I presume all makes and models of ASHP come as standard with the makers own controller/thermostat.
It also appears that the situation is very similar to what exists with traditional gas boilers in that ASHP generally are not open to smart home platforms and integrating with other systems. A slight possible exception would be Samsung and the fact their products can integrate with their own Smartthings platform. However they still do not integrate with other platforms directly such as Matter.
One topic would be to discuss whether there are genuine beneficial cases for such support.
However another slightly different topic is to discuss whether there is any merit to using an alternative controller/thermostat to the manufacturers own solution.
I have so far identified the following potential alternatives and of course they all claim to be better than the manufacturers standard solution.
It seems the main promoted features are -
Support for agile energy tariffs
Support for Greener Grid Payments aka Demand Flexibility Service
Support for a mobile app (although manufacturers propriety solutions usually include this)
Support for geo-location tracking to automatically reduce heating when no-one is at home
Support for Internet weather data and in some cases your own smart weather station for better weather compensation adjustments
At least one claiming to use AI to optimise settings
Remote monitoring of the hardware health of your ASHP system
Tado at least does support Matter and hence can integrate with smart assistants and other systems, they also seem the only solution so far which links an ASHP to smart TRV valves although I am not sure of the benefit of this
I am interested to hear other people views on whether it is worth considering such alternatives. The Homely whilst not necessarily the most attractive or powerful seems to deliver the most benefits.
It should be noted that if you have something like a Tesla Powerwall and an agile energy tariff you can do time shifting of demand even without any of these other controllers as you would draw from the battery at these times and still get savings or even the DFS payments.
Note: not all of the above are as yet available in the UK or in other countries, Homely is available in the UK, Tado is not available in the UK yet but is in some other EU countries.
It depends on the capabilities offered by the heat pump manufacturerās built-in controller/thermostat
Note that in some case these can vary by location - especially with features like adapting to time-of-use electricity tariffs, which are country-specific (or electricity-supplier-specific)
It also depends on the provision made for the user to configure these capabilities - e.g. to influence the trade-off between Comfort and Cost when adapting to cheap-rate electricity tariffs
It depends on the occupancy profile for the property
Is everyone out of the house during week-days?
It depends on the thermal characteristics of the property
Especially the āthermal massā - i.e. the extent to which the house tends to act as a āheat batteryā
Also the magnitude of passive solar gain, which can be very helpful on cold-but-sunny days
Probably also the sizing of the heat emitters (e.g. radiators) and whether these are able to re-heat the property quickly or barely maintain temperature when running 24x7
It depends on what other Home Automation and Energy Management systems are installed
Youāve already flagged the potential implications of a home battery storage system
I use the fact the intruder alarm is set as a simple indication of non-occupancy, which is a lot less complicated than GPS-tracking multiple occupantsā phones
My own experience is with a NIBE GSHP in a house with very high levels of insulation and significant thermal mass which is occupied almost all the time:
The NIBE weather compensation algorithm is excellent and appears to control the temperature to within 0.1 degrees, so no issues there
The house takes many hours to cool down so thereās no point trying to āprofileā the temperature at different times of day - I run it at the same set-point 24x7
On sunny days in Winter there can be appreciable passive solar gain, which is A Good Thing
This makes the house slightly over-heat which the heat pump senses via the indoor temperature sensor, so it backs off the heat delivery until the house cools nearer to the set-point
I sometimes wonder if I could improve matters by predicting an upcoming sunny day and reducing the set-point in the early hours of the morning with the expectation of solar gain later - but Iām currently on Intelligent Octopus Go, so cheap electricity until 05:30 which itās a shame to miss out on
Because I have a Ground-Source system, thereās no efficiency penalty from running the heating overnight - even if the air is freezing the ābrineā coming in from the ground loop is typically around 8 degrees, all the time
NIBE have a very capable API (as used by their smartphone App) which I use to download operational parameter data and could (but donāt currently) use to make adjustments to settings
This also covers the āremote monitoringā aspect and will send notifications for any issues to both me and my installer
NIBE offer a āSmart Price Adaptionā facility to make the unit work harder when electricity is cheaper and back off when it is expensive - but this does not currently support the UK market
So for my scenario I personally could not justify the addition of a third-party controller. Iād also be concerned about the complexity of having multiple controllers each thinking they were āin chargeā - but I have a relatively capable system doing a fairly simple job, in a house that needs relatively little heating.
My advice would be to clearly understand the mechanism by which one of these third-party controllers aims to either save money or improve heating control and consider other ways of achieving (most of) the same effect using the built-in controller. For example, when I was previously on the Octopus Agile tariff I used the NIBE controllerās scheduler to āblock outā 16:30 - 17:00 every day, which was a crude way of avoiding the highest electricity prices.