Many friends have been curious about the returns from my photovoltaic (PV) investment, often asking about the financial benefits it has brought. While it’s straightforward to mention the earnings from the energy sold back to the grid, a significant portion of the value actually comes from the solar energy I utilize directly. By consuming the energy produced by my PV system, I save on electricity costs, including the network tariffs, which is a considerable advantage.
To thoroughly understand and communicate the total benefits of my PV system, I’ve developed an Apex chart dashboard. This tool goes beyond just tracking energy sold; it provides a comprehensive overview of the entire PV system’s performance, including the cost savings from using solar energy directly. This holistic approach allows me to quantify and visualize the true value of my investment, encompassing both the energy exported to the grid and the savings from reduced reliance on external power sources.
Probably took too complex route, but got the result. As i have 3phase system and in Estonia our grid will count every phase separately, meaning that if i export 1kw and 1kw on 2 phases and import 2kw on 1 phase, I still have to pay the tariff on the 2kw. It’s quite unique approach in our country. Usually grid will sum phases.
What you need:
- Inverter production power (in my case power for each phase). My huawei is not giving this information and i needed to calculate it from the phases currents:
- platform: template
sensors:
inverter_phase_1_power:
friendly_name: "Inverter Phase 1 Power"
unit_of_measurement: "W"
value_template: >-
{{ (states('sensor.inverter_phase_a_current') | float *
states('sensor.inverter_phase_a_voltage') | float *
states('sensor.inverter_power_factor') | float) }}
- platform: template
sensors:
inverter_phase_2_power:
friendly_name: "Inverter Phase 2 Power"
unit_of_measurement: "W"
value_template: >-
{{ (states('sensor.inverter_phase_b_current') | float *
states('sensor.inverter_phase_b_voltage') | float *
states('sensor.inverter_power_factor') | float) }}
- platform: template
sensors:
inverter_phase_3_power:
friendly_name: "Inverter Phase 3 Power"
unit_of_measurement: "W"
value_template: >-
{{ (states('sensor.inverter_phase_c_current') | float *
states('sensor.inverter_phase_c_voltage') | float *
states('sensor.inverter_power_factor') | float) }}
- Power back to grid. I have Shelly EM3 and it gives a power entities for each phase. Negative result means power is going back to grid. I made template sensor that will show value when it’s negative and show it as as a positive number (Note: absolute value would be better than -1)
- platform: template
sensors:
phase_1_power_back_to_grid:
friendly_name: "Phase 1 Power Back to Grid"
unit_of_measurement: "W"
value_template: >-
{% set power = states('sensor.phase_1_power') | float %}
{{ [0, power * -1] | max }}
phase_2_power_back_to_grid:
friendly_name: "Phase 2 Power Back to Grid"
unit_of_measurement: "W"
value_template: >-
{% set power = states('sensor.phase_2_power') | float %}
{{ [0, power * -1] | max }}
phase_3_power_back_to_grid:
friendly_name: "Phase 3 Power Back to Grid"
unit_of_measurement: "W"
value_template: >-
{% set power = states('sensor.phase_3_power') | float %}
{{ [0, power * -1] | max }}
- Total back to grid power
- platform: template
sensors:
total_power_back_to_grid:
friendly_name: "Total Power Back to Grid"
unit_of_measurement: "W"
value_template: >
{{ states('sensor.phase_1_power_back_to_grid') | float
+ states('sensor.phase_2_power_back_to_grid') | float
+ states('sensor.phase_3_power_back_to_grid') | float }}
- Total own used PV power
- platform: template
sensors:
pv_own_usage_total_power:
friendly_name: "Total PV Own Usage Power"
unit_of_measurement: "W"
value_template: >
{% set phase_1_power = states('sensor.inverter_phase_1_power') | float %}
{% set phase_1_back_to_grid = states('sensor.phase_1_power_back_to_grid') | float %}
{% set phase_2_power = states('sensor.inverter_phase_2_power') | float %}
{% set phase_2_back_to_grid = states('sensor.phase_2_power_back_to_grid') | float %}
{% set phase_3_power = states('sensor.inverter_phase_3_power') | float %}
{% set phase_3_back_to_grid = states('sensor.phase_3_power_back_to_grid') | float %}
{{ (phase_1_power - phase_1_back_to_grid) + (phase_2_power - phase_2_back_to_grid) + (phase_3_power - phase_3_back_to_grid)| round(2) }}
- Current benefit calculations. Needed for the Utility meter step to start counting. Back to grid I use Nordpool price without VAT. Own usage I use nordpool with VAT + networks tariffs.
- platform: template
sensors:
pv_to_grid_benefit_now:
friendly_name: 'PV to grid now'
unit_of_measurement: "EUR"
value_template: "{{ states('sensor.nordpool_kwh_ee_eur_3_10_0') | float * states('sensor.total_power_back_to_grid') | float / 1000 }}"
- platform: template
sensors:
pv_own_usage_benefit_now:
friendly_name: 'PV Own Usage Now'
unit_of_measurement: "EUR"
value_template: "{{ states('sensor.total_el_price') | float * states('sensor.pv_own_usage_total_power') | float / 1000 }}"
- Make Reiman Sum helpers to calculate cumulative benefit from the current benefit entities from last step. Settings > Devices & Services > Helpers > Create Helper > Integration - Reiman sum integral sensor
1.
Name: PV Own Usage Benefit Cumulative
Input Sensor: sensor.pv_own_usage_benefit_now
Integration method: Left
Precicion: 2
Time Unit: hours
2.
Name: PV to grid cumulative Benefit
Input Sensor: sensor.pv_to_grid_benefit_now
Integration method: Left
Precicion: 2
Time Unit: hours
- (optional) Template sensor that will sum the cumulative own use and back to gid together
- platform: template
sensors:
total_pv_all_time_benefit:
friendly_name: "Total PV All Time Benefit"
unit_of_measurement: '€'
value_template: >
{% set pv_own_usage = states('sensor.pv_own_usage_benefit_cumulative') %}
{% set pv_to_grid = states('sensor.pv_to_grid_cumulative_benefit') %}
{% set pv_own_value = 0 if pv_own_usage == "unknown" else pv_own_usage | float %}
{% set pv_to_grid_value = 0 if pv_to_grid == "unknown" else pv_to_grid | float %}
{{ (pv_own_value + pv_to_grid_value) | round(2) }}
- So now we have entities that will cumulative current own usage and back to grid benefits. Next step is to make utility meters. You can do it in UI, but i preferres configuration.yaml, as there are quite a few of them (daily, monthly, yearly or all time if you want). Daily and Monthly are needed in my setup to show the apex chart corectly.
utility_meter:
pv_own_usage_benefit_daily:
source: sensor.pv_own_usage_benefit_cumulative
name: PV Own Usage Benefit Daily
cycle: daily
pv_to_grid_benefit_daily:
source: sensor.pv_to_grid_cumulative_benefit
name: PV to Grid Benefit Daily
cycle: daily
pv_own_usage_benefit_monthly:
source: sensor.pv_own_usage_benefit_cumulative
name: PV Own Usage Benefit Monthly
cycle: monthly
pv_to_grid_benefit_monthly:
source: sensor.pv_to_grid_cumulative_benefit
name: PV to Grid Benefit Monthly
cycle: monthly
pv_own_usage_benefit_yearly:
source: sensor.pv_own_usage_benefit_cumulative
name: PV Own Usage Benefit Yearly
cycle: yearly
pv_to_grid_benefit_yearly:
source: sensor.pv_to_grid_cumulative_benefit
name: PV to Grid Benefit Yearly
cycle: yearly
- Template to calculate the totals of daily, monthly and yearly benefits
- platform: template
sensors:
total_pv_daily_benefit:
friendly_name: "Total PV Daily Benefit"
unit_of_measurement: '€'
value_template: >
{% set pv_own_usage = states('sensor.pv_own_usage_benefit_daily') %}
{% set pv_to_grid = states('sensor.pv_to_grid_benefit_daily') %}
{% set pv_own_value = 0 if pv_own_usage == "unknown" else pv_own_usage | float %}
{% set pv_to_grid_value = 0 if pv_to_grid == "unknown" else pv_to_grid | float %}
{{ (pv_own_value + pv_to_grid_value) | round(2) }}
- platform: template
sensors:
total_pv_monthly_benefit:
friendly_name: "Total PV Monthly Benefit"
unit_of_measurement: '€'
value_template: >
{% set pv_own_usage = states('sensor.pv_own_usage_benefit_monthly') %}
{% set pv_to_grid = states('sensor.pv_to_grid_benefit_monthly') %}
{% set pv_own_value = 0 if pv_own_usage == "unknown" else pv_own_usage | float %}
{% set pv_to_grid_value = 0 if pv_to_grid == "unknown" else pv_to_grid | float %}
{{ (pv_own_value + pv_to_grid_value) | round(2) }}
- platform: template
sensors:
total_pv_yearly_benefit:
friendly_name: "Total PV Yearly Benefit"
unit_of_measurement: '€'
value_template: >
{% set pv_own_usage = states('sensor.pv_own_usage_benefit_yearly') %}
{% set pv_to_grid = states('sensor.pv_to_grid_benefit_yearly') %}
{% set pv_own_value = 0 if pv_own_usage == "unknown" else pv_own_usage | float %}
{% set pv_to_grid_value = 0 if pv_to_grid == "unknown" else pv_to_grid | float %}
{{ (pv_own_value + pv_to_grid_value) | round(2) }}
- Apex chart code:
type: custom:apexcharts-card
graph_span: 31d
span:
start: month
stacked: true
header:
show: true
title: PV Savings Current Month
show_states: true
colorize_states: true
series:
- entity: sensor.pv_own_usage_benefit_daily
name: Own usage
yaxis_id: first
type: column
group_by:
func: max
duration: 1d
show:
in_header: false
legend_value: false
- entity: sensor.pv_to_grid_benefit_daily
name: To Grid
yaxis_id: first
type: column
group_by:
func: max
duration: 1d
show:
in_header: false
legend_value: false
- entity: sensor.total_pv_daily_benefit
name: Total
yaxis_id: first
type: line
stroke_width: 0
unit: €
show:
extremas: true
in_header: false
legend_value: false
group_by:
func: max
duration: 1d
- entity: sensor.total_pv_monthly_benefit
unit: €
yaxis_id: second
name: Total
show:
legend_value: false
in_chart: false
- entity: sensor.pv_own_usage_benefit_monthly
unit: €
yaxis_id: second
name: Own Usage
show:
legend_value: false
in_chart: false
- entity: sensor.pv_to_grid_benefit_monthly
unit: €
yaxis_id: second
name: PV to Grid
show:
legend_value: false
in_chart: false
yaxis:
- id: first
decimals: 2
apex_config:
tickAmount: 2
logarithmic: false
- id: second
show: false
And the result should be like this (Its’ winter in Estonia, so no sun):
And to have investment VS benefit you should to utility meter that will not reset and then compare this number to your investment. Make some template sensor that will just subtract from the investment or does a presentage calculation or if you have bought the PV system with financing compare monthly and yearly cost vs benefit or whatever you can think of.
