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Our API has been thoughtfully designed with an eye towards the OpenADR specification, which is a widely recognized standard in the energy sector. We deeply respect and admire the thoroughness of OpenADR, and we have embraced many of its terminologies and concepts. However, in striving to provide an API that is highly accessible and tailored to the diverse needs of our partners, we have opted for a more streamlined approach at this stage.

This streamlined approach enables quicker integration and facilitates flexibility, which we believe is crucial for innovation and adaptability in the rapidly evolving energy landscape. We are, however, very much open to the evolution of our API. As we continue to listen to and learn from our partners, we remain receptive to incorporating more elements of the OpenADR specification in the future, if it aligns with the needs and goals of our community.

The following glossary provides a brief overview of the terminology used in our API. For a more in-depth look at the OpenADR specification, please refer to the OpenADR Alliance website.


Virtual Top Node

In essence, this API is a virtual top node (VTN) server. The role of a VTN is to monitor the needs of the grid and send out signals to the virtual end nodes (VEN) with requests to act on their energy resources. The VTN is also responsible for receiving reports from the VENs about the actions taken in response to the signals.

Virtual End Node

You as a partner are responsible for the implementation of a "virtual end node" (VEN) client. The job of a VEN is to receive signals from the VTN and deciding how to act on those signals. Whenever a VEN server receives a signal from the VTN, it should respond with a report about the actions taken in response to the signal. It should also send out reports about the state of the energy resources it controls on a regular basis.


The signals sent out by the VTN are called events. An event is a simply a request for a VEN to act on various energy resources. It is up to the VEN to decide how to act on the event, and they are free to ignore the event if they decide that it is not in their best interest to act on it.


The VEN should respond to events by sending reports to the VTN about the actions taken in response to the event. They should contain information about what energy resources were affected and how they were affected. In addition to reports about events, the VEN should also send out reports about the state of the energy resources it controls on a regular basis.

We use the reports to monitor where we have capacity to influence the grid and to verify that VENs are acting on the events.


A resource is any energy resource that the VEN can control (e.g. electric vehicles, hot water heaters, solar panels, thermostats, etc). Each resource has a unique identifier that is used to identify it in the API which the events and reports will also refer to.