Utility Grade

Wow, I can’t believe it’s already been eighteen months since my last two posts describing electricity and water usage at the Byrne residence!

In preparation for this particular post, I did go back to Observations about electricity usage… and updated the two charts reflecting July 2012 to June 2013 and July 2013 to June 2014 electricity usage. I did not, however, update the chart embedded in A year [and counting] with a smart meter…, opting to preserve it since it’s the only post reflecting usage between January and May of 2012.

First, a couple of notes on the conventions you’ll see used in the three (3) graphs below:

  1. Dates without any data are reflected with ∅, (apparently there haven’t been any since late 2012/early 2013).
  2. The temperatures shown are average daily temperatures in Fahrenheit.
  3. If I had to average temperatures to fill a gap, they are shown in both bold and italics, (there were no occurrences since October 2012).
  4. The color key for temperatures is blue for cooler temperatures, (with the darkest blue being at, or below, 32 degrees Fahrenheit), 72 degrees Fahrenheit is represented by white, and temperatures at, or above, 90 degrees Fahrenheit are deep red.
  5. The color key for kWh per day is green for the lowest values, (meaning values below 10 kWh for the entire 24 hour period), yellow for values hovering around 50 kWh for the entire 24 hour period and red for values at, or above, 100 kWh for the entire 24 hour period.

Next, a few observations about the 12 months of data in aggregate:

  1. Total usage from July 1st 2012 to June 30th of 2013 was 20,200 kWh. Total usage from July 1st of 2013 to June 30th of 2014 was 19,600 kWh. Total usage from July 1st of 2014 to June 30th of 2015 was 21,800 kWh. Yes, you’ll notice an uptick – we used 9.5% more during the 2014-2015 period than the average of the prior two periods (2012-2013 and 2013-2014). I believe this is reflective of the simple fact we’ve occupied the house full-time vs. occupying it for what amounted to less than three months in prior years.
  2. The average daily usage for the 2014-2015 period was 59.5 kWh vs. an average daily usage of 55 kWh for the 2012-2013 and 2013-2014 periods, (and roughly the same 9.5% increase noted above).
  3. I did a little research into temperature and precipitation levels captured at a nearby weather reporting station located less than a mile from the Byrne residence. Between July 1st of 2012 and June 30th of 2013, the highest recorded temperature was 112 degrees Fahrenheit, lowest recorded temperature was 23 degrees Fahrenheit, the average temperature was 70 degrees Fahrenheit and annual precipitation measured 15.9 inches. Between July 1st of 2013 and June 30th of 2014, the highest recorded temperature was 106.8 degrees Fahrenheit, lowest recorded temperature was 30.2 degrees Fahrenheit, the average temperature was 71 degrees Fahrenheit and annual precipitation measured 9.78 inches. Between July 1st of 2014 and June 30th of 2015, the highest recorded temperature was 107.0 degrees Fahrenheit, lowest recorded temperature was 28.0 degrees Fahrenheit, the average temperature was 71.3 degrees Fahrenheit and annual precipitation measured 21.65 inches.
  4. While there is variability in terms of temperature and precipitation, the variability doesn’t appear to correlate with electricity usage. The stronger correlation seems to be based on occupancy. In essence, occupying the Byrne residence 365 days a year uses [slightly] more energy than if you occupy it only a quarter of the time!

This graph depicts July 1st, 2012 – June 30th, 2013:

This graph depicts July 1st, 2013 – June 30th, 2014:

This graph depicts July 1st, 2014 – June 30th, 2015:

Now, on to my period-specific observations, (starting with July 2014):

  1. In summary, the general trends reflected on these three charts are similar – no profound year-over-year deviations – despite the rather significant change in occupancy trends, (part-time occupancy during fall/winter/spring of 2012, 2013 and most of 2014 vs. full-time occupancy starting in September of 2014 and continuing to the present).
  2. I took a quick look at the last half of 2015 temperature and precipitation data just to see if conditions resembled those from the three 12 month periods noted above, and, in short, they did. Between July 1st of 2015 and December 31st of 2015, the highest recorded temperature was 108.9 degrees Fahrenheit, lowest recorded temperature was 25.9 degrees Fahrenheit, the average temperature was 71.8 degrees Fahrenheit and six months of precipitation measured 4.85 inches.
  3. While temperature-related variation does influence electrical consumption at the Byrne residence, (an estimated 5% fluctuation, based on the 2 1/2 years of data collected while it was being used as a vacation home), it seems that full-time vs. part-time occupancy can have an even greater influence, (an estimated 10% fluctuation, based on 2014/2015 data).

Let’s turn our attention to water consumption at the Byrne residence.

I’ve published some trend data in the past, (see Observations about water usage…), but with almost four years of data captured since the irrigation system was installed, the longer-term trends are starting to become much clearer.

First, a couple of notes on the conventions you’ll see used in the single graph below:

  1. The new irrigation system was activated in May of 2012, (just as we were wrapping up the rather significant landscaping project we undertook earlier that year), thus explaining the lack of data for the months of January through April of 2012.
  2. The data is expressed as gallons consumed per month, as reported by the RainMaster Eagle Plus™ irrigation system controller.
  3. The figures for February 2016 through December 2016 are estimates, (based on 2015 usage), since I’m publishing this post in February.

Next, a few observations about the 48 months of data in aggregate:

  1. Irrigation in the second half of 2012 was significantly higher than in subsequent years, (even the extremely dry spring and summer of 2014), because the focus was getting the new plants firmly established.
  2. The irrigation system was in “rain shutoff mode” for the entire month of February 2013, so there isn’t any recorded usage for that month.
  3. We consulted with Todd Briggs of TRUEFORM Landscape Architecture Studio at the end of 2014 specifically to revisit the irrigation schedule covering September through December, and, as a result, the usage trend in 2015, (as well as the projected trend for 2016), looks much more like the observed 2013 trend, which we regarded as being more in keeping with the actual irrigation requirements for that time of year.
  4. In hindsight, I suspect we over-irrigated in late 2014, particularly in view of the historically high levels of precipitation we received in August, September and November of that year.
  5. Irrigation consumption in 2015 was 51% of the same period in 2012, (i.e. May through December), and this is/was by design. Our goal is – and has been – to carefully manage irrigation, with an eye toward keeping water consumption to an absolute minimum without jeopardizing the landscaping. Notwithstanding the fourth quarter of 2014, I think we’ve done a reasonably good job so far!

H2O usage reported by RainMaster Eagle Plus™ controller:


Oh, right, time to give ourselves a grade. I’m leaning toward a “B-” or “C+” which implies above average, but barely.

Here’s why. While we have implemented quite a bit of technology aimed at improving efficiency and/or carefully regulating consumption, there are fundamental a) design or b) structural elements we must accept – and we do, enthusiastically, I might add – or risk jeopardizing the integrity of either a) the design or b) the structure, neither of which is really an option for us. We made a promise to Bill & Carol and we’re not about to break it. The integrity of the Byrne residence will be preserved on our watch, period.

The trade-off is an easy one for us to make – Martha and I opted to to focus on non-intrusive and/or so-called “reversible” improvements like UV-blocking film on the glass, 90% solar block window coverings, HVAC upgrades, installing Internet-accessible management devices, (e.g. RainMaster Eagle Plus™ irrigation controller, Nest Learning Thermostats, etc.), latest generation Hastings Vola and Toto Aquia plumbing fixtures and even installing Bluetooth-enabled ceiling fans vs. opting for a more radical approach risking compromise of the very thing that makes this house so special – the iconic nature of the design, (thank you Will Bruder), and the superior quality of construction, (thank you Bill & Carol Byrne)!

OK, so maybe I should give us an “A” for effort… 😉

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