Air conditioning maker Daikin Industries has developed a refrigerant for electric vehicles that it says can increase their range by up to 50%. By 2025, Japan’s largest air conditioner manufacturer hopes to get the product to market. But will it be taken up by the auto industry?
According to Nikkei Asia, Daikin says that a car with a range of 200 km on a full charge may drive an additional 100 km with the new refrigerant in an EV with the air conditioner running and operating in an urban area.
It’s a development that could mean big things for the EV industry, for a couple of reasons.
While many modern electric vehicles can travel from 300-400km on a single charge, many people consider they need more driving range.
Although realistically most people drive no more than 40km a day, “range anxiety” has been repeatedly listed as a key barrier to uptake in multiple studies.
But this problem could theoretically be solved for a relatively small sum. Currently, the most common refrigerant for use in EV air conditioners is a chemical patented jointly by Honeywell and Chemours in the United States which reportedly costs roughly $A360 per car.
Additionally, a 2019 IEA report titled “Cooling on the move – the future of air conditioning in vehicles” notes that automotive air conditioning accounts for the equivalent to the consumption of some 2 million barrels of oil per day, or 1% of global energy-related CO2 emissions.
And, as many EV drivers know, air conditioning can be a range-killer. It’s why Tesla moved to a heat pump in the Model Y and then the Model 3.
The IEA report notes that, “Improving the energy efficiency of MAC and transitioning to refrigerants with a GWP of less than 1 would avoid more than 950 MtCO2-eq in overall MAC-related GHG emissions, or the equivalent of almost 1% of global energy-related CO2 emissions.”
How does Daikin’s new product reduce energy consumption?
The heat generated by compressing the refrigerant is used to heat and cool the air within the vehicle. The boiling point of Daikin’s new refrigerant is around minus 40 Celsius, which is 10 to 15 degrees lower than the previous product. As a result, the amount of power required for compression is reduced.
It seems to be a promising development, says Haitham Razagui, editor of specialist automotive thermal management journal SightGlass News and communications director for air-con industry body VASA, in a note by email to The Driven – but there are a few catches.
“For some time it’s been clear that refrigeration/air-con technology will become central to any EV thermal management system. Tesla’s Octovalve (heat pump) is a really elegant way of achieving that,” says he says.
“However, the refrigerants suited to automotive applications haven’t necessarily been that effective for heat pumps and vice-versa.
“A few car companies have tried using carbon dioxide (called R744 when used as a refrigerant) but the downsides are incredibly high operating pressures but which seem to have caused a lot of failures.
“For example, I know Mercedes-Benz has ditched R744 from European market cars and some models with this refrigerant ended up exported to the Middle East where the air-con just doesn’t work and the whole system would have to be replaced with one compatible with synthetic refrigerants.
“A small number of these R744 cars ended up as grey imports in NZ with broken air-con and a big bill to get them working again. Only one repairer in the whole of NZ could do the work and it wasn’t easy,” Razagui says.
He notes that R744 works well for automotive heat pumps (and has been used as such by some European brands) but it doesn’t work well if outside temperatures are in the mid-30 Celsius range or above.
A refrigerant that operates at more normal pressures, doesn’t damage the ozone layer or contribute to climate change, works well in both air-con and heat pump applications and is compatible with a system that is subject to the harsh environment and vibration of a moving vehicle, AND reduces energy consumption hence increasing driving range is something of a silver bullet, Razagui says.
But the question is, will risk-averse global car manufacturers adopt it?
Because carmakers would likely want to put a new refrigerant through exhaustive tests before using it, and some will dislike the fact it probably has a patent on it and therefore comes from a single source, meaning they have no negotiating power on price, it’s not likely in the short term – unless legislated.
Is there a better solution already?
Razagui notes that the current refrigerant commonly in use in Australia is known as R134a. However, there is a more recent type known as R1234yf, which replaced R134a due to the latter being 1400 times more potent as a greenhouse gas than CO2.
While it doesn’t offer the same range-increasing potential as Daikin’s new solution, R1234yf would still be better for reducing air-con-related automotive carbon emissions
But because R134a is not banned in Australia, and R1234yf is more expensive, the former is still used by carmakers for locally sold vehicles – including electric vehicle makers, he says.
Bridie Schmidt is lead reporter for The Driven, sister site of Renew Economy. She has been writing about electric vehicles since 2018, and has a keen interest in the role that zero-emissions transport has to play in sustainability. She has participated in podcasts such as Download This Show with Marc Fennell and Shirtloads of Science with Karl Kruszelnicki and is co-organiser of the Northern Rivers Electric Vehicle Forum. Bridie also owns a Tesla Model 3 and has it available for hire on evee.com.au.