What each one does
The table sets the three side by side.123
| Name | What it is | Typical job | Published by |
|---|---|---|---|
| IEEE 2030.5 | An application protocol that runs over TCP/IP and uses HTTP | Utility management of end-user energy: demand response, load control, distributed generation and electric vehicles | IEEE Standards Association. The 2018 edition is superseded by 2030.5-2023. |
| Modbus | A widely used industrial communication protocol | Equipment shares readings and accepts commands over a serial line or a network | Modbus Organization |
| SunSpec Modbus | Standard information models, meaning named data points, on top of Modbus | The same reading from different makers of inverters, storage devices and meters | SunSpec Alliance |
How the three fit together
An instruction travels from the grid side to a device in steps. Each step can use a different language.
A utility or aggregator system decides what a program needs.
The instruction reaches the site, or a system that acts for the site, over the internet. A program can name IEEE 2030.5 for this link.
A local device turns the instruction into commands for each piece of equipment.
The device takes the command over Modbus, a local API or a maker's cloud service. SunSpec names the data points where the device follows it.
Where a site controller fits
The Energy Router works on the device side of this chain. It controls the equipment at the site over Modbus RTU, Modbus TCP, local APIs and local MQTT where a supported driver implements them. It keeps operating on site when the internet drops, and new commands from the platform reach it once the connection returns. It records each command, the response and the outcome. What is an Energy Router? covers the device. Energy Router or gateway? covers the comparison.
Where IEEE 2030.5 appears in California
California Rule 21 names IEEE 2030.5 as the default protocol for utility communication with smart inverters. The California Public Utilities Commission allows other protocols by mutual agreement of the parties. SunSpec publishes the Common Smart Inverter Profile, which sets configuration requirements for an IEEE 2030.5 interface that meets Rule 21 Phase 2. A program outside California names its own requirements, so read the program's technical rules first.564
Which one does your project need
Match the need to the protocol.
| If you need to | Look at |
|---|---|
| Receive grid instructions in a program that names IEEE 2030.5 | The program's technical requirements |
| Read and control equipment on site | The equipment's own interface, often Modbus, and the driver for the exact model |
| Compare readings across makers | Whether the equipment follows SunSpec data points |
References
- IEEE 2030.5-2018, IEEE Standard for Smart Energy Profile Application Protocol. IEEE SA.
- Modbus. Modbus Organization.
- SunSpec Modbus. SunSpec Alliance.
- Common Smart Inverter Profile (CSIP). SunSpec Alliance.
- Smart Inverter Working Group Phase 2 Recommendations. CPUC.
- Resolution E-5000. CPUC, July 2019.
Common questions.
Is IEEE 2030.5 the same as SunSpec?
No. IEEE 2030.5 is a protocol between a utility or aggregator and a device. SunSpec defines the data points that equipment reports over Modbus. SunSpec also publishes the Common Smart Inverter Profile, which sets configuration requirements for an IEEE 2030.5 interface.
Is Modbus a solar and battery standard?
Modbus is a general industrial protocol. Without SunSpec, each maker defines its own register map. The Energy Router uses a driver for each family of equipment.
Does a protocol name tell me the device works?
The exact model, firmware, readings and commands still need validation. A protocol name starts the check and the compatibility list finishes it.