Justlight Energy-Saving System

The Justlight energy-saving system is a web-based exclusive application designed for building owners avoiding the peak energy usage fine caused by unnecessary energy usage. It can help users manage and check their energy usage and adjust energy usage into a low maintenance state when needed.

To comply with my non-disclosure agreement (NDA), I have omitted and obfuscated confidential information in this case study. All information in this case study is my own and does not necessarily reflect the views of Justlight.

Justlight energy-saving system concepts


Orchestrate the logic between complex relationship of each element in this IoT sensor network.

Update the old system, create controllable, sensible, and visible interfaces for the system connect to IoT devices, sensor data, and controllers, create a user-orientation system of IoT sensor network with for building owners. 

My role:

  • Web/Brand Designer

  • Product Designer

  • UI/UX Designer

  • Video Maker

  • Illustrator

The old structure


1. Lack of stratification:

The old structure put main view and area view in same level. It will cause recognition dissonance when navigate the dashboard.

2. Redundant data:

For different roles using our application, they focus on different data. Showing all data that is not necessary brings navigation load to users.


3. Unfriendly user interfaces

As well as the different device status. Users need to jump around pages to check different functional device status. It brings incomprehensive experiences, and navigation loads.  

Create different personas to reduce redundent data

Jeff, the Building Manager

"I want to know the general situation of the building in a convenient, fast way. So that I can make my hotel running depositions accordingly."


Adam, the Maintenance Tech Support

"I have more interests on detailed and specific device status, I need those information to diagnose and fix devices.


New structures of product logic

Intuitive building status

The color indicator will show the energy usage peak status accordingly. Click on single floor can easily reach to the area status.

New design of appearance & logo




The new logo is composed by a lightning bolt and a circle (resembles energy and lights), uses green, blue their mix, cyan-blue to emphasize the green energy. 

As a sovereign application will be used by building administrators, the appearance will keep bright and clean, put attentions on data itself.