FAQ NRV balance traffic light

On what basis is the NRV balance traffic light calculated?

The quotient is calculated from the moving average of the German NRV balance of the last 5 minutes and the secondary control reserve (SRL) and minute reserve power (MRL) dimensioned for the German NRV. For this purpose, the positive dimensioned SRL and MRL are included for a positive NRV balance (system under-covered) and the negative dimensioned SRL and MRL are included for a negative NRV balance (system over-covered).

The level of the quotient determines which traffic light color is published (see below).

Operational values are used to calculate the NRV balance for publication. If errors occur, the NRV balance traffic light is not published in order to avoid providing incorrect information.

When will which traffic light color be released?

If the quotient of the German NRV balance of the considered interval and the SRL and MRL dimensioned for the German NRV is less than 0.6, a green traffic light signal is transmitted (unsigned). If the quotient is greater than or equal to 0.6 and less than 0.8, a yellow signal is transmitted (with sign). If the quotient is greater than or equal to 0.8, a red signal is transmitted (with sign). A positive sign indicates a positive NRV balance (system undercovered) and a negative sign indicates a negative NRV balance (system overcovered).

How often is the traffic light updated and with what delay is it made available?

The traffic light is recalculated and published every minute. As a rule, there will be a delay of 2 minutes between the end of the time interval taken into account and the publication of the signal.

How is the NRV balance traffic light published on the grid transparency?

The latest value is displayed in the form of a five-stage traffic light. This is updated automatically once a minute without the page having to be reloaded. The timestamp of the interval taken into account is also shown, with the time being the end of the corresponding time interval.

The values are also displayed in the form of a bar chart, with the green bar displayed in positive and negative directions. To update this display, the page must be reloaded.

Can the historical values of the NRV balance traffic light also be called up?

The NRV balance traffic light values are kept for the period from the date of publication. They can be downloaded as a csv file or accessed via the API.

Taking into account the limits described above (see "When is which traffic light color published?"), the following values are returned: RED_POS, YELLOW_POS, GREEN, YELLOW_NEG, RED_NEG. A positive sign indicates a positive NRV balance (system undercovered) and a negative sign indicates a negative NRV balance (system overcovered).

In addition, the numerical value of the NRV balance can be called up as usual as a 15 min value on netztransparenz.de.

Is the value of the NRV balance traffic light also made available via a Web API endpoint?  

The NRV balance traffic light can also be retrieved via the programming interface using a Web API endpoint. Registration is required in advance to use the Web API. After subsequent confirmation by the transmission system operators, the Web API can be used.  

What values are returned by the Web API?  

Taking into account the limit values described above (see "When is which traffic light color published?"), the following values are returned: RED_POS, YELLOW_POS, GREEN, YELLOW_NEG, RED_NEG. A positive sign indicates a positive NRV balance (system undercovered) and a negative sign indicates a negative NRV balance (system overcovered).