Tuesday, August 30, 2011

Energy Efficient Intersection

Construct intersections with small hills exactly where cars will have to stop for stop signs.  The car will move up the hill while stopping, and roll down the hill while accelerating.  This would ease the wear on brakes, and contribute to better fuel economy during the most fuel-intensive part of driving: acceleration from a standstill.

If a 3000 pound car where to stop from a speed of 25 miles per hour while climbing a 12-inch hill, the hill would absorb 5% of the required braking energy.  Rolling down the other side would immediately contribute 5% of the energy required to accelerate back to 25 mph.

CATEGORY: Transportation, Energy, Construction
IDEATION: December 2010


  1. This would make police chases far more exciting.

  2. Yes, the angles and design would definitely need to be optimized. The approaches should probably be longer and shallower; but the higher the bump is, the more worthwhile it is energy-wise.

  3. Also, another factor is the amount of traffic. Cars should not be lined up on the up-hill portion, or you would probably increase energy use. I think the ideal implementation would be at mid- to low-traffic intersections where multiple cars would rarely be lined up on the up-hill slope.