A Power Consumption and Cost Plugin for Pimatic Devices

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I would like to know the realtime power consumption and cost of the activated (switched on) devices.

For example a spotlight device using 20W has been activated for 6 hours until now.

Calculate Consumption: A spotlight using 20W * 6 activated hours = 120Wh or 0,120kWh until now

Calculate Cost: 0,120kWh * €0,23 energy price per kWh = €0,0276 until now (* 365 days = €10,074 cost per year)

ConsumptionCost Plugin

• Should have a attribute for energy price per kWh
• Should have a attribute for currency

ConsumptionCost Device

• Device usage in kWh (activated until now)
• Device usage in cost (activated until now)

ConsumptionCostMonitor Device

• Should have (a) reference(s) to (a) switch device(s)
• Should have an optional reference to an attribute representing the current power consumption of the switch. (if not present device wattage will be used)
• Should have a attribute for hours of operation
• Should have a attribute for device wattage

Wow, this is a nice idea! Not very accurate but it gives you an indication I don’t know if its possible to get the time that a switch is activated?

@Pimagical Nice idea. However, rather than adding Wattage to the HomeduinoRFSwitch I would create a new plugin with a device type which has a variable reference to the switch state and a property to set the wattage of the consumer attached to the switch. This way, you can cost monitor all kind of switches. Even better, if a switch is capable of measuring consumption the device can also take this into account.

Have a look at pimatic-dewpoint, for example, which takes a variable reference to a humidity and a temperature sensor value and calculates the dewpoint temperature. The consumption & cost plugin could be implemented in a similar way. I am happy to collaborate on this if it gets enough upvotes.

@sweebee I think it is probably good enough to monitor the switch state events and to take a timestamp, e.g. Date.now() when the switch has been turned on. Then the monitoring device can calculate cost at fixed time intervals (e.g. using setInterval()) until the switch is turned off.

@sweebee and @mwittig Very nice to hear! I will take a look at pimatic-dewpoint.

@Pimagical I think it would also be nice to an attribute like “hours of operation”. For fixed wattage this can be easily from the kWh, however, assuming the plugin will also support measurement of current usage it would be better to count time in operation, e.g. using the time intervals for updating kWh und cost values.

Hi

does someone do it ?

@kreg Nothing, I am aware of. Started a new project. Give me four weeks to complete it. You can track the project at https://github.com/mwittig/pimatic-energy-monitor

Nice! For interoperabity, maybe it is an idea to make it possible to set the price for 1 kWh both static in the config or by referencing to a variable. This way, the price could (hypothetically speaking) be fetched directly from the energy supplier.

Also, at my place there is a distinction in price between power used during daytime and power used during night-time. It would be nice if this could also be included.

Keep up the good work

@denniss17 Thanks for the input! This is a good idea. I’ll take it into account.

@mwittig that’s really nice! I will track your progress on this

Could be nice also to have daily/weekly/monthly/yearly values.
Also m3 in addition to kWh

@mwittig For developing a consumption plugin @xCite86’s rules can help: https://forum.pimatic.org/topic/1681/monthly-logging