Real-Time Device Overview

The real-time device overview is located at the very top of the device page and displays the current energy flow between connected devices.

Written by Vincent Moser
December 23, 2025

Overview: How energy flows through your home

With the Live Device Flow in the Ostrom app, you can see at a glance how electricity is currently flowing through your home – from the PV system to the battery, through the grid, and into your consuming devices. The visualization is in real time and helps you understand and optimize your energy usage transparently.

Layout of the Device Overview – What goes where?

The structure of the energy flow display is standardized:

• Top: Photovoltaics (PV)

• Left: Grid – displays grid import or export

• Right: Battery – in charging or discharging mode

• Bottom:

• Household – current total electricity consumption of the entire household

  • Only enabled if the customer has connected a dedicated meter device.
  • Devices (Plug icon) – current total consumption of all connected consumer devices (HVAC, EV/wallbox)
    • Displayed when the customer has not connected a dedicated meter device, as we otherwise have no information on the overall household consumption.

• Below the household:

  • EV (Electric vehicle) – indicated by a car icon
  • HVAC (e.g. heat pump) – indicated by a heating icon
  • Remaining household usage – indicated by a light bulb icon

Important: Only the devices and categories that are actually connected are displayed. If, for example, no battery is shown, it either has not been connected or we have not detected a connection. If a device is connected but still not shown, it is likely a technical error (bug).

Example view with all supported device categories connected:

What does the overview display?

The device overview shows the real-time energy flows between connected components. The following information is shown:

For each main element (PV, Grid, Battery, Household):

• Power output (in kW) directly below the icon – if multiple devices exist in a category, the value shown is the total (e.g. combined production from multiple PV systems).
• Timestamp above the overview – indicates when the measurement was last received (clock icon).
• Connection animation between devices – if energy is actively being exchanged, this is visualized with animated lines.

Visual behavior and color coding of elements:

• Producing devices: dark green / dark teal
• Consuming devices: light green / light teal
• Grid:
  • Import: dark green / dark teal
  • Export: light green / light teal
• Battery:
  • Charging: light green / teal
  • Discharging: dark green / teal
• Inactive devices (no measurable load): gray
• Energy flow:
  • No flow detected: no animated connection
  • Flow detected: connection line between device categories with animated direction of flow

Behavior on data changes

• The overview does not update automatically if you remain on the page.
• An automatic update is triggered when restarting the app or navigating away and back.
• To manually update: swipe down on the device page.

Requirements for displaying Household and Grid

To correctly display household and grid data, a separate energy meter must be connected.

• Currently, only meters installed together with the PV system are supported.
• You can check whether such a meter exists by attempting to connect one via the app. You will need the login credentials for your PV system account.

Note: If no meter is connected, only the total consumption of connected devices is shown (e.g. EV or HVAC), but not the total household consumption or grid import/export.

Example view if no meter is connected:

Errors and Offline Indicators

If a device has not connected within the last 20 minutes, it will be highlighted in red with a connection icon.

• If all devices in a category are affected, the category is marked as “Offline.”
• If some devices still report valid data, their values are still shown instead of marking the whole category as offline.

Example view with error and offline indicators:

Manual Refresh

• Manual refresh via swipe is possible, but limited to a certain number of attempts per hour (depending on device type and provider).
• Excessive updates may trigger a temporary lock, and you’ll see the message “Update failed.”
• A new update is usually possible again within 1 hour, often sooner depending on previous refresh frequency.
• Even after a successful refresh, there may occasionally be delayed data. In such cases, the values should update after another manual refresh within a minute.

Common Limitations and Notes

• Some heat pumps (HVAC) currently do not provide consumption data – in such cases, the HVAC category will be displayed as "Offline".
• Household consumption may be incomplete or inaccurate if, for example, batteries or inverters are not connected.
• If only individual devices are connected, energy flows may not be displayed meaningfully. For example, if a PV system and a single EV are connected, but the EV is not currently charging, no energy flow will be shown from the PV to the EV. Even though the PV is producing energy, we do not display any other flows (e.g. to the grid or household) because we lack visibility into where the energy is going. Without additional devices like a battery, energy meter, or other consumers, the system cannot determine how the PV energy is being used.
• Electric vehicles and heat pumps sometimes do not send regular updates every 20 minutes. As a result, it is common that they are displayed with a red error indicator or as “Offline,” even though everything is functioning normally. This behavior is generally unproblematic and represents the expected state.