2020 May

Another month of house data... The weather is getting quite cool some nights, with enough rain for almost normal moisture back in the system. Of course the big news this month is still COVID-19 (2 adults working from home), but the kids were at school one day per week for a couple weeks before returning to school 5 days a week starting the 25th. The HRV target temperature is set to 23 °C and we even set the heating season to begin when the running mean outdoor temperature drops below 14 °C. We have even run the heater some to bring the house temperature up just a bit. We swapped the HRV core for the ERV core at the end of the month as our part of data collection on the two cores in the Sydney climate.



Percentage of hours in below, within, above the 20 - 25 °C target temperature range for the month.
Inside / Outside% < 20 °C% 20 - 25 °C% > 25 °C
Inside 9% 91% 0%
Outside 95% 5% 0%

Methods: I have taken the 5 minutely data from the wirelessTag sensors and calculated the median temperature of each sensor 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 12 wirelessTag sensors spread across every room of the house. Outside is the data from the wirelessTag sensors outside near the cubby house and HRV intake. The water wall, clerestory and door data are not included.


Quantile temperatures (°C) for the month.
Inside / OutsideMin5%25%Median75%95%Max
Inside 19 20 21 22 23 24 25
Outside 4 7 11 13 15 20 26

Methods: I have taken the 5 minutely data from the wirelessTag sensors and calculated the median temperature of each sensor for each hour and determined the indicated quantiles for each sensor (using the R functions 'aggregate' and 'quantile'). Inside includes data from 12 wirelessTag sensors spread across every room of the house. Outside is the data from the wirelessTag sensors in the cubby house, outside, and HRV intake. The water wall, clerestory and door data are not included.

Monthly electricity data. We were net energy users for the month (1.2kWh/day). Because we don't have batteries, we exported 186.2kWh and imported 223.7kWh.

QuantileEnergy Produced (kWh/day)Energy Net (kWh/day)
Min 2.11 -13.51
Median 14.02 0.18
Max 19.68 8.44

Methods: I have taken the 15 minutely data from the Enphase Enlighten website summed by day and determined the indicated quantiles (using the R functions 'aggregate' and 'quantile'). Energy produced and Energy Produced - Energy Consumed. Note: this only measures indoor electricity usage (doesn't include the rainwater tank pump, the garage door, or the garage lights) because the solar is tied into the inside distribution panel not the meter.

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