jamesdifilippo
commented
5 months ago Thanks for you input!
Terminology has been a consistent issue in this space. We use nomenclature in this specification aligns with common federal definitions which define a port as the system that can charge a single EVSE (e.g. Part 680 defines port as: "...the system within a charger that charges one EV. A charging port may have multiple connectors, but it can provide power to charge only one EV through one connector at a time.")
Practically speaking, this means that the location of the port will be the same as the EVSE to which it is attached and that multiple ports on the same EVSE will have identical coordinates. From a regulator or program administrator perspective the most important information is the number of vehicles that can be actively served, not the number of specific equipment used to serve those vehicles. EVSEs may have a large number of associated ports or just one, making tracking by port the most flexible option even if it renders some information (such as location) and some metrics (such as downtime) duplicative.
We include fields for geolocation both at the port and station (location) level. Part 680 (NEVI rules) requires geolocation information about stations, but not ports which is reflected in the specification. The default for this specification is at the port level for both legacy reasons and because because it is simpler to determine the location of a specific port than to define a center-point for a station.
In terms of format, we chose to keep latitude and longitude in decimal format because it is parsimonious, flexible, easier to understand for non programmers, and reasonably simple to convert to any number of formats for spatial analysis as needed.
Again, appreciate the thoughtful input and welcome a continued discussion on these topics.
I have a couple points to raise about the latitude and longitude values in the Port specification.
First, why are these values attached to Port. A port is simply a charging cord on an EVSE and is therefore part of the Station object.
Notice my other suggestion to separate out a Charging Station Location object from the Station object.
The latitude and longitude should be related to the Location rather than to a charging cord on an EVSE. This could be defined as the latitude/longitude of the point of common coupling to the electric grid.
Finally, there is an Internet Standard - GeoJSON - for describing geographical data. Instead of having separate latitude/longitude values, it could be a single GeoJSON Point object.
I am David Herron, and have a software development contract with Evoke Systems. I'm looking at data reporting for EVSE's.