On Wednesday, 30 September 2020 UNFCCC and the GlobalABC, in collaboration with the Cool Coalition organized the Technical Expert Meetings on Mitigation 2020: Cool Buildings For All
During the first session on cool buildings for all, we learned that cooling in buildings contributes greatly to global warming, and in a warming world, energy demand due to cooling is rising rapidly. Indeed, emissions from cooling could become as high as overall emissions from single countries, such as the US. In India, 70-80% of emissions will be due to space cooling by mid-century.
Addressing cooling demand requires a comprehensive approach in the form of avoid-shift-improve: Reducing the need for mechanical cooling in the first place is a critical first step and to achieve this, we need to make use of passive designs, both for new buildings and for retrofits, and take solutions to scale such as cool roofs, nature-based solutions at city and buildings level, and promote sustainable construction material that naturally controls humidity.
Passive designs for example can reduce energy demand from cooling by 50-70%. In addition to reducing energy demand, cooling strategies that include natural ventilation, filtration and fresh-air circulation also reduce health risks related to the spread of airborne illnesses.
Locally adapted and sustainable materials are part of the solution. For example certain types of agro waste can effectively reduce heat and absorb moisture. For this to work, local ecosystems and markets are needed, as well as a shift in perception as to which buildings materials are perceived as viable.
Nature-based solutions can be effective at cooling entire neighborhoods an cities, with added benefits to ecosystems and health and wellbeing. Urban canopy cover for instance reduce average ambient temperatures, increase livability and air quality for urban environments, and provide recreational spaces. Indeed, trees are some of the most viable options for natural cooling. To that end, the City of Melbourne has put in place a target of a 43% canopy cover, The City of Riyadh for instance has planned 3300 new parks and aims to green all major roads. For such solutions to work at scale, they need to be included in urban planning and design strategies.
Once mechanical cooling load is reduced, remaining cooling demand can be med by sustainable means such as district cooling systems powered by renewable energy. Super-efficient appliances are viable sustainable technologies to close the remaining cooling gaps.
Important enablers include buy-in from local and national governments, for instance through cooling/heat-reduction action plans and including cooling-related commitments into nationally-determined contributions.
In summary, there is an urgent need to rethink how we use and cool buildings around the world, but technical, policy and financial solutions already exist, ready to be implemented at scale. Solutions need to be tailored to local physical and social circumstances and supported by buy-in from and awareness raising and technical capacity building of national and subnational policy makers.
- Gabby Dreyfuss, Chief Science Advisor, Kigali Cooling Efficiency Program
- Jessica Grove-Smith, Senior Scientist, Passive House Institute
- Mae-ling Jovenes Lokko, Director, Building Sciences Program, Assistant Professor of Architecture, Rensselaer Polytechnic Institute, Founder, Willow Technologies
- Polash Mukerjee, Lead, Air Pollution & Climate Resiliance, NRDC India
- Yvonne Lynch, Urban Greening & Climate Resilience Strategist, Royal Commission for Riyadh City
- David Callow, (Acting) Director Parks and City Greening, Strategy, Planning and Climate Change, City of Melbourne
This was the first of three sessions of the Technical Expert Meetings on Mitigation (TEM-M 2020) event series on “Human settlements: sustainable low-emission housing and building solutions. Technologies and design for buildings, housing and construction”.
The second session will focus on ‘Building (back) better: Mobilising the value chain towards circular economy' - you can join via this link. The third one on ‘Pathways for moving to scale’. You can find additional information here.