Urban Buildings Need Clean Heating and Cooling 

Cities are wasting heat, but smarter networks and heat pumps can create clean, circular urban energy systems. 

This opinion editorial is produced in co-operation with the European Sustainable Energy Week 2025. See ec.europa.eu/eusew for open calls. 

Efficient heating and cooling are essential, yet much thermal energy goes to waste. What if we could avoid this thermal pollution and establish a circular energy economy in urban areas by recovering and recycling waste heat? Thermal networks as heat collectors and transport means, heat pumps as energy lifts, storage and clean renewable energy sources can turn this dream into reality today. 

As the climate crisis worsens and urban populations grow, cities face increasing pressure to improve infrastructure and services. Cities need to be more resilient against extreme weather incidents and heat waves. The use of fossil energy must be replaced by clean alternatives. This is not only a response to climate change, but an obligation codified in EU law, notably the EU Energy Performance of Buildings and the Renewable Energy Directives.   

The symbiosis of heat pumps, low-temperature energy grids, and the use of renewable electricity/heat provides a solution.  

Unlocking “the energy chest” of cities   

Traditional district heating and cooling distribute high-temperature thermal energy generated in central plants to their clients. Even using insulated pipes, some energy is lost in the distribution. Changing from central to decentralised networks and reducing operating temperature avoids this disadvantage. Low temperature, multi-input-output networks connect all types of buildings requiring heating and cooling. They collect waste heat from many different sources (such as industrial processes, offices, data centres, and public infrastructure) and distribute it where needed.  Heat pumps raise the temperature to the required level at the point of demand.    

Heat pumps for clean thermal energy  

Heat pumps extract heat from a source (air, water, ground, or a thermal network), lifting it to a higher temperature level to provide heating. At the same time, the source is slightly cooled. Heat pumps always provide useful heating and cooling, and it depends on the system design which of these services can be used.   

Heat pumps extract heat from a source (air, water, ground, or a thermal network), lifting it to a higher temperature level to provide heating.

Connecting the many energy users and (waste) heat providers in a city through a thermal network and adding heat pumps of different types and capacities in apartments and buildings (see circles) enables the collection of waste heat and the highest heating and cooling efficiency. One user’s waste heat becomes another user’s heat source (see figure 1).  

Multiple benefits for cities  

The benefits of cities transforming their heating and cooling infrastructure are plentiful.  

• Replacing fossil fuels with clean energy reduces carbon dioxide emissions and air pollution, which leads to better air quality.   

• Collecting waste heat from cooling limits the heat island effect in cities. Buildings equipped with cooling help citizens withstand heat waves. Cities and citizens are more resilient to already observable climate change.   

• Storage tanks and the energy grid operate as a thermal battery, balancing the electric grid.   

• Local energy sources, used by European technology solutions and designed and installed by a European workforce, help Europe become largely independent of fossil energy.    

Collecting waste heat from cooling limits the heat island effect in cities. Buildings equipped with cooling help citizens withstand heat waves.

Breaking barriers to adoption  

Implementing heat pump technology and thermal networks faces challenges. Upfront investment costs, regulatory hurdles, and limited public awareness can slow progress. Cities and policy-makers should incentivise modern heat pump-based heating and cooling by making deployment easy and economically attractive. Cities should make thermal networks part of their public waste heat collection infrastructure.   

Convincing humans is also key. Campaigns explaining policy, highlighting the benefits of clean heating and cooling and explaining how end users will be supported in their decision-making will create trust and accelerate adoption by decision-makers.   

A path to sustainable cities  

Urban heating can become decarbonised, efficient and sustainable while creating cleaner, more affordable, and resilient communities.

Urban heating can become decarbonised, efficient and sustainable while creating cleaner, more affordable, and resilient communities. The technology exists; its potential is enormous. Let’s make use of it. Clean heating and cooling are not just a choice – they are the cornerstone of Europe’s energy and climate policy.  

Disclaimer: This article is a contribution from a partner. All rights reserved.