A trust-first concept for Enpal's subscription solar model.

Users should always know what is happening at a glance. The original app required users to interpret kWh figures to understand system health, putting the cognitive work on them. The concept makes system status and financial outcome immediately visible without any interpretation required.

Savings in euros as the hero metric, not production in kWh. Weather context (“Sunny today”) explains why today's numbers look the way they do — removing the anxiety of “is this normal?”

Users shouldn't have to remember what they were promised at installation and compare it to what the app shows. The concept makes the comparison explicit and persistent — the original sales forecast becomes a benchmark the app tracks against automatically.

The payback progress bar is the most important element. It gives users a single, trackable answer to “was this worth it?” that doesn't require any calculation on their part.

Users shouldn't have to interpret what a number means — “94% efficiency” only tells them something if there's a consistent reference point. The concept establishes “expected output” as that reference, so every reading is automatically contextualised against the forecast the system was sold on.

The headline is always a verdict, not a metric. “Everything is running optimally” — not “94 kWh.” The number supports the verdict; the verdict doesn't require interpretation.

When errors occur, users need to know three things: what happened, whether it affects their savings, and whether they need to do anything. Each alert tier answers all three in one glance. Savings figures differentiate per state (€42 / €28 / €12) so users understand the financial impact of an issue — not just its existence.

Coral (#ffd0d0) was chosen over alert red (#ff0000) for the critical state. Red feels alarming and erodes trust — precisely the opposite of what the app should do when a homeowner sees an alert on a system they paid €20k for. Coral communicates urgency without panic. And “No action is needed from you” on the amber state removes anxiety at exactly the moment it would otherwise spike.

Forward-looking data reduces the anxiety gap between monthly bills. Users who can see projected savings don't need to wonder whether their system is underperforming during winter — the app tells them before they have to ask. This is visibility extended into the future, not just the present.

Pairing financial projection with CO₂ offset tracking. Users who aren't motivated by money alone can see their environmental impact — and users who are focused on ROI get a forward-looking number that keeps them engaged between bills.

Users need to control what they've seen. The dismiss flow gives them agency over their notification list, while the system communicates proactively so users don't need to manually check for issues. The System Health card on the Home screen is tappable and navigates directly to Notifications.

The empty state is deliberately reassuring: “All caught up!” closes the loop. It tells users there's genuinely nothing to worry about — not that the system has stopped communicating. Severity is communicated through icon circle colour, not left border bars (which clipped against rounded corners while building the prototype).