The Energy Stats page on this website provides a live view of how electricity is being generated, stored and used around my home.
What began as a relatively conventional solar and battery installation has gradually developed into a much broader home energy project involving solar panels, a GivEnergy system, BLUETTI power stations, EcoFlow batteries and Octopus Agile electricity prices.
Home Assistant brings these different systems together, while the website turns the most useful information into a simple public dashboard.
How live is the data?
The dashboard receives updated information from Home Assistant approximately every 30 seconds.
This is frequent enough to show changes such as an appliance being switched on, the solar output increasing or a battery beginning to charge. There may occasionally be a short delay between something happening in the house and appearing on the website.
The figures will naturally move throughout the day as household demand, solar generation and battery activity change.
Grid
The Grid figure shows the electricity currently passing between the house and the national grid.
When the house needs more power than the solar panels and batteries are supplying, electricity is imported from the grid.
When solar generation or deliberate battery export exceeds the demand from the house, the surplus is exported instead.
This figure can change very quickly when large appliances, battery chargers or the electric vehicle are switched on.
Solar
The Solar figure shows the current output from my 6.5kW solar array.
Solar production depends on the time of day, season and weather conditions. Passing cloud can cause the output to rise and fall considerably within a few minutes.
Home usage
Home shows the total amount of electricity the house is consuming at that moment.
This includes normal household appliances as well as the equipment supported by the main electrical system. Larger loads such as cooking appliances, washing machines and vehicle charging can cause a noticeable increase.
The important distinction is that home usage does not necessarily mean grid usage. The power may be coming from solar generation, stored energy or a combination of several sources.
GivEnergy battery
The GivEnergy system is the main battery installation for the house, with approximately 19kWh of storage.
Its state of charge is shown as a percentage, while the live power figure indicates whether the battery is currently charging or supplying energy.
Home Assistant and Predbat use solar forecasts, expected household consumption and electricity prices to help determine when this battery should charge, discharge or preserve its stored energy.
BLUETTI AC300
My BLUETTI AC300 is connected to four B300K expansion batteries and provides approximately 11kWh of additional storage in the garage.
Among other loads, it supports three fridges. Its live figures show the current state of charge, power usage and whether the system is charging.
Every afternoon, Home Assistant examines the following 24 hours of Octopus Agile prices and calculates how many half-hour charging periods the AC300 is likely to need. It can then select the cheapest suitable periods instead of using the same fixed charging time every night.
BLUETTI AC200L
The BLUETTI AC200L provides separate power support in the lounge.
It runs equipment including the fibre broadband modem, television, Sky box and Sonos system. Keeping these devices on their own battery system provides useful resilience during a power interruption and reduces the continuous demand placed on the main house battery.
Its state of charge and current power level are also displayed on the dashboard.
EcoFlow battery group
The EcoFlow section represents a group of EcoFlow STREAM AC Pro units operating as a combined system.
These units provide distributed storage around the house and can respond dynamically when demand becomes high.
During the evening, an automation monitors the output from the main GivEnergy battery. If the GivEnergy system approaches its preferred discharge limit, Home Assistant can increase the EcoFlow contribution. When demand falls again, the EcoFlow output is reduced.
This allows the stored EcoFlow energy to be preserved when it is not required while remaining available to support heavier household loads.
Octopus Agile prices
Octopus Agile electricity prices change every 30 minutes and are published in advance.
The dashboard shows the current import price, helping explain why the battery systems may be charging, holding their energy or supplying the house at a particular time.
A low or negative price can make grid charging attractive. During an expensive period, the house can instead make greater use of stored energy.
The price graph shows how the cost changes across the day and makes the selected charging periods easier to understand.
Watts and kilowatt-hours
The dashboard uses two closely related measurements:
- Watts (W) and kilowatts (kW) show the rate at which electricity is being used or produced right now.
- Kilowatt-hours (kWh) show the total quantity of energy used, generated or transferred over a period of time.
A 2kW appliance running for 30 minutes would consume approximately 1kWh of energy.
Why display all this publicly?
I created the Energy Stats page to make the behaviour of the system easier to see and understand.
It demonstrates how products from several manufacturers can work together when their data is brought into Home Assistant. It also shows why intelligent control is about more than simply adding batteries: the real benefit comes from deciding when to charge them, when to use them and when to preserve their energy.
The dashboard will continue to evolve as I improve the automations, add clearer graphs and learn more from the data.
You can view the live figures on the Live Energy Stats page and see what the house is doing right now.
This is an independent home automation project. I’m not currently sponsored by any of the companies mentioned.
