I am very disappointed about the level of detail in the Nest history and the monthly Nest Home Report from my new Nest V3 Learning Thermostat that I have since a month. I was expecting more intelligence from a Google product.
What I want in the history display is more information about the inner temperature. I would like to see a graph on how the house warms up after the lower temperature in the night. Also I want in the same display a graph of the hourly outside temperature. The Nest Home Report is useless, since the number of hours is very dependent on the outside temperature and therefore it makes no sense to compare that with previous months.
What is needed is something called 'degree-days'. That is the number of degrees in difference between average inside temperature (settable, e.g. 18 degrees, or calculated by the scheme of inside temperatures by the Nest thermostate) and the hourly or average outside temperature per day. In the history display and monthly report should be detailed how many hours of heating are needed per 'degree-day'. In case of modulating heaters controlled by the OpenTherm protocol, the hours of heating should be adjusted by the level of modulation. If the maximum power of the heater is known, the hours of heating can be calculated into the number of kWh's of energy. This is only what can be used to judge energy savings over time, independent of the outside temperature. See the website www.mindergas.nl, on how this is reported by readings from the gas meter.
Is this something that can be added in future updates of Nest firmware?
Regards,
Frits.
