Air Conditioning and the Environment

Environmentally conscious end users make some responsible choices when they can. They lower their thermostat in the winter and raise it in the summer. This decreases their energy use (with the additional perk of lowering their power bill). Other personal changes include switching to an energy-efficient heating, ventilation and air conditioning (HVAC) system, replacing windows with multiple-panes glazing, and sealing and insulating ducts and water heaters. 

But there is only so much anyone can do, when there are significant problems with the products they have in their homes: air conditioning can use a refrigerant that’s harmful to the environment and it uses a lot of electricity (which is often produced by burning fossil fuels). 

Very small steps 

CFCs and HFCs are cooling agents used in air conditioners. They both create gas by-products with CFC increasing holes in the ozone layer and HFC contributing heavily to the greenhouse effect. CFCs have been banned and are not used in any new systems while HFCs are currently being phased out. This is a huge step forward. But the electrical grid is still feeding these systems at an increasing rate.  

Heating, cooling, and ventilation add up to over 25% of electricity used in the U.S. commercial sector alone. In U.S. households, this number rises to over 50%. According to the IEA, there were 1.6 billion HVAC units in the world in 2018. They were predicting that this number would grow to 5.6 billion by 2030 due to improving income and living standards in many developing countries. CNBC quoted this increase as potentially reaching 14 billion by 2050. 

Four years ago, air conditioners and electric fans already accounted for about 20% of the total electricity used in buildings around the world (10% of all global electricity consumption at the time) and AC use will likely be the second-largest source of global electricity demand growth (after the industry sector). 

Predictions 

Air conditioners alone produce enough heat to increase urban temperatures, while still emitting very potent greenhouse gases. And, as the planet warms and the growing economies invest in more air conditioners, this will increase the global electricity demand even further, reaching nearly a quarter of the current global electricity consumption by 2050. 

The IEA predicts that “(w)ithout major efficiency improvements to cooling equipment, electricity demand for cooling in buildings could increase by as much as 50% globally by 2030.” According to their 2020 report Cooling Emissions and Policy Synthesis Report: Benefits of cooling efficiency and the Kigali Amendment, “direct and indirect emissions from air conditioning and refrigeration are projected to rise 90 per cent above 2017 levels by the year 2050.”1 

This was one of the reasons for the Global Cooling Prize, a USD 1 million competition to design a single-room air conditioner that produces five times less greenhouse gas over the course of its lifetime than a standard unit. Participating designers, in many cases, tried to combine lower energy consumption with a climate-friendly refrigerant instead of focusing on one or the other.  

The IEA report quoted above predicts that if we use more energy-efficient technology while transitioning away from polluting refrigerants, we could avoid up to 460 giga tonnes of carbon dioxide equivalent (GtCO2e) over the next four decades (which would be 4-8 years of emissions based on 2018 levels). What’s more, doubling the energy efficiency of air conditioners could also save up to USD 2.9 trillion by 2050 (in the form of reduced generation, transmission, and distribution costs alone).  

But, as it stands, the current AC technology hasn’t really changed that much in over 100 years. We need significant improvements to the technology, and the motors and pumps used in it.