Hydrogen Cars in Winter: Will Exhaust Cause Roadway Ice?

There are a number of questions many people have about using H2 in fuel cells in the cold

If hydrogen fuel is ever to become a mainstream strategy for powering vehicles for transport and transportation, then it needs to be able to withstand the types of temperatures to which vehicles will be exposed.

In many parts of the world, winters drop well below freezing

In a fuel cell, hydrogen fuel is combined with oxygen in order to produce electricity but not carbon emissions. Projects are underway to study H2 in powering everything from passenger cars and transport trucks to airplanes, container ships, trains, buses, and heavy-duty machinery. As a result, the companies, organizations and teams working on those projects need to be confident that the outcome of their work will be usable year-round. According to Ballard’s “Fuel Cell Electric Buses: Cold Weather Operation” technical note publication, according to that company’s research, fuel cells will produce electricity by combining the oxygen and H2 without emissions at any temperature. That said, there is a difference between producing the electricity and doing so without losing performance. That same document shows that performance doesn’t degrade within the range of -30ºC (-22ºF) and 45ºC (113ºF). https://youtu.be/BXr2kCl8h1E?si=Xl9LKo7V87pCIK0U

Of course, performance isn’t the only factor for hydrogen fuel in winter

Among the other issues that have been voiced with respect to using H2 in fuel cells during the winter have to do with the exhaust that is produced. It’s not carbon dioxide or other greenhouse gases but is instead water.  While water is something that occurs all the time in nature and isn’t typically considered concerning as an emission, some have wondered about what happens when all those vehicles produce emissions that freeze. For instance, will ice buildup occur in a cold water vapor exhaust system or will it lead to sheet of ice forming on roadways?

Experts aren’t concerned

Those with experience with hydrogen fuel cells aren’t concerned about this issue, and there are many reasons for this.  The first is that they know that conventional gasoline-powered internal combustion engines already produce a certain amount of water vapor in their emissions, and this is not a problem in those systems. The next is that those familiar with fuel cells understand the volume of water vapor that is being produced by the systems. Unless the exhaust pipe for the water vapor were to be pointed directly down at the road and positioned close to the road surface – a design that is neither practical nor under consideration by any known vehicle manufacturer – then it won’t end up on the pavement in any meaningful way. It is, after all, warm as it leaves the exhaust and disperses in the air in the same way as water vapor from human exhalation.