Power Monitor MQTT Publisher for macOS

A script that retrieves power value (W) from the SAP Power Monitor app for macOS and publishes it to an MQTT broker.

Features

• Power value (W) retrieval from SAP Power Monitor
• Automatic MQTT publishing
• Test mode, single-run mode, and continuous monitoring mode

Requirements

• SAP Power Monitor
• Homebrew

Installation

Prerequisites

Install SAP Power Monitor:

1. Visit the SAP Power Monitor releases page
2. Download the latest .pkg file
3. Install the downloaded file

Install Homebrew

1. Visit the Homebrew page
2. Copy the installation command and run it in your terminal

Automatic Installation (Recommended)

1. Clone the repository:

git clone git@github.com:rewse/power-monitor-mqtt.git
cd power-monitor-mqtt

2. Install dependencies: This will install mosquitto and jq.

make deps

3. Install the script: The script will be installed to ~/.local/bin and configuration files to ~/.config/power-monitor-mqtt.

make install

4. Edit the configuration file:

vim ~/.config/power-monitor-mqtt/config

Makefile Commands

Available Makefile commands:

make help         # Show help message
make deps         # Install dependencies (mosquitto, jq)
make install      # Install script and config file
make test         # Run script in test mode
make clean        # Remove config file
make uninstall    # Remove installed script

Manual Installation

Note: Make sure you have completed the Prerequisites section above before proceeding.

1. Clone the repository:

git clone git@github.com:rewse/power-monitor-mqtt.git
cd power-monitor-mqtt

2. Install dependencies manually:

brew install mosquitto jq

3. Create configuration file:

mkdir -p ~/.config/power-monitor-mqtt
cp config.example ~/.config/power-monitor-mqtt/config

4. Edit the configuration file:

vim ~/.config/power-monitor-mqtt/config

Configuration

Configure the following items in the configuration file (~/.config/power-monitor-mqtt/config):

• MQTT_HOST: MQTT broker hostname
• MQTT_PORT: MQTT broker port (default: 1883)
• MQTT_USERNAME: MQTT authentication username (default: pub_client)
• MQTT_PASSWORD: MQTT authentication password
• TOPIC_PREFIX: MQTT topic prefix (default: power-monitor)
• DEVICE_NAME: Device name (default: Mac's hostname)
• INTERVAL: Data transmission interval for continuous mode (default: 60 seconds)

Usage

Test Mode

Retrieves data from SAP Power Monitor only, without sending to MQTT broker.

./power-monitor-mqtt.sh --test

Single Run

Sends power value to MQTT broker once. Use with helper tool like Keyboard Maestro, LaunchAgent, or cron for periodic execution.

./power-monitor-mqtt.sh --once

Continuous Mode

Runs persistently at INTERVAL intervals.

./power-monitor-mqtt.sh

Show Configuration

./power-monitor-mqtt.sh --config

MQTT Topics

The script publishes data to the following topics:

• {TOPIC_PREFIX}/{DEVICE_NAME}/power/current - Power value (W)
• {TOPIC_PREFIX}/{DEVICE_NAME}/power/average - Average power value (W)
• {TOPIC_PREFIX}/{DEVICE_NAME}/status - Status information

Data Format

Power value (current / average)

{
  "value": 45.2,
  "unit": "W",
  "timestamp": "2024-12-16T16:30:00+09:00"
}

Status Information

{
  "measurements": 150,
  "country_code": "unknown",
  "precise_location": false,
  "carbon_footprint": -1,
  "timestamp": "2024-12-16T16:30:00+09:00"
}

Note: As of now, country_code, precise_location, and carbon_footprint do not return correct values from SAP Power Monitor.

Log Viewing

Logs are written to ~/Library/Logs/power-monitor-mqtt/power-monitor-mqtt.log by default. The log file is automatically rotated when it reaches the maximum size.

Periodic Execution Setup Example

Using Keyboard Maestro

Import Pre-configured Macro

1. Download Execute-power-monitor-mqtt.kmmacros
2. Open Keyboard Maestro
3. Import the macro:
   • Go to File > Import > Import Macros Safely...
   • Select the downloaded .kmmacros file
4. Review and adjust the interval if needed

Manual Setup

1. Open Keyboard Maestro
2. Create a new macro with a descriptive name (e.g., "Execute power-monitor-mqtt")
3. Set the trigger:
   • Type: "Periodically while logged in"
   • Interval: "Repeating every 1 Minutes" (adjust as needed)
4. Add an action:
   • Type: "Execute a Shell Script"
   • Script content: PATH=/opt/homebrew/bin:$PATH ~/.local/bin/power-monitor-mqtt.sh --once
5. Save the macro

Note: The PATH environment variable must include /opt/homebrew/bin (or /usr/local/bin for Intel Macs) to ensure mosquitto_pub and jq commands are accessible.

Home Assistant Integration

Example configuration for Home Assistant:

MQTT Sensor Configuration

mqtt:
  sensor:
    - name: "My Mac Power Current"
      state_topic: "power-monitor/my-mac/power/current"
      value_template: "{{ value_json.value }}"
      unit_of_measurement: "W"
      device_class: power
      
    - name: "My Mac Power Average"
      state_topic: "power-monitor/my-mac/power/average"
      value_template: "{{ value_json.value }}"
      unit_of_measurement: "W"
      device_class: power

Power Measurement Accuracy Note

Important: The power values reported by macOS internal sensors are typically 15-25% lower than actual AC power consumption measured by external devices (smart plugs, power meters). This difference is due to:

• AC-DC conversion efficiency: Power adapter losses (10-20%)
• Internal power conversion: Motherboard and component efficiency losses
• Measurement scope: Internal sensors may not account for all components and external devices
• Measurement methodology: Internal values are often estimates based on component usage

For more accurate power consumption calculations (e.g., electricity cost estimation), consider using a correction factor.

Corrected Power Sensor (20% Increase)

template:
  - sensor:
      - name: "My Mac Power Current Corrected"
        unit_of_measurement: "W"
        device_class: power
        state: "{{ (states('sensor.my_mac_power_current') | float(0) * 1.2) }}"
        
      - name: "My Mac Power Average Corrected"
        unit_of_measurement: "W"
        device_class: power
        state: "{{ (states('sensor.my_mac_power_average') | float(0) * 1.2) }}"

Power Consumption (kWh) Calculation with Integral Sensor

sensor:
  # Using raw internal sensor values
  - platform: integration
    source: sensor.my_mac_power_current
    name: My Mac Energy Total Internal
    unit_prefix: k
    round: 6
    method: trapezoidal
    max_sub_interval:
      minutes: 5
      
  # Using corrected values for more accurate consumption
  - platform: integration
    source: sensor.my_mac_power_current_corrected
    name: My Mac Energy Total Corrected
    unit_prefix: k
    round: 6
    method: trapezoidal
    max_sub_interval:
      minutes: 5