The efficiency display hasn't evolved much in the last few decades. Despite the proliferation of highly reconfigurable displays, all a driver really has to rate their efficiency is a instantaneous readout based on how far they have the pedal down at that particular moment. This is important information, but it's not the only information, and it only teaches drivers what not to do, rather then setting a good example.
We thought we could do better. While at GM, my coworker and I created a new way to communicate driving efficiency in the hopes of reducing information fatigue, giving drivers more agency over their achievements, and more easily maintaining their good behavior.
Most efficiency displays separate themselves from the speedometer, creating a new information space that drivers need to get used to. You can see this in the BMW display above, it's not clear what normal is, how whether there's a optimal, or how to achieve it.
We wanted to take advantage of drivers' familiarity with a speedometer, rather than throwing it away. The most energy is wasted, not during a single moment, but through the process of accelerating and braking, something drivers see and process through the arc of the speedo. We also knew that the human eye is drawn to things that are out of order (gaps, misalignments, equilibrium) and we're inclined to fixing it.
With that in mind, we created a information format that could be skinned across multiple brands while still retaining it's value.
Element 1 is the spatial representation of the vehicle's potential speed, defining both a minimum and maximum.
Element 2 is a simple geometric indicator. At all times, the position of the indicator is spatially and directly related to Element 1, representing the speed of the vehicle.
Elements 3 & 4 are also geometric indicators. During ideal driving, elements 3 and 4 stay uniform distances from Element 2. During non-ideal driving, the leading element maintains a uniform distance from Element 2 while the trailing element orients itself to the ideal braking or acceleration pattern based on a goal-derived driving style.
Non-Ideal Acceleration is seen here, with the trailing arc remaining at the position within Element 1 that represents an ideal acceleration pattern based on a tuned algorithm.
During ideal acceleration Element 2 maintains chromaticity similar to that of Elements 3 & 4. During non-ideal acceleration (as seen here), the chromaticity of Element 2 changes to further highlight the difference between ideal and current driving states.
And when you apply this format to an actual display, you get a more integrated, intuitive way to communicate efficiency to drivers.