Smart Charging
Shifting EV charging demand to off-peak hours for grid stability and rewarding drivers with financial benefits.
Role
UX/UI Designer
Company
Deftpower
Platforms
Android & iOS
Year
2024 - 2025
As electricity usage increases, particularly with the growing popularity of electric vehicles (EVs), the power grid is experiencing strain during peak hours. This surge in demand can lead to instability, affecting both the reliability of our energy supply and the overall performance of the grid. Deftpower’s Smart Charging solutions are designed to incentivize EV drivers by offering cashback rewards for charging during off-peak hours, encouraging flexibility.
The Challenge: Unfamiliarity & Complexity
When I joined the Smart Charging project, the main issue we faced was that the technology was incredibly powerful, but the human experience was non-existent. User Insight: Drivers primarily care about the cost and state of charge by departure time. They do not want to manage complex schedules or worry about empty batteries.
Goal 1 | Goal 2 | Goal 3 |
|---|---|---|
Make energy optimization automatic but transparent. | Maintain user control to relieve anxiety and uncertainty. | Visualize charging schedules and rewards to increase adoption. |
Initial sketch exploring the core interaction model.
UX Decisions: Control, Trust, and Feedback
A. Single Point of Control: Departure Time
To enable Smart Charging there are two data points needed: State of Charge (SoC) and when the car is needed again. Though flexibility is important, offering too many settings will overload the user.
Decision: The departure time is the most important user input.
The app would use AI to predict the departure time when plugging in (f.e. ‘07:30 tomorrow’).
The user’s primary task is narrowed down to a simple confirmation or override: ‘Tap to use prediction’, or ‘Tap to override time’.
Key user input: the departure time with AI option.
B. Anti-Anxiety Option: The Override
One of the biggest killers of smart charging adoption is anxiety. If a user feels unsure of whether their battery will be fully charged for an unexpected trip, they will disable the feature.
Decision: A clear ‘Charge immediately’ option is always accessible on the main charging screen.
Behavior: Tapping this option would immediately switch from the smart charging schedule to prioritizing immediate charging at the current rate.
Feedback: The UI immediately updates the charging schedule and removes the estimated rewards, affirming the user’s control while maintaining transparent about the financial trade-off.
Final UI design emphasizing the two primary user controls: Smart Charging Departure Time and Charge Immediately override.
C. Visualizing the 'Valley' and Rewards
The biggest incentive for users to activate smart charging is the rewards program. Showing real-time rewards and charging schedules will serve as a motivator for feature adoption, transparency and trust.
Decision: We designed a charging schedule that visualizes the price valleys and included a reward estimation.
The Schedule: A simple, scannable graph shows the planned charging periods (the ‘valley’ - cheapest off-peak hours) against the plug in and departure times. This helps explaining to the users when and why the charging is paused.
Estimated Reward: A dedicated pill on the main charging screen shows the estimated reward for the session. This is both crucial during smart charging and to motivate users to switch from immediate charging to smart charging. This is a crucial piece of information that turns a passive feature into an active benefit.
Visualizing the ‘Valley’: Showing the user exactly when the charging is planned and how it is avoiding peak hours.
Impact & Learnings
The successful launch and adoption of the Smart Charging feature across the initial pilot areas validated our user-centric approach. By focusing on simplified input, transparency, and user control, we were able to onboard the first dedicated users. By making continuous improvements we proceed to make smart charging more accessible and rewards more impactful.
Metrics & Results
Push Notifications: 33.6% of users that opened the push notification converted to start a smart session. This validates the simplicity of the main smart charging screen.
Return Rate: 62% of smart charging users return after the first session. This shows a good balance between simplicity, automation, and pay-off.
User Savings: On average smart charging users earn € 4,85 per week in rewards. Transparency built trust and drove retention.
Adoption Rate: Seamless integration and collaboration leads to increasing adoption among white-label partners. Simplicity is key; the feature was easy to use, not just available.
Key Learning: For complex and automated projects, UX is more about removing friction and instilling trust than in adding options, settings, and features. We succeeded mainly because we turned a complex energy problem into a single simple question for the user: ‘ When do you need your car?’.
