Maxem Go, the smart device for charging your electric car on your own solar energy.
Cohere's mission is to make homes smarter, cheaper and 100% sustainable. They do this with their product Maxem, an energy management system. It measures and sends power.
With the Maxem you can view your house’s energy consumption and the charging process of your electric car and solar-energy. The user can also manage how to charge his car. For example, only charging on the power of his solar panels.
For the minor User Experience Design at the University of applied science Amsterdam I got the assignment to design the interface for the Maxem. The interface had to support the goal of Cohere and the Maxem.




The solution, Maxem Go
The goal is to charge the car on as much energy as possible from the house owner’s own solar panels. To achieve this, the car needs to be charged for longer period of time, because the more solar energy will be available in the meantime.
The solution is the Maxem Go, the smart device for charging your electric car on your own solar energy. With the Maxem Go, the user decides when the car must be fully charged. Maxem calculates the amount of solar energy the car can be charged with based on the weather forecast and expected sun hours. The Maxem Go comes with an app.






Why a device?
With the Maxem I want to change the behavior of the user. I want the user to set the time to his needs every time he charges his car. The user needs to be triggered. The user sees the device every time he charges his car. We remember to do something more likely when it is in plain sight. Therefor the user is more likely triggered to take action.
Also, according to the Fogg behavior model the trigger to do an action can either succeed or fail depending on the users motivation and the ability to perform the action. The action here is to set the time. A mobile app can hinder the user in performing this action. It can be empty, lost or be left somewhere. Using the app cost more time, and might be for nothing, like when the home battery got enough energy to charge car fully, lowering the motivation to open the app (the next time).
Building the prototype
A paper or digital prototype wasn’t enough to make the concept clear, so I build a prototype. It was basic prototype without a screen or button, but it was enough to communicate and test my idea. The user could rotate the prototype. A laptop with the device’s screen was behind it and interacted with the prototype. I used an Arduino with a servo to read to rotation and a serial wireless WIFI module to communicate with the app on the laptop.





