Conventional refrigeration equipment (e.g. refrigerators, room air conditioners, industrial chillers) already accounts for 10 % of greenhouse gas emissions worldwide. This is more than twice the emissions from all air and sea transport. As a result of global warming and associated extreme weather events such as heat waves, combined with the increase in the world's population and growing urbanisation, emissions from cooling could double by 2030 and triple by 2100 if conventional cooling continues.

There is a risk of mutually dependent or reinforcing effects: Cooling exacerbates global warming by essentially still relying on fossil-based energy, causing additional carbon dioxide (CO₂) emissions. In addition, depending on the cooling technology, refrigerants such as fluorinated greenhouse gases (F-gases) can escape from cooling systems with a climate impact 100 to 24,000 times greater than that of CO₂. At the same time, worsening global warming is in turn driving demand for cooling, increasingly in private households as well. Progressive global warming and the associated accumulation of heat extremes and hot spells already pose risks to physical well-being and health, and these risks are set to increase. Most affected are the elderly, the chronically ill, pregnant women and young children. Currently, about 1 billion people in the 54 countries most affected by heat live in poverty and with little or no access to cooling. A recent study concludes that, depending on actual global warming and population growth, between 1 and 3 billion people will be living in areas with an average annual temperature of over 29°C.

The fact that the consequences of global warming are already being felt in Germany is shown by the Federal Government's second monitoring report on climate impact adaptation. Since climate records began in 1881, the mean air temperature in this country has increased by 1.5 °C by 2018. This value exceeds the mean global temperature increase over the same period by 0.5 °C. In Germany, the increase in mean annual temperature was accompanied by a significant increase in heat days with a maximum temperature of at least 30 °C.

The following main options for action can be considered for more sustainable, climate-compatible cooling:

• the use of efficient and low-emission cooling technologies,
• enabling access to these technologies for broad sections of the population, and
• avoiding excessive heating of buildings and inner cities.

Not only technological innovations can contribute to sustainable cooling worldwide, but also innovative approaches, e.g. in the fields of urban and spatial planning and services.

Objectives and approach

This brief study aims to provide an overview of such technological and social innovations as well as service innovations and novel business models that focus on developing efficient and low-emission cooling technologies and concepts as well as enabling access to these technologies for broad sections of the population.

Using the examples of selected cooling technologies for service and social innovations (such as the CaaS model - Cooling as a Service) as well as cooling strategies and concepts (e.g. from urban and spatial planning), advantages and disadvantages, possible diffusion barriers, costs and benefits as well as necessary prerequisites for implementation - including political, social, possibly cultural framework conditions and governance aspects - will be presented comparatively.

Due to the considerable societal, economic and political relevance on a national as well as on a global level, the brief study will consider application possibilities and preconditions in Germany as well as in developing countries. Another aspect of analysis is the consideration of the German and European innovation and business landscape, its market position and its potential to contribute to sustainable cooling in Germany and worldwide, e.g. with technologies, service innovations or novel strategies and concepts.

Project progress

The starting point is the topic profile Sustainable Cooling - nachhaltige Kühlung bei Hitze (PDF), developed  as part of the 2020 Horizon Scanning. The short study prepared by TAB is currently in the process of being approved by the TA rapporteur group.