Redesigning Cooling for a Warming World

Engineers are rethinking HVAC design to deliver sustainable, low-carbon cooling for a rapidly warming world, says Stephen Kofi Duah Appau, Chief Executive Officer, Ideal Air Services Ghana Limited.

UN chief António Guterres recently acknowledged that the 2015 Paris Agreement aim to limit global warming to 1.5°C will be overshot, and according to the UK’s Climate Change Committee, existing buildings and infrastructure should be upgraded to withstand temperatures of at least 2°C higher than normal by 2050.

As it stands, air conditioning is responsible for three per cent of carbon emissions and seven per cent of global electricity usage, with demand expected to triple by 2050. Innovation in this industry has never been more important.

Effective futureproofing against the impacts of climate change puts the need for sustainable cooling at the center of retrofits and refurbishments to minimize stranded assets in the UK. According to research by Knight Frank, up to £700bn worth of UK commercial property is at risk of depreciating in value because of poor energy performance as new regulations come in.

This National Engineering Day, it’s important we spotlight how modern engineers are tackling one of the built environment’s biggest challenges:

cooling in a warming world. In adopting a solutions-driven and design led approach, engineers have the opportunity to transform how heating, ventilation, and air conditioning (HVAC) systems perform, look and feel.

Rethinking HVAC to reduce carbon

Since the introduction of electronically commutated (EC) motors for fan coil units (FCUs) 20 years ago, the HVAC industry has gone largely unchanged. But a recent return to the HVAC ‘drawing board’ and the first principles of physics has led to exciting innovations that are now evolving the air conditioning industry.

New solutions being developed by engineers are more compact and elegant, delivering better comfort with fewer materials and using significantly less refrigerants. These solutions come together to create higher-performing, water-based systems, utilizing physically smaller units that are quicker to install and easier to maintain.

Reducing the number and size of components used in the HVAC systems, as well as choosing materials with low embodied carbon, reduces the overall embodied carbon of the building.

Better design, system integration and technical innovations, enable lower fan power and the ability to operate at higher chiller performance coefficients. This reduces the energy required for heating and cooling and creates significant operational carbon savings.

Simplicity through design excellence

This new generation of HVAC units is also changing the game when it comes to design simplicity and reuse. Compact, highly modular units with multiple components in one box make it technically very easy to integrate into a ceiling, reducing the need for ducts and diffusers and maximizing floor-to-ceiling heights. These prefabricated solutions bring the added benefit of radically simplifying the design stage for MEP consultants.

Compared to many existing systems, they also lend themselves to removal, repositioning and re-installation. In some cases, units can even be removed from one building and installed in another - further reducing cost and carbon and supporting a circular economy.

Transforming user experience with enhanced comfort

Alongside carbon and design simplicity, comfort is the third piece of the puzzle when it comes to the future of cooling. Any new solution that engineers design must place people at the core. It is no longer enough to design to avoid discomfort; high quality indoor environments should be the goal.

For tenants and building managers, smart, flexible cooling is transforming the user experience. With temperatures and occupancy levels fluctuating throughout the day, flexible - or even personalized - air conditioning that can respond to real time demand is vital. Technical innovations also mean that units can run at much lower fan speeds, operating almost silently without compromising performance.

Engineers are implementing control strategies that balance fan speed and valve actuators to achieve higher operational heating and cooling efficiencies. Such systems are shown to be better adapted to adjusting loads to meet variable occupancy levels and comfort requirements. Additionally, these advanced control methods can integrate with emerging SMART building management systems allowing better data and analytics to support improved people comfort while reducing the energy and carbon of the building.

The future of cooling

With the frequency of extreme temperatures increasing, our built environment needs urgent upgrades to ensure it is fit for the future. The UK government’s recent Carbon Budget and Growth Delivery Plan demonstrates that continued investment in research and development (R&D) is needed for the HVAC industry to keep finding new ways to reduce carbon and

F-gas emissions that contribute to the warming of our environment.

Innovative engineers play a critical role in creating smarter, low-carbon cooling systems that deliver high quality comfortable environments with simple, elegant design solutions. Now is the time to challenge the traditional assumptions around how buildings are heated and cooled and develop innovative solutions providing simple, low carbon comfort in a warming world.