Sometimes the best ideas are also the simplest.
That was our first thought on seeing one gas-saving idea from nothing less than an oil company in South Korea.
Called the HERE balloon, it's oil giant S-Oil's way of reducing the time drivers spend looking for a space in a large parking lot--and therefore, the gas they waste while doing so.
It's amazingly simple. Bright yellow arrow-shaped balloons are tied to every parking space.
When a car is parked, it pulls the balloon's tether down so it's not visible to those scanning for spaces. But in empty spaces, the balloon is high enough that it can be seen across a parking lot--making it easy for drivers to spot all the unoccupied spaces.
S-Oil estimates that the average driver in South Korean capital Seoul drives for a full half-kilometer each day looking for a space. Over a month, that's 15 kilometers (9.3 miles) per car, used for nothing more than parking--and that can mean a whole liter of gas wasted.
With the balloons, S-Oil says that in just one day, in one parking lot, 700 cars used 23 liters (6 gallons) less oil. Multiply that across more parking lots and more days and you can see the cumulative benefit.
It's not a perfect solution, for a few reasons.
One is that helium never stays in balloons for long, requiring constant refilling of a rare, non-renewable gas valuable for more important medical and scientific resources. The other is that it's almost inevitable that at some point, a kid will come along with a pair of scissors and release them all into space...
Even so, we like it, and it's a satisfyingly low-tech, low-hanging fruit solution to the problem of saving gas.
[Hat tip: John C. Briggs]