structured and -configured information based on robust, validated data will enable a significant reduction in building energy use in the short, medium and long terms.
DATA IS THE BASIS
In the short term, data has the potential to be used to report on energy consumption and GHG emissions and, in doing so, provide further knowledge on the operational characteristics within buildings contributing to GHG emissions per sector. For example, data could be used to demonstrate variations in GHG emissions between providers of social housing, such as local housing authorities and housing associations. This would enable local authorities and others to understand their performance in relation to other similar bodies and organisations.
However, the data needed to drive this process of innovation must be derived and shared in a manner that is understood by key stakeholders, is transparent and is consistent. Through openly exchanging information on measures for energy efficiency, such as operational carbon and embodied carbon, such stakeholders as homebuilders can share best practices and develop consistent methods to drive the built environment towards more efficient and dynamic energy systems.
Embodied carbon or embedded emissions represent all the GHG emissions associated with the construction of a building, including those from the extraction of raw material, the subsequent production of building materials and the manufacturing of the finished product and machinery use. There is increasing demand to collect and measure levels of embodied carbon and hence the GHGs emitted before the building is in operation, which in most cases accounts for the bulk of the GHG production, perhaps as high as 75%, associated with a building over its lifetime.
According to the Chartered Institution of Building Services Engineers (CIBSE), it is imperative that a consistent approach is used to gather data from manufacturers, as well as to calculate and report on the embodied carbon of individual buildings, to calculate the embodied carbon of products associated with the mechanical, electrical and public health (MEP) systems within buildings.Similarly, the adoption of technologies used to manage and control energy systems when buildings are in operation has been affected by a lack of consistency in the data. Embodied carbon is extremely complex to quantify and measure when compared to operational carbon. Although a variety of technologies and systems exist to empower UK property developers and housebuilders to calculate and manage their embodied carbon, such as the construction carbon scoring tool developed by UKGBC, a consistent approach is still needed.
A short-to-medium-term goal should therefore be to work with building operators to generate more robust data standards, along with the associated protocols for analysis and interpretation of the data to enable the collection, analysis and reporting of operational GHG emissions across all sectors.
The Institution of Mechanical Engineers recommends establishing the regular publication of the requisite data to support effective decision making. This would involve building owners and operators sharing data on energy usage from building operations, in a similar manner to the Royal Institute of Chartered Surveyors’ (RICS) Building Carbon database.
Such data then constitutes a collaborative tool that can be used to generate a common set of requirements or data sets for measuring energy emissions from building operations concerning such operating parameters as heating, lighting, occupancy and ventilation. In doing so, the data gathered can be used for knowledge transfer and benchmarking.
Possible data types to be recorded could include:
Energy consumption (by floor, room, type of space, etc.) to support performance assessmentOccupancy levelsThe nature of the utilisation of building spaces.Other operational parameters to be measured and recorded could include:
Lighting and illumination (both natural and artificial)Ventilation and air conditioning (including pollutants)Weather conditions, such as air temperature and wind.SUMMARY
In achieving the Net Zero goal, the built environment presents a complex problem with no easy solutions. It is also an environment in which there is a need to balance incentives and penalties while encouraging organisations that can create best practices and assisting property owners and occupants in the best use of technologies, both current and future. This not an easy balance to achieve, and it requires the removal of often artificial boundaries between sectors to find solutions.
Finally, it must also be recognised that ultimately, the solutions to achieving Net Zero are not likely solely technological, and there is a need to balance developments in and applications of technology with wider educational approaches aimed at achieving necessary societal changes.