Carbon emissions from buildings, construction hit new high, sector off-track to decarbonise by 2050

Despite increase in energy efficiency investment and lower energy intensity, the building and construction sector’s energy consumption and carbon dioxide (CO2) emissions have rebounded from the COVID-19 pandemic to an all-time high, a new report finds.

Released at the latest round of climate talks in Egypt, COP27, the 2022 Global Status Report for Buildings and Construction finds that the sector accounted for over 34 per cent of energy demand and around 37 per cent of energy and process-related CO2 emissions in 2021.

The sector’s operational energy-related CO2 emissions reached ten gigatonnes of CO2 equivalent – five per cent over 2020 levels and two per cent over the pre-pandemic peak in 2019. In 2021, operational energy demand for heating, cooling, lighting and equipment in buildings increased by around four per cent, from 2020 and three per cent from 2019.

This, according to the report from the Global Alliance for Buildings and Construction (GlobalABC), means that the gap between the climate performance of the sector and the 2050 decarbonisation pathway is widening.

Decarbonising the buildings sector by 2050 is critical to delivering these cuts. To reduce overall emissions, the sector must improve building energy performance, decrease building materials’ carbon footprint, multiply policy commitments alongside action and increase investment in energy efficiency.

For instance, the sector’s emissions intensity in kilogrammes of CO2 per square metre dropped from 43 in 2015 to 40 in 2021 and energy intensity in kilowatts per hour per square metre slightly decreased, from 153 in 2015 to 152 in 2021, while investments in building energy efficiency have gone up by unprecedented levels, rising by 16 per cent in 2021, over 2020 levels, to $237 billion.

However, growth is outpacing efforts on energy efficiency and reducing energy intensity. The increase in global gross floor area between 2015 and 2021 is the equivalent to the total land area covered in buildings in Germany, France, Italy and Netherlands: if it were built on one level, at around 24,000 sq. km.

The report says that investments in energy efficiency must be sustained in the face of growing crises – such as the war in Ukraine and the ensuing energy crisis, and the cost-of-living crisis – to reduce energy demand, avoid CO2 emissions and dampen energy cost volatility.

The buildings sector represents 40 per cent of Europe’s energy demand, 80 per cent of it from fossil fuels. This makes the sector an area for immediate action, investment and policies to promote short and long-term energy security.

Also, critical to reducing the sector’s emissions is including buildings in climate pledges under the Paris Agreement – known as Nationally Determined Contributions (NDCs) – and mandatory building energy codes.

The number of NDCs that mention buildings grew from 88 in 2015 to 158 in 2021. However, progress on buildings and construction policies and action remains slow. Over the same period, the number of countries with building energy codes rose from 62 to 79. However, only 26 per cent of countries have mandatory building energy codes for the entire sector.

In Nigeria and other African countries, the raw resource used is predicted to double by 2060 – with steel, concrete and cement already major contributors to greenhouse gas emissions. Materials used in the construction of buildings already account for around nine per cent of overall energy-related CO2 emissions.

Embodied carbon in buildings – the emissions associated with materials and construction processes – needs to be tackled to avoid undermining energy-saving measures. However, the sector can reduce its impact by, for example, looking at alternative materials and decarbonising conventional materials such as cement.

The African population is expected to reach 2.4 billion people in 2050, and 80 per cent of this growth will occur in cities. An estimated 70 per cent of the African building stock expected for 2040 has yet to be built.

To avoid increasing emissions, while building the stock necessary to move people out of informal settlements, and to create buildings that are resilient to the impacts of climate change, the African sector should look at sustainable construction materials and design techniques, in which the continent is rich.

Africa is also rich in renewable energy sources, solar and wind, which nations can use to power their buildings sustainably. The report recommended for the building coalitions of national stakeholders to set targets and strategies towards a sustainable, zero-carbon and resilient buildings and construction sector through Buildings Roadmaps. Following the GlobalABC roadmaps process and model, more than 30 countries and territories have been developing roadmaps.

It also wants national and sub-national governments to establish mandatory building energy codes and set a pathway for their building codes and standards to achieve net zero as soon as possible.

“Years of warnings about the impacts of climate change have become a reality,” said Inger Andersen, Executive Director of the United Nations Environment Programme (UNEP). “If we do not rapidly cut emissions, in line with the Paris Agreement, we will be in deeper trouble.”

The report shows that the sector can still change. For example, rising fossil fuel costs, due to the war in Ukraine and the cost-of-living crisis, are providing incentives to invest in energy efficiency – although the erosion of purchasing power and the impact of labour and materials may slow investment.

“The solution may lie in governments directing relief towards low and zero-carbon building investment activities through financial and non-financial incentives,” continued Andersen.