- USGBC requires that electrical connectors must adhere to SAE Surface Vehicle Recommended Practice J1772, SAE Electric Vehicle Conductive Charge Coupler or an equivalent regional or local standard and be capable of dynamic interaction with the utility grid.
I investigated one very common vendor, Chargepoint, and their "power management" system sort of and sort of does not comply with the requirement to interact dynamically with the utility grid. If there are several stations, the software can limit the total power available to the stations, for example one connection can have full power, if there are ten connections charging then each gets 80% of full power, twenty connections each gets 40% of full power and so on. The system does not actually interact with utility grid peak alerts in any way. Nor does my utility have any kind of peak alert mechanism that could even be used. Does such a system comply with this requirement? Other than that, the only way I can imagine to implement this is to have a building automation system chop off the power to the chargers with a crude contactor if it gets a peak alert. Either way, Chargepoint strongly cautions against using such systems on public charging stations. People charge at a public station expecting to drive away after a certain period of time. If they show up and the station is dead, or plugged in but not charging, they'll be upset. Chargepoint only recommends such demand limiting on fleet vehicles, or other situations where the electric vehicle is plugged in for a long period, such as overnight residential situations. They say a better option is time-of-use pricing to discourage use at peak times, which doesn't really implement this USGBC rule. Has anyone wrestled with this? Are reviewers enforcing this demand limiting rule? Is it enough that a charging station's software is "capable" i.e. could theoretically implement this demand limiting software if it was turned on at a future time?
Tristan Roberts
RepresentativeVermont House of Representatives
LEEDuser Expert
11477 thumbs up
January 11, 2018 - 9:10 pm
Checking the Reference Guide language, I saw this:
The EVSE must have a Wi-Fi, ethernet, cellular modem, or other Internet communication mechanism that allows the device to send usage data to a server. This enables participation in demand response programs (e.g., SmartGrid) or time-of-use pricing. Specifications must demonstrate, at minimum, that the product is IP-addressable.
The way I read it, the language you're quoting (from the changes from LEED 2009 section) is in reference to this, not to the SAE standard. And this language seems pretty flexible.
Lawrence Lile
Chief EngineerLile Engineering, LLC
76 thumbs up
January 12, 2018 - 11:01 am
Awesome, Tristan! Any Chargepoint station, or any other scheme that allows internet billing, is by definition internet IP addressable. My home charging station that just plugs into a dryer outlet is not IP addressible. So it looks like if we end up with Chargepoint as a vendor, at least, we are good to go. Tesla Supercharging stations, if I read it correctly, do not qualify for this credit, as they are not J1772 compatible.
Emily Purcell
Sustainable Design LeadCannonDesign
LEEDuser Expert
370 thumbs up
February 2, 2018 - 1:43 pm
I worked on this credit quite a bit with USGBC, and can confirm Tristan's reading. This requirement is all about anticipating future utility grid capabilities, not about prescribing specific demand response programs for vehicle charging.