In order to display the self-consumption, an additional meter must be connected to the e.manager.
You can choose between two types of meter (total consumption and residual feed-in/subscription meter).
In each system, either a total consumption meter or a residual feed-in/subscription meter may be installed.
Residual feed and reference meter
If you have installed a 2-direction meter (feed-in and purchase). The self-consumption and the total consumption are calculated from these two values, plus the PV power. If you have only installed a residual feed meter, without a reference meter, only the self-consumption can be calculated. A calculation of the total consumption is not possible.
In order for the self-consumption to be displayed in the virtual plant, you must also add the meters to your plant. Make sure that you add the correct meter. By default, two digital inputs are preconfigured as residual supply and reference meters. If you have connected the meters to other inputs or via LAN or RS485 to the e.manager, then the two meters (PIC 1 and PIC 2) must not be in the system.
Total consumption meter
If you have installed a total consumption meter, the other measured values can be calculated from this measured value (purchase, feed-in, own consumption).
However, this calculation must be performed for each 5-minute value. In the day view, this is calculated automatically. In the monthly and yearly view, the effort would be extremely high and would take too much time. Therefore the calculation is done directly on the e.manager (from version 0.8.0).
For this purpose the system automatically creates so called "counters". For these virtual counters the measured values are calculated every few seconds and also transmitted to the internet portal. These counters can be easily identified by their serial number, starting with "Counter-" and the port "Logger".
Please add the following devices to your system under Configuration → Inverter → Add Device:
- Your total consumption counter (digital input, RS485 or LAN)
- Counter-20 Total consumption
- Counter-14 Residual feed-in
- Counter-16 Reference
By default, two digital inputs are preconfigured as residual supply and purchase counters. These must not be included in the virtual plant.
If the e.manager has not yet transferred any counters, please restart it
The following outputs/events are displayed in the daily graph for self-consumption:
- Generation: The yield of the PV system
- Self-consumption: The yield that is directly consumed from the PV system.
- Residual feed-in: The yield that is fed into the public grid.
- Purchase: The yield that is drawn from the grid.
- Total consumption: The total consumption, i.e. own consumption + purchase.
If you monitor other generators (CHP, small wind turbine) or consumers (heating element, washing machine, ...), these are also displayed here.
The gray area 1 indicates the max. inverter power in %. If you use e.g. the 70% regulation, then it should always be at 70%. If you have activated the item "readjust", then you can see here how the device readjusts the max. inverter power by increasing the allowed maximum. This does not automatically mean that the PV power must also increase. It just means that there is a possibility to produce more. But if there is not enough sun, the PV power will not increase.
The black lines 2 shows when a rule has been executed on the e.manager. If you move the mouse over, you will see the name and time. For this, the rule must have a name in e.manager.
The relays are shown under point 3. If the curve is up, the relay is active, if curve is down, the relay is off. For the relays to be displayed, they must be added to the system.
For correct display, the e.manager must have software version 0.9.0 or higher.
The power values displayed are 5 minute averages. The rules and the max. inverter power are always calculated on the device with the actual power. Therefore, deviations between the real values and the curves may occur.
Profit / Costs in Euro
In the legend the profits / costs are shown in Euro. For this, the feed-in tariff and the costs for the purchase must be specified. Please enter these values under "Configuration" => "Inverter".
Under Purchase the costs are displayed which you incur when you purchase electricity from the public grid. Behind it is indicated how much you have to pay for one kWh.
Residual feed (profit)
Here you can see the profit that you have earned from the PV system. If you use part of the electricity yourself (self-consumption), then only the part that you feed into the public grid and for which you also receive payment from the energy supplier is displayed.
Own consumption (saving)
In the case of self-consumption, it is calculated how much you have saved through self-consumption.
- 28 cents/kWh for the purchased electricity.
- 12.5 cents/kWh remuneration for the electricity of the PV system
If you now have 50 kWh on your own consumption, then you save the difference between purchase costs and feed-in tariff.
50 kWh * (28 Cent/kWh - 12,5 Cent/kWh) = 7,75 €
i.e. you have saved 7,75 € by using your own electricity.
Total consumption (cost)
The total consumption cost is made up of the cost of purchase and the cost of self-consumption. The self-consumption costs are made up of the kWh times the feed-in tariff.