If you own a plug-in hybrid car, it’s best to drive with the electric motors as much as possible and to recharge the batteries by plugging in. That’s because the electricity provided by the power company is cheaper than the electricity produced by the hybrid’s gas engine. The power company can generate electricity far more efficiently that an internal combustion engine can, and you may also be benefiting from government subsidies through the power company. The ecOrb device is designed to tell the driver when the car is using the electric motors, and when it‘s running the inefficient gas engine.
ecOrb, pronounced “Eco-Orb,” was designed and built by Ben Kolin and his daughter after they noticed their car’s built-in monitor was lacking. Most hybrids have some sort of infographic screen in the dashboard to tell the driver what the car is doing and if they’re driving efficiently, but they’re far from intuitive. The ecOrb, on the other hand, simply sits in a cup holder and lights up with different colors depending on the driving mode. It’s a far more user-friendly way to monitor your driving than the built-in infographic most cars have.
All cars since sold in the US since 1996 have a convenient OBDII port, which can be used to gather a wide range of information about the car’s current operating status. That includes the engine’s RPM, which will read as zero in a plug-in hybrid that’s running on the electric motors. ecOrb connects to an inexpensive OBDII Bluetooth tool through an HC-05 Bluetooth module. That module, in turn, passes data to an Arduino Pro Mini. The Arduino changes the colors of an RGB LED based on that data. A total of four modes are displayed, based on if the car is moving and if the gas engine is turning. All the driver has to do is pay attention to the status and try to remain in “car moving, gas engine off” as much possible.