My approach to detailed energy management in Home Assistant
I started measuring my home energy use about 3 years ago. In the beginning it was just interesting to get things setup and see my total usage. It gave me some insights, but I found myself wanting a more granular level of detail that would allow me to more quickly identify problem areas and opportunities for improvement.
Detailed energy monitoring with Emporia Gen2 Vue
About 18 months ago I purchased two Emporia Gen2 Vue devices and outfitted 16 circuits in each of my two electrical panels. Being able to report on the total power usage as well as details of 32 selected circuits gives a really nice level of detail.
I purchased the Vue2 devices because of the well thought out design, attractive pricing, and at that time, Emporia was saying local API was on their roadmap… based on many inquiries and Emporia’s forum responses, it doesn’t seem like that will ever happen.
Using Emporia’s cloud services
Until a week ago, I had been using the custom_component integration that was written by magico13. That served me well, but it requires cloud accounts is limited to 1 minute reporting because of load on cloud servers. One minute reporting is still very good, and probably covers 98% of the use cases that anyone would have.
Emporia Gen2 Vue running ESPHome!
Even though everything was working, I always felt a little cheated that I couldn’t access the full capabilities of the device in Home Assistant. Last week I stumbled across this fantastic project where a group reverse engineered the Vue device and provided instructions to flash with ESPHome! I flashed both units later that day, and after a few small hurdles, I had everything working perfectly. I finally have this unit working exactly as I originally anticipated with the ability to see real-time data with updates few seconds.
Home Assistant Energy Dashboard
The Home Assistant developers have done a great job adding in better support for monitoring energy. Nice looking dashboards with improved statistics and reporting capabilities. All the work I’ve done can also take advantage of those built in features. I’d like to see native capabilities to more easily group devices together for energy reporting and show real time power reporting as I’ve done in mine, but I’m guessing it will come at some point. For my HA energy dashboard, I’m only monitoring my device groups, not individual devices since I have that in my custom dashboard. I also have more detailed reporting in Influx/Grafana, but that’s a separate discussion.
General concepts for my approach
I’ll start out by saying that not everyone will agree with everything I do in my approach toward this. (i.e. basing a lot of this on entity_id naming and not aiming for “Perfect” measurements of energy usage) That said, there are always limitations and compromises to consider, and based on a good amount of research, trial, and error, I think this is a pretty good compromise. It definitely gives me a clear and detailed understanding of my usage.
Here are the key points in my configuration:
- I only store and report data from power and energy sensors that I’ve created with templates. This allows to ensure consistent naming and attributes since I use power details from many different integrations and sensors. This also allows me to create a relationship between the circuit being monitored and the loads that are running on that circuit. Naming is also very important when you want to use things like filters or templates to minimize the amount of manual group management required.
- Similar to the point above, you should consider excluding unused power and energy sensors from the recorder to minimize data size and performance impact.
- I keep all of my energy configuration in single package yaml file for easy management. If you aren’t using the package directory approach for managing and organizing at least your complex configurations, you should look into it.
Backend Configuration:
Create an input_number to store your energy cost
You can also reference this entity in the native energy dashboard, so it is dual purpose. Note I do not have variable energy rates, but @guardmedia wrote a nice addition to this thread with a detailed variable rate configuration here.
input_number:
energy_kwh_cost:
name: Energy kWh Cost
icon: mdi:currency-usd
mode: box
unit_of_measurement: "USD/kWh"
min: 0.001
max: 1
Create a template trigger for all energy sensors
The reason for the trigger template for sensors is to control the number of updates that would occur otherwise. In my case I’m having the templates evaluate and capture energy data from all sensors and groups every 5 seconds. So my trigger is a 5 second pattern. You can change that to your needs, but your database will grow very quickly and performance will suffer if you aren’t careful.
IMPORTANT: If you use a regular template sensor without a trigger for a group of devices, you will likely have issues. Consider a group with 10 devices getting updates every 1 second. That template will re-evaluate every time each one of those devices reports. That’s at least 10+ updates per second for each group sensor which over days and weeks will add up to issues.
template:
- trigger:
# NOTE - This approach does somewhat impact the accuracy of your data since it is not averaging the data in
# between the time periods, but it will still end up being relatively close and give you a good data
# about energy usage
- platform: time_pattern
seconds: "/5" #Only pull electric data every 5 seconds to minimize data / performance impact
- platform: homeassistant
event: start
- platform: event
event_type: "call_service"
event_data:
domain: "template"
service: "reload"
sensor:
################ Electrical Panel #1 Voltage ###############
- name: electric_home_voltage
attributes:
tmp_friendly_name: "Electric Home Voltage"
<<: &voltage_sensor_force_update
min_last_updated: "{{ now().minute }}" #Forces reporting every 1 min
<<: &voltage_sensor_defaults
device_class: voltage
unit_of_measurement: "V"
state_class: measurement
state: "{{ (states('sensor.electric_p1_phase_a_voltage') | float(0) + states('sensor.electric_p1_phase_b_voltage') | float(0)) | round(1) }}"
- name: electric_home_l1_voltage
attributes:
tmp_friendly_name: "Electric Home Leg 1 Voltage"
<<: *voltage_sensor_force_update
<<: *voltage_sensor_defaults
state: "{{ (states('sensor.electric_p1_phase_a_voltage') | float(0)) | round(1) }}"
- name: electric_home_l2_voltage
attributes:
tmp_friendly_name: "Electric Home Leg 2 Voltage"
<<: *voltage_sensor_force_update
<<: *voltage_sensor_defaults
state: "{{ (states('sensor.electric_p1_phase_b_voltage') | float(0)) | round(1) }}"
################ Electrical Whole Home Power ###############
- name: electric_home_total_power
attributes:
tmp_friendly_name: "Electric Home Total Power"
<<: &power_sensor_force_update
two_min_update: "{% if now().minute is divisibleby(2) %} {{now().minute}} {% else %} {{now().minute - 1 }} {% endif %}" #Ensure updates occur at least every 2 min for influx reporting
state: "{{ (states('sensor.p1_00_total_power') | float(0) + states('sensor.p2_00_total_power') | float(0)) | round(1) }}"
<<: &power_sensor_defaults
device_class: power
unit_of_measurement: "W"
state_class: measurement
################ Electrical Panel #1 Power ###############
# Note - Subtracting out power in the templates is not perfect. The circuits get updated every x seconds from Emporia vue, but the change to the virtual circuits happens immediately.
# Currently handling by simply not allowing the total power of the circuit to go negative which is why max() filter is in use. (i.e. 0 is bigger than negative so max will return that)
- name: p1_00_total_power
attributes:
tmp_friendly_name: "Electric Panel 1 Total Power"
<<: *power_sensor_force_update
state: "{{ max( states('sensor.electric_p1_total_power') | float(0) | round(1), 0.0 ) }}"
<<: *power_sensor_defaults
- name: p1_01_first_floor_hvac_ahu_1_power
attributes:
tmp_friendly_name: "First Floor HVAC AHU 1 Power"
<<: *power_sensor_force_update
state: "{{ max( states('sensor.fl1_air_handler_p1_1_power') | float(0) | round(1), 0.0 ) }}"
<<: *power_sensor_defaults
- name: p1_02_first_floor_hvac_ahu_2_power
attributes:
tmp_friendly_name: "First Floor HVAC AHU 2 Power"
<<: *power_sensor_force_update
state: "{{ max( states('sensor.fl1_air_handler_p1_2_power') | float(0) | round(1), 0.0 ) }}"
<<: *power_sensor_defaults
- name: p1_03_kitchen_gfci_power
attributes:
tmp_friendly_name: "Kitchen GFCI Power"
<<: *power_sensor_force_update
state: "{{ max( states('sensor.kitchen_gfci_p1_3_power') | float(0) | round(1), 0.0 ) }}"
<<: *power_sensor_defaults
- name: p1_04_office_power
attributes:
tmp_friendly_name: "Office Power"
<<: *power_sensor_force_update
state: >-
{% set virtualpower = expand('group.p1_04_v_power') | rejectattr('state', 'in', ['unavailable', 'unknown']) | map(attribute='state') | map('float') | sum | round(2) %}
{{ max( (states('sensor.office_p1_4_power') | float(0) - virtualpower) | round(1), 0.0 ) }}
<<: *power_sensor_defaults
- name: p1_04_v_office_floor_light_power
attributes:
tmp_friendly_name: "Office Floor Light Power"
<<: *power_sensor_force_update
state: "{{ max( (5 * 8 * state_attr('light.office_floor_light','brightness') | float(0) / 255) | round(1), 0.0 ) }}"
<<: *power_sensor_defaults
- name: p1_04_v_office_computer_outlet_power
attributes:
tmp_friendly_name: "Office Computer Outlet Power"
<<: *power_sensor_force_update
state: "{{ max( states('sensor.office_computer_outlet_power') | float(0) | round(1), 0.0 ) }}"
<<: *power_sensor_defaults
- name: p1_05_kitchen_refrigerator_power
attributes:
tmp_friendly_name: "Kitchen Refrigerator Power"
<<: *power_sensor_force_update
state: "{{ max( states('sensor.kitchen_refrigerator_p1_5_power') | float(0) | round(1), 0.0 ) }}"
<<: *power_sensor_defaults
<<<<<<<<<<<<<<<<<<<<<<<<<< Truncated >>>>>>>>>>>>>>>>>>>>>>>>>>>
In the snip of yaml above, it probably looks a little complex, but take a look at each entry and it gets a little easier. A few key points:
- I am using yaml anchors to simplify, thats why you see the “<<: &” and “<<: *”. It’s like declaring a variable, then allows use of those items throughout your code.
- The names are structured and specific. In the case of p1_00_total_power, that is the total power being delivered by electric panel 1, while p1_04_office_power is electric panel 1, the 4th monitored circuit.
- Take note of the next entry which is p1_04_v_office_floor_light_power. The “v” is meant to stand for virtual, which means it will be used for some calculations on that circuit. This naming structure allows easy automated creation of “circuit groups” that make up the known loads on each circuit. By subtracting the known loads from the circuit, you are left with the remaining power so nothing is double counted in reporting totals.
- The last part of the naming used for each sensor is also very specific. “_power”, “_total_power”, “_group_total_power”, “_energy”, “_group_total_energy”, “_group_daily_total_energy”, “_group_monthly_total_energy”, “_group_daily_total_energy_cost”, “_group_monthly_total_energy_cost”
- The use of “max( x, 0.0)” in most of the states is an easy way of preventing negative power readings which are typically noise or could also occur briefly due to the way calculations are being done
Calculating the values the power sensors templates
Notice there are several ways to get power usage:
- Direct from another power sensor:
{{ max( states('sensor.fl1_air_handler_p1_1_power') | float(0) | round(1), 0.0 ) }}
- Adding sensors together:
{{ (states('sensor.electric_p1_phase_a_voltage') | float(0) + states('sensor.electric_p1_phase_b_voltage') | float(0)) | round(1) }}
- You don’t need to have true energy monitoring on devices to track power usage. If you can determine whether the device is on or off, and you can estimate is power while on, then just calculate it in a template. Granted it is an estimate, but if can give you a lot more information if you are OK with the compromise. Use the p1_04_v_office_floor_light_power example again. That template is calculating an energy value estimate based on 5 bulbs x 8 watts each x brightness of the light to determine power usage.
{{ (5 * 8 * state_attr('light.office_floor_light','brightness') | float(0) / 255) | round(1) }}
- Same as above, but when only on / off are known for a 45W device:
{% if is_state('switch.landscape_lighting','on') %}{{ 45| float(0) | round(1)}}{% else %}{{ 0 | float(0) | round(1) }}{% endif %}
- More complex calculations can also be done using templates and groups. In the case of p1_04_office_power, that is a monitored circuit with multiple loads. The known loads are listed with the “v” designations so they can be automatically placed into groups to be subtracted from that circuit. With this approach, the value of p1_04_office_power ends up only being the remaining power of the circuit after the known loads are removed. Without calculation the p1_04_office_power circuit would be 77.4W, which would be double counting the loads on that circuit that are also being measured.
- name: p1_04_office_power
attributes:
tmp_friendly_name: "Office Power"
<<: *power_sensor_force_update
state: >-
{% set virtualpower = expand('group.p1_04_v_power') | rejectattr('state', 'in', ['unavailable', 'unknown']) | map(attribute='state') | map('float') | sum | round(2) %}
{{ max( (states('sensor.office_p1_4_power') | float(0) - virtualpower) | round(1), 0.0 ) }}
<<: *power_sensor_defaults
Creating power sensors for devices in a group
In this example, the template will expand out group.water_heater_group_total_power and add the power usage of all the sensors in that group. The resulting sensor created will be sensor.water_heater_group_total_power. Note the different entities even group name is the same as the sensor name, that is just for easy management. In the example picture, this sensor would just be the “head” entry total for kitchen appliances, the sum of all the values in the group shown.
IMPORTANT: This should be done in a trigger template, otherwise will constantly be recalculating. See warnings above.
- name: kitchen_appliance_group_total_power
icon: mdi:fridge-outline
state: >-
{% set virtualpower = expand('group.kitchen_appliance_group_total_power') | rejectattr('state', 'in', ['unavailable', 'unknown']) | map(attribute='state') | map('float') | sum | round(2) %}
{{ max( virtualpower | round(1), 0.0 ) }}
attributes:
tmp_friendly_name: "Kitchen Appliance Group Total Power"
<<: *power_sensor_force_update
<<: *power_sensor_defaults
Creating groups of power sensors
One option is to just manually create the groups you want to monitor, then use the formulas found above to calculate total power usage of that group of sensors. I wanted to automate that group creation and maintenance based on entity names. It does take a good naming structure for it to work properly, but if you stick to the structure it works well.
automation:
################ Create and update power groupings for circuits and devices ###############
- alias: "Update Power Groups"
trigger:
- platform: homeassistant
event: start
- platform: event
event_type: "call_service"
event_data:
domain: "group"
service: "reload"
action:
- service: group.set
data_template:
object_id: p1_04_v_power
entities: >
{% set ns = namespace(entities=[]) %}
{% for s in states.sensor if s.object_id.startswith('p1_04_v') and s.object_id.endswith('_power') %}
{% set ns.entities = ns.entities + [ s.entity_id ] %}
{% endfor %}
{{ ns.entities }}
- service: group.set
data_template:
object_id: kitchen_appliance_group_total_power
entities: >
{% set ns = namespace(entities=[]) %}
{% for s in states.sensor if '_kitchen_' in s.object_id and not '_light_' in s.object_id and (s.object_id.startswith('p1_') or s.object_id.startswith('p2_')) and s.object_id.endswith('_power') %}
{% set ns.entities = ns.entities + [ s.entity_id ] %}
{% endfor %}
{{ ns.entities }}
Simplifying the energy calculations
When looking into this, I remember it was really tricky to figure out what I needed to do in Home Assistant to convert from power to energy. It is important to be clear on these two terms, they aren’t directly interchangeable.
Power rate of producing or consuming energy. For home electric normally measured in watts(W) or kilowatts(kW). Note I keep everything in watts for simiplicity
Energy measures the total quantity of “Work” done. For home electric normally measured in kWh (kiloWatt hours).
If you are measuring your power in Watts, you can easily track your energy/kWh by following the patterns in the following 3 sections.
Create sensors for hourly energy calculations
These sensors continuously calculate the kWh over the past hour which allows the utility meter integration to capture the daily and monthly energy consumption from this data.
sensor:
################ Total hourly energy calculation ###############
- platform: integration
name: electric_home_total_energy
source: sensor.electric_home_total_power
<<: &energy_calculation_defaults
unit_time: h
unit_prefix: k
round: 2
- platform: integration
name: kitchen_appliance_group_total_energy
source: sensor.kitchen_appliance_group_total_power
<<: *energy_calculation_defaults
Tracking consumption with the utility_meter
These sensors are what will be used for actual reporting of usage per day or per month in kWh
utility_meter:
################ Track daily consumption for each grouping ###############
electric_home_daily_total_energy:
source: sensor.electric_home_total_energy
cycle: daily
kitchen_appliance_group_daily_total_energy:
source: sensor.kitchen_appliance_group_total_energy
cycle: daily
################ Track monthly consumption for each grouping ###############
electric_home_monthly_total_energy:
source: sensor.electric_home_total_energy
cycle: monthly
kitchen_appliance_group_monthly_total_energy:
source: sensor.kitchen_appliance_group_total_energy
cycle: monthly
Calculating Cost
sensor:
- platform: template
sensors:
################ Calculate daily energy cost for each grouping ###############
electric_home_daily_total_energy_cost:
friendly_name: "Electric Home Daily Total Energy Cost"
value_template: >-
{{ max( (states('sensor.electric_home_daily_total_energy') | float(0) * states('input_number.energy_kwh_cost') | float(0)) | round(2), 0.00 ) }}
<<: &energy_cost_defaults
unit_of_measurement: "$"
icon_template: mdi:currency-usd
kitchen_appliance_group_daily_total_energy_cost:
friendly_name: "Kitchen Appliance Group Daily Total Energy Cost"
value_template: >-
{{ max( (states('sensor.kitchen_appliance_group_daily_total_energy') | float(0) * states('input_number.energy_kwh_cost') | float(0)) | round(2), 0.00 ) }}
<<: *energy_cost_defaults
################ Calculate monthly energy cost for each grouping ###############
electric_home_monthly_total_energy_cost:
friendly_name: "Electric Home Monthly Total Energy Cost"
value_template: >-
{{ max( (states('sensor.electric_home_monthly_total_energy') | float(0) * states('input_number.energy_kwh_cost') | float(0)) | round(2), 0.00 ) }}
<<: *energy_cost_defaults
kitchen_appliance_group_monthly_total_energy_cost:
friendly_name: "Kitchen Appliance Group Monthly Total Energy Cost"
value_template: >-
{{ max( (states('sensor.kitchen_appliance_group_monthly_total_energy') | float(0) * states('input_number.energy_kwh_cost') | float(0)) | round(2), 0.00 ) }}
<<: *energy_cost_defaults
Example of all entities created for one energy group type
Bringing it all together in the UI
Last year, around earth day, I decided it would be a good time to update my dashboards with a focus on energy throughout. Each one of my dashboard pages has energy details at the top to keep it visible and top of mind. Here are some examples:
title: "" ######################### Home #########################
icon: mdi:home
cards:
- type: vertical-stack
cards:
- type: entities
title: "Home"
icon: mdi:home
show_header_toggle: false
entities:
- type: section
- entity: sensor.electric_home_daily_total_energy_cost
type: custom:multiple-entity-row
name: Energy
icon: mdi:flash-outline
state_header: Today $
format: precision2
secondary_info: false
unit: false
styles:
font-weight: bold
color: green
width: 34px
entities:
- entity: sensor.electric_home_monthly_total_energy
name: Month kWh
format: precision0
unit: false
styles:
width: 34px
- entity: sensor.electric_home_monthly_total_energy_cost
name: Month $
format: precision2
unit: false
styles:
color: green
width: 34px
- entity: sensor.electric_home_daily_total_energy
name: Today kWh
format: precision1
unit: false
styles:
width: 34px
- entity: sensor.count_outside_fans_on
type: custom:multiple-entity-row
name: "On"
icon: mdi:lightbulb-group
state_header: Out Fans
format: precision0
secondary_info: false
unit: false
entities:
- entity: sensor.count_inside_lights_on
name: In Lights
format: precision0
unit: false
- entity: sensor.count_inside_fans_on
name: In Fans
format: precision0
unit: false
- entity: sensor.count_outside_lights_on
name: Out Lights
format: precision0
unit: false
- entity: sensor.count_doors_open
type: custom:multiple-entity-row
name: "Security"
icon: mdi:shield
state_header: ""
format: precision0
secondary_info: false
unit: false
show_state: false
entities:
- entity: sensor.count_garage_doors_open
name: "Garage Open"
format: precision0
unit: false
- entity: sensor.count_doors_open
name: "Doors Open"
format: precision0
unit: false
title: "" ######################### Lights #########################
icon: mdi:lightbulb-multiple
cards:
## Heating and cooling
- type: entities
title: "Lighting"
icon: mdi:lightbulb-group
show_header_toggle: false
entities:
- type: section
- entity: sensor.light_group_daily_total_energy_cost
type: custom:multiple-entity-row
name: Energy
icon: mdi:flash-outline
state_header: Today $
format: precision2
secondary_info: false
unit: false
styles:
font-weight: bold
text-align: right
color: green
entities:
- entity: sensor.light_group_monthly_total_energy
name: Month kWh
format: precision1
unit: false
- entity: sensor.light_group_monthly_total_energy_cost
name: Month $
format: precision2
unit: false
styles:
font-weight: bold
text-align: right
color: green
- entity: sensor.light_group_daily_total_energy
name: Today kWh
format: precision1
unit: false
- type: custom:fold-entity-row
head:
entity: sensor.light_group_total_power
name: "Power"
icon: " "
entities:
- type: custom:auto-entities
show_empty: false
card:
type: entities
title: ""
show_header_toggle: false
sort:
method: state
reverse: true
numeric: true
filter:
include:
- group: "group.light_group_total_power"
- type: section
- entity: sensor.count_outside_fans_on
type: custom:multiple-entity-row
name: "On"
icon: mdi:lightbulb-group
state_header: Out Fans
format: precision0
secondary_info: false
unit: false
entities:
- entity: sensor.count_inside_lights_on
name: In Lights
format: precision0
unit: false
- entity: sensor.count_inside_fans_on
name: In Fans
format: precision0
unit: false
- entity: sensor.count_outside_lights_on
name: Out Lights
format: precision0
unit: false
title: "" ######################### Home Tech Net#########################
icon: "mdi:network"
badges: []
cards:
- type: entities
title: "Technology"
icon: mdi:network
show_header_toggle: false
entities:
- type: section
- entity: sensor.technology_group_daily_total_energy_cost
type: custom:multiple-entity-row
name: Energy
icon: mdi:flash-outline
state_header: Today $
format: precision2
secondary_info: false
unit: false
styles:
font-weight: bold
color: green
width: 34px
entities:
- entity: sensor.technology_group_monthly_total_energy
name: Month kWh
format: precision1
unit: false
styles:
width: 34px
- entity: sensor.technology_group_monthly_total_energy_cost
name: Month $
format: precision2
unit: false
styles:
color: green
width: 34px
- entity: sensor.technology_group_daily_total_energy
name: Today kWh
format: precision1
unit: false
styles:
width: 34px
- type: custom:fold-entity-row
head:
entity: sensor.technology_group_total_power
name: "Power"
icon: " "
entities:
- type: custom:auto-entities
show_empty: false
card:
type: entities
title: ""
show_header_toggle: false
sort:
method: state
reverse: true
numeric: true
filter:
include:
- group: "group.technology_group_total_power"
- type: custom:fold-entity-row
head:
type: section
label: Configure
open: false
entities:
- entity: input_boolean.network_device_down_notify
- entity: input_boolean.server_device_down_notify
- entity: input_boolean.wan_down_notify
- entity: input_boolean.device_restart_notify
Extra credit
Once you have access to all of your power and energy data, there are many creative things you can use it for.
Laundry
- See when appliances are running
- Get notifications when a cycle is finished
- Count how many times each appliance has run in the past 7 days
Water
- See how long your water heater is running each day
- Count how many times per hour your sump pump is running
- Notify if your sump pump runs x times per hour
Heating and Cooling
- Calculate the amount of time your heater is running per day
- For those with heat pumps, count your defrost cycles per day as well as aux heat runtime.
