Infiltration of cold air can also cause mould and lead to material degradation, which affects the health of occupants and the lifetime of the building.

Proper control of air flows and ventilation is even more important in hot climates to keep buildings healthy and comfortable. Enhanced building designs can allow natural ventilation and maintain comfortable temperatures without mechanical assistance. Ventilation systems can also help keep buildings healthy by removing indoor air pollutants and controlling the thermal environment.

Integrated storage and renewable energy technologies for buildings

Integrated storage and renewable energy technologies for buildings (e.g. pairing clean energy production with local storage and energy use) can address multiple climate change mitigation objectives at once. One such solution is thermal energy storage, which can displace cooling and heating demand while also enabling higher penetration of variable renewable sources in the energy system. Integrated renewables (e.g. on a building's facade) can also enable greater energy production, as the related area usually is much larger than rooftop space.

Heat pumps

Heat pumping technologies for space heating already exist and will deliver significant efficiency improvements and considerable CO2 emissions reductions in many countries.

Innovation could help to address some known market issues, including high upfront prices and a lack of adaptability to multiple building contexts (e.g. multi-family residential buildings with limited outdoor space for exterior heat pump units). While packaging products can increase marketability, multiple synergies with other energy technologies such as solar PV and district heating networks could also be exploited to enhance system flexibility and efficiency.

Raise heat pump attractiveness

Increasing heat pump attractiveness would buttress the clean energy transition, ensuring good heating equipment efficiency that can be employed affordably in different building applications and with other clean energy technologies such as solar PV and energy storage. Further R&D investments would address many barriers to heat pump deployment by making them more compact, easier to install, more efficient, less carbon-intensive and more flexible than conventional heat pumps through enhanced interactions with the grid.

Enhance heat pump flexibility

Greater electrification of heat (and other end uses such as space cooling) will place greater pressure on electricity systems, requiring not only improved energy efficiency but also greater flexibility through demand-side response. Markets with high shares of electric heating (e.g. France) illustrate the impact of electric heat demand during the winter and on extremely cold days. Heat pumps with high energy performance factors can help reduce the overall tendency of demand peaks, but flexibility through demand side response will still be required to shift some demand to off-peak hours.

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