Passengers might be the most under-appreciated factor in how much fuel and money you waste. As I write this, for example, a business headline boasts of Toyota’s multi-million-dollar plan to boost fuel efficiency by 25 percent, with the usual discussion of what this will mean for the economy and the climate. Any of us, however, can boost the efficiency of our cars by several hundred percent instantly, with no additional expense or technology, simply by getting more people in the car.
This fact is also forgotten when we judge car owners by the wastefulness of their vehicles. An SUV is a spectacularly inefficient machine compared to a Prius, for example, but pack that Dodge Durango full of people and suddenly it is greener than the electric hybrid driven alone.
To use another example, your bus could be less efficient than an SUV in kilometers-per-litre, yet all of you bus passengers are making one of the greenest transportation choices around, thanks to the fact that so many seats are filled.