***NOTE: This page will be a work in progress.

It took many months to find the time and piece all the necessary components together in order to get these 3 variables plotted together on a chart. The only one missing now is solar power generation.

Tech.

  • esp32 hardware
  • mcp2515 canbus receiver
  • can bus
  • raspberry pi
  • home assistant
  • esphome
  • influxdb

The dot point version of how this works.

  • motor controller for the EV motor has a canbus output. this has a HUGE number of data points that are available from rpm/torque/temperature etc. the canbus from the controller goes into an mcp2515 connected to an esp32. esp32 uses esphome, which sends rpm and kwh data to home assistant, which stores data in influxdb
  • mariana ais/gps has a serial connection that goes into a raspberry pi. signal k has a data connection for the GPS info. the emarine MQTT plugin for signal k sends this GPS(speed over ground) info to the mqtt broker which is subscribed to by the home assistant. once in home assistant it gets stored in the influxdb.

Influxdb is where the visual magic happens. This is a specialized db for time sequence data. Each data point that home assistant sends into the influx db has a number of fields but most importantly a unique id, time period and a value. This makes it simpler to make time-based charts to correlate data visually as in the image above.

The next step in this will be to add in the power generation from the solar panels. Home assistant currently reads from the INDININI Victron solar charge controllers for the house battery, BUT is not able to do so from the solar charge controller of the motor battery. This means a shunt needs to be added inline on the solar charge controller for the motor battery that has the capability to output readings for the power that is being generated. Once this is done, a 4th variable will be added to this chart. That will allow a visual representation of how fast to go to ONLY use the power that is generated from the sun.

At the moment we can see the watts that are being made from a small LCD screen on the charge controller. On a summer mid day, we can make 1300 watts from the 1600 watts of panels. The goal will be to install at least 4kw of panels with a target to generate 3.5kw of power to enable longer motoring on a summer day.