Can Formula E cars race in the rain? (and other things you were too embarrassed to ask)
© FIA Formula E
© FIA Formula E

Can Formula E cars race in the rain? (and other things you were too embarrassed to ask)

Look, this comes up a lot. It’s partly because the series went a whole, solid four seasons before we finally had a wet race and also because one thing you’ll know, if you’ve ever dropped your phone in the bath tub, is that electronics and water really don’t mix. So can Formula E cars, which have giant batteries, race in the rain?

The answer is, definitively, yes. Even high voltage systems like Formula E cars use can be used in water, so long as the bits that need to be kept dry, well, are. Weirdly, that’s not the battery or even especially the motor (provided certain bits of it remain sealed) and it’s much easier to submerge an electric powertrain than it is a combustion motor.

Although generally putting either in water isn’t ideal for lots of reasons, there’s no need for an electric motor to breathe. So an EV is actually less likely to cut out, going through water, than a combustion engine – which has to aspirate, ie; needs air as much as you or I and suffers a similarly sad fate if it starts taking in water instead.

Formula E generally doesn’t have many wet events because we tend to go places when it’s summer. That’s partly because, well, it’s nicer for people to come and watch an outdoor event if it’s not going to lash them with rain and a nice upside is that it makes thermal management a big challenge. FE cars are more restricted on energy usage in hot conditions because the risk of cooking the battery under a constant cycle of energy output and input (through regen) is much higher when it’s 34ºC than if it’s twenty degrees cooler than that.

Or maybe we just like the sun. Either way, it’s unusual for Formula E to go racing below 20ºC and today’s Rome Eprix will be one of the coldest ever. That actual title goes to the permafrosted concourse of Les Invalides, Paris, where in Season 2 temperatures stayed a frigid 9ºC. It’s a relatively balmy 14ºC here, five seasons later, in EUR but nonetheless, overheating isn’t likely to be a big issue.

That means drivers have a lot more energy to potentially play with, which means they can go faster. If there’s enough grip, of course. Which on a damp-dry surface where even the straights are patchworked with new and old tarmac – like any real street surface is – isn’t guaranteed.

The varied tarmac on Rome Street Circuit – image: Inside Electric

This season each driver only gets eight tyres for a double-header event. So they can’t put new ones on to try and improve their chances of being able to use higher-power modes without risking sliding. Tyres are a big carbon cost, for racing so of course it’s important that FE puts its strategy demands where its mouth is and tells teams to work out how to use less of them but it also means, if you want to get on the full throttle of Attack Mode, you need to do it while you’ve still got the rubber to fly, not send yourself flying.

It’s very likely to be another safety car start here, before drivers will have to hang on to their cars – and their nerve – for the remaining race time. In Formula E, the driver has more information about the condition of the car than the pit wall does, which is why you often hear the engineers asking them questions you might imagine they’d know, in other series. FE cars don’t transmit very much data at all back to the garage, so all the tricky strategy calls and management lie, ultimately, in the drivers’ hands.

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Written by
Hazel Southwell