Thanks for the reply, @ixu !
LG and others are now making window inverter ACs. I just installed one. Just to make your life difficult.
Some window units have resistive element heating modes.
Industry will no-doubt introduce inverter-based compressor heating modes into window units and they will, hopefully quickly, supersede old-school ACs.
Variable-speed motors are indeed becoming increasingly prevalent! It is exciting that companies are motivated (to whatever extent) to produce more efficient ACs, especially as the world’s cooling needs are monotonically increasing! Even in colder regions, these systems sometimes double as heat-pumps (both inverter-driven and constant speed) and can be efficient alternatives to other heating systems.
This reminds me of another tricky issue in accounting for the seasonality of AC models: lots of people with heat-pumps use the same system in winter (for heating) and summer.
We have done some work in the past modeling inverter-driven fridges. Some of that work might transfer to LG inverter WACs in the future. We haven’t had confirmed examples of users owning this device! Would it be ok if we looked at your data? (tagging @RyanAtSense )
In general, large local variations are more informative to machine learning systems than slow long-term changes.
Side-note: Features defining boundaries of shapes are generally important in image recognition. Thinking in (limited) analogies, constant speed ACs are well defined by the rising and falling edges, while variable speed motors are like a fuzzy blob of unknown extent and fuzziness.
We are continuing to work hard at the problem of recognizing slowly changing shapes! (EVs, inverter-ACs, etc.)
Because weather (temperature & humidity that is) is hyper-local (especially in an urban environment) are you looking in to ways to integrate user-based monitoring?
A great solution here would be for Sense to integrate with Ecobee and Nest. Various external constraints beyond our control (mainly related to access to the smart-thermostat APIs) have stymied our ability to integrate with these devices. Another benefit of thermostat integrations would give us sources of ground-truth for 240 V devices!
We are currently exploring other approaches of getting weather data. (Side note: NOAA’s temperature data is great source for local weather, https://www.ncei.noaa.gov/data/global-hourly/access/ - but as you might imagine, it is not straightforward to get this as a real-time stream)
An additional challenge with directly using temperature for modeling real-time AC behavior (i.e., going beyond average estimates) is that there are a lot of confounders and a long tail of outliers: ACs cycle long, some cycle more often, some houses have poorly specced systems, etc.
Are the cross-overs with Solar output as a weather indicator being considered? Clouds! [The integration here seems key] @kevin1 has done some great exploration on this.
We have done some exploration with temporal and spatial solar output trends. But we haven’t used it for weather modeling. That’s an interesting idea!
BTW: Sump-pump goes on = rain?!
Likely, but not necessarily? I wonder if there are other sources of water? It would be interesting to look at correlations between cloud cover and sump-pump usage.
(I was trying to flesh out the correlation between sump-pumps and rain, and remembered this story, though it doesn’t explicitly mention rain: https://sensesaves.sense.com/dirty-sump-pump/ )