2025 November

November: the sun was out except for a few days, and summer was here albeit will nice cool evenings (median temperature 20 °C). Outside temperatures ranged from 9 to 35 °C, while inside we were a comfortable 18 to 25 °C. The HRV was in the cooling season and the split system was mostly on during the days and off during the evenings when the windows were open. With the sun out the solar production was solid. We had a dozen or so visitors through on International Passivhaus Open Days. Always a fun day to chat with people about our Passivhaus journey.

Temperature from inside and outside the house as the percentage of hours in 0.5 °C bins. I've scaled the temperature in hope that I will be able to use the temperature range for all months. We have made a decision to keep the house above the WHO recommended 18 °C rather than the passive house standard of 20 °C.

Methods: I have taken the 5 minutely data from the wirelessTag sensors and calculated the median temperature for each hour and determined the proportion of hours falling inside of the 20 - 25 °C target temperature (using the R functions 'aggregate' and 'hist'). Inside includes data from the wirelessTag sensors spread across nearly every room of the house. Outside is the data from the wirelessTag sensors outside near the cubby house. The water wall data are not included.

Energy production and consumption: 1. total daily consumption and solar production, 2. daily net energy production (energy produced - consumed), 3. energy independence (1 - (imported / consumed energy)), and 4. solar offset (energy produced / consumed).

Some notes about the energy plots... Currently the batteries are configured to maximise our energy independence, which means we avoid importing electricity. We still import and export electricity to/from the grid as needed. It is also possible to have negative independence when we import more than we consume due to charging batteries and averaging across days. The batteries will also top up from the grid when weather (including fire) warnings are issued to ensure that the batteries are full should the gird power go down. Since we have had the batteries we have experienced about 6 hours without the mains power during which the solar/battery system functioned perfectly and the house never lost power. All of these power outages were during the daylight hours, so our power was mainly supplied by our solar panels with the battery just balancing the supply / demand offsets.

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