how to read your energy for heating?

Usually, the energy to keep your house and your family warm and convenient makes the biggest part of your daily CO2 footprint. So, time to monitor it daily – to save energy, cost, and CO2

The tricky thing is to obtain the raw data = pulses, numbers, times into your mini computer, such as an 8266 device, like as a Wemos. Calculating the Kilowatt-hours (kWh), tons of CO2, and forwarding it to your Home automation system via MQTT is an easy step 2.

if you have your own heating source – single family house

my house heats with a pellets oven (little wooden sticks, almost CO2 neutral). So, the tricky thing was to count the kilograms of wood shuffled into the oven.

here is a scheme of the pellet oven. A spindle shuffles the pellets into the oven. All I needed to do was to detect if the spindle motor on the lower left was switched on.

as this motor runs on 230V – play safe: use a professional device to read and forward the pulses. My recommendation is a Shelly i3 for ~10€

Now, let us calculate the number of spindle starts into Kg Pellets into CO2:

  • one spindle start shuffes 10 gramm of pellets (empirically detected)
  • one Kg of Pellets generates 5KWh of energy
  • CO2 generated: 23g / kWh  
  • or  115g CO2 per Kg or 0.041Tons per year
  • Divide by the number of residents
  • CO2 emmissions by type of energy: see here or here

other sources of heat in your house

natural gas

Most likely, you will find a meter for your gas in your basement. Although i don’t have personal experience with it, i like the solutions in Pinterest. Please try yourself and let me know which worked for you

If you are lucky, your gas counter sends out magnetic pulses. You can test it easily with the compass of your smartphone. Found the solution via Pinterest here

The high end solution for each counter displaying some digits (regardles if this is water, oil, gas or whatever), is OCR = optical character recognition
found here

One heating for multiple appartments

now it gets a bit more tricky to count your portion of the CO2 emmisions.

Let’s evaluate the cases

if you are lucky, there is one counter for all your radiators – or underfloor heating covering the entire appartment.

Check if it has a pulse or LED output that you can pick with a simple 8266

Worst case, you have nothing else than radiators, and those mechanical or radio energy counter
I don’t have a ready-to-use solution for you in this case. However, here is an idea.

Found this tricky solution how to automate your heating:

a smart guy added a 8266 wifi module to a simple 10 Eur stand alone thermostat – and is so able to remote-control all his radiators. If this adds 2 temperature sensors for ingoing and outgoing water temperature: heat counter is ready, including setpoint automation! read here

Community: how can you help?

Please tell me on your solutions: how to measure energy for heating

means: From kg Pellets / liters of oil / cubic meters of gas into a wifi module, and in best case forwarded via MQTT

means: did you manage to count your energy consumption in a building.

Dear heat meter companies: Please consider to push your appartment readings to the residents! Whatever protocol works for you – preferring MQTT of course