Le refroidissement des bâtiments au cœur des politiques d’économie d’énergie (en anglais)

Le récent rapport “Energy Efficiency 2018 de l’AIE souligne que le conditionnement d’air est le poste où l’utilisation finale d’énergie progresse le plus dans les bâtiments et appelle à intensifier les gains en termes d’efficacité, notamment par le renforcement des normes de performance énergétique minimale.

According to the recent International Energy Agency (IEA) “Energy Efficiency 2018” report, global energy demand rose by 1.9% in 2017 – the fastest annual increase since 2010. The forces driving energy demand, led by strong economic growth, outpaced progress on energy efficiency. However, without energy efficiency progress, increased economic activity would have had a greater impact on the global energy system. Efficiency improvements made since 2000 prevented 12% additional energy use in 2017.

There is still huge potential for energy efficiency gains, IEA claims. Since 2000, primary energy demand has grown by 39% and the global economy has grown by nearly 85%. In the IEA “Efficient World Scenario” (EWS), which assumes the adoption of all cost-effective energy efficiency opportunities between now and 2040, the global economy doubles but there would be only a marginal increase in primary energy demand.

In 2017, buildings and appliances were responsible for around 30% - representing 120 exajoule (EJ) - of global final energy use. Energy savings of 14 EJ have been achieved since 2000, thanks to expanded energy efficiency policy coverage, technology improvements and investment trends. Despite these impressive savings, considerable potential for cost-effective energy efficiency was not achieved between 2000 and 2017. For example, if the least efficient refrigerators in the world (around 30% of the stock) had been subject to minimum standards and reached the efficiency of the global average (a 30% reduction in energy consumption), around 170 petajoule (PJ) of energy would have been saved in 2017.

The EWS highlights the potential for global building energy demand to remain flat between now and 2040, despite total building floor area growing by 60%. Buildings in 2040 could be nearly 40% more energy efficient than today. Cooling energy use in buildings has more than doubled since 2000, from 3.6 EJ to 7 EJ, making it the fastest growing end-use in buildings, led by a combination of warmer temperatures and increased activity due to population and economic growth. Without efficiency gains, space cooling energy use would more than double between now and 2040 due to increased activity and use of air conditioning. In the EWS, energy efficiency for cooling offsets much of the climate, activity and structure impacts to limit cooling energy growth between now and 2040 to 19%.

IEA stresses that space cooling is a major driver of building energy demand and will require policy attention to realise efficiency gains.

Globally, 34% of building energy consumption was covered by mandatory energy efficiency policies (e.g. codes and standards) in 2017. At the end-use level, lighting and cooling are leading the way with mandatory policy coverage around 80%. Recent increases in coverage in space cooling have come from countries such as Jordan and Peru that introduced new standards and labelling programmes effective in 2017.

Refrigeration and space cooling have shown the largest policy progress, through a combination of growing policy coverage and increasing strength in some countries. The European Union, India and the United States regularly revise performance requirements for products, which continuously improve the strength of these policies.

However, while most of the countries that have high penetration of air conditioning do have mandatory energy efficiency policies for cooling equipment, some hot countries still lack these key policies and cooling equipment policy strength has only incrementally improved in 25 years.

In particular, there is significant scope to raise minimum energy performance standards. While the efficiency of best available air conditioning technology has continued to improve, there is significant potential to close the gap between the best available technology and the market average. In the EWS, average air conditioner efficiency could double, which is possible with current technology. Global best available air conditioning equipment is up to five times more energy-efficient than the least efficient equipment currently available, based on the seasonal energy efficiency ratio (SEER), which reflects the average annual energy efficiency of cooling equipment.

Finally, IEA stresses that public support for cooling-related research is needed to ensure the development and deployment of energy-efficient air conditioning equipment, as well as efficient building solutions.

International Energy Agency, Energy Efficiency 2018 - Analysis and Outlooks to 2040: https://www.iea.org/efficiency2018/