Most commercial and institutional buildings already own everything they need to be flexible. The air handlers, the power meters, the EV chargers in the parkade — each of them can shift, shed, or modulate its consumption. The problem is rarely the equipment. It's the language barrier.
Building systems grew up speaking different protocols, often from different eras and different vendors. An energy platform that can't understand all of them is like a conductor who only speaks to half the orchestra. Here are the four protocols that matter most — and what each one unlocks.
BACnet: the language of the building itself
BACnet (Building Automation and Control Networks), developed by ASHRAE, is the standard protocol for building automation. If your building has a building automation system, it almost certainly speaks BACnet: air handling units, VAV boxes, chillers, boilers, and thermostats all expose their setpoints, schedules, and sensor readings through it.
For energy flexibility, BACnet is where the biggest commercial loads live. Pre-cooling a zone before a peak period, relaxing temperature setpoints by a degree during a demand event, or cycling ventilation — all of it happens over BACnet. Any serious load-orchestration strategy starts here.
Modbus: the workhorse of meters and drives
Modbus is older, simpler, and everywhere. Power meters, variable frequency drives, sub-meters, and much industrial equipment communicate over Modbus RTU or Modbus TCP. It doesn't do discovery or rich data models, but it does one thing extremely well: expose raw electrical measurements and accept basic commands.
If you want to know what a load is actually doing — not what the schedule says it should do — Modbus-connected meters are usually the source of truth. Measurement is the prerequisite of management.
OCPP: the language of EV chargers
The Open Charge Point Protocol (OCPP), maintained by the Open Charge Alliance, is how charging stations talk to their management systems. As workplace and fleet charging spreads across Canada, OCPP is becoming one of the most valuable protocols in the building: it enables smart charging profiles, load balancing across multiple stations, and scheduled charging during off-peak hours.
An EV charger managed over OCPP is a textbook flexible load — a large, deferrable draw that can be shaped around the building's peak without inconveniencing a single driver.
OpenADR: the language of the grid
Open Automated Demand Response (OpenADR), maintained by the OpenADR Alliance, is the protocol utilities use to signal demand response events to buildings: an upcoming peak window, a price spike, a request to curtail. Instead of phone calls and emails, the signal arrives machine-to-machine, and automated systems can respond in minutes.
OpenADR closes the loop. BACnet, Modbus, and OCPP give you control over your loads; OpenADR tells you when the grid needs that control most.
The orchestra, not the instruments
Here's the practical takeaway: you probably don't need new equipment to become flexible. You need an orchestration layer that speaks all four protocols natively and can act on them together — pre-cool over BACnet, verify with Modbus meters, shift EV charging over OCPP, and respond to grid signals over OpenADR, all as one coordinated move.
That's the premise Tenergen OS is built on: existing equipment, orchestrated as dispatchable flexibility, without rip-and-replace.
Start with an inventory. List your major electrical loads, note which protocols each one speaks, and you'll likely find that the flexible building you want is already standing — it just needs someone to conduct it.