It&#x27;s very simple: make the car so that if the tank hits empty, the car doesn&#x27;t run any more.<p>If you think that&#x27;s a problem, then please explain why this isn&#x27;t also a problem for the gas tank.  I don&#x27;t know of any cars which will continue to drive (but spewing extra toxins) when the gas or diesel tank is empty.<p>Customers don&#x27;t seem to have much of a problem topping up their diesel tank every week or two....