During the recent heatwave, Mira - the Motor Industry Research Association - was challenged to show how cars could be cleaned in future summer droughts.
Their design works like a dishwasher, using a mix of steam and water mist.
The inflatable car wash unit uses just four litres of water, compared to the 135 used in a hosepipe soaking.
Mira was commissioned by EBay Motors to come up with a solution to what could be a common problem in future - helping proud drivers to keep their cars sparkling clean while observing a hosepipe ban.
Derek Charters, a senior consultant at Mira, said: "One hot summer day, we had a thought shower - we don't like to call them brainstorms anymore.
"There were a number of ideas that we considered - cars that came with paint that never needed cleaning or even a process in which thousands of polyester balls are fired at the car to act as an agitator.
"But this was the best idea and the beauty of it is that is uses just four litres of water, which can be filtered off and used again afterwards. Depending on whether you have used a biodegradable detergent, you may even be able to use it to water your garden."
And Mr Charters, who himself confesses that he chose the colour of his grey Fiat Multipla because it doesn't show the dirt, can see a day when Sunday in the suburbs starts with car drivers inflating up their car wash units.
"I'm sure it may start off just being used by commercial operators, maybe when you drive to the local supermarket, but it could quickly become an aspirational item, just like dishwashers in the kitchen. You'll just be able to zip your car in and come back an hour later to a clean car."
Paul Regan, editor of the BBC's Top Gear website said it might not quite excite the interest of his TV colleague Jeremy Clarkson: "It's a nice idea, but putting up a tent on your driveway every time you wash your car might put people off. Especially when you can already just go to the garage and have your car washed for you - most of the time using recycled water.
"You could always save a few litres simply by using a bucket - and not washing your car as often."