February ’23 Energy Use Numbers

POSTED ON March 8, 2023

Seeing is supposed to be believing. 

“Complicated computer models are less accurate than simple ones. A study sponsored by the Energy Trust of Oregon compared the accuracy of four energy software programs. Surprisingly, Michael Blasnik’s Simple spreadsheet proved to be more accurate than models that required far more inputs.”


February has been a cold month, we have good third party documented statistics for the month that give us insight into how well we are doing. This is for the entire Burnside Boardwalk building, all 31 units, all 17500 sq.ft.  We have put temperature and humidity sensors in all the rooms and CTs on all of the circuits. 

Energy Used – to heat Burnside Boardwalk in the month of February

AVERAGE Room Temperature73.25 F
AVERAGE Humidity42.50
TOTAL energy used in the MONTH of Feb1,493 KWH /Mo
AVERAGE energy used per DAY53.3 KWH /Dy
AVERAGE energy used per HOUR2.21 KWH /Hr
AVERAGE energy AS HEAT used per HOUR7,580 BTUs /Hr
The energy used includes the heat pump and 2-1.6 hp circulating pumps. 

Heat Pump Cycles – with average unit temperature of 72-73 degrees.

Outside Temperature
Range in Farenheit
Heat Pump Cycle
Hours On / Hours Off
Very cold18 – 301 hr / 1 hr
Cold30 – 401 hr / 2 hrs
Chilly40 – 501 hr / 6 Hrs
Mild50 <off

When the heat pump is operating

Circulating Pump Volume15 GPM
Temperature Raise5 F
Heat Pump Output (15 x 5 x 8.4 x 60)37,800 BTUs
@18000 btus per KWH
Circulating Pump Energy Used2.11 KWH
Heat Pump Energy Used2.09 KWH
TOTAL Energy Used4.2 KWH

Models are rife with errors and the more inputs the more likely that the model is wrong.  Energy Trust of Oregon has a paper out that a spread sheet is as accurate or more accurate than a complicated model.  In this case the actual numbers should be the overriding data set. The quest for net zero has been diluted by solar arrays and outside purchases that make the best superfluous. 

Our quest is to have the lowest EUI of any residential building, below 6 with most of that usage from uncontrollable “miscellaneous” equipment. When put onto the array, Burnside Boardwalk will produce 3 times more energy than it uses

Here is the average temp in the different rooms. Our tenants control their room temp by cracking a window when it is too hot. What social equity for my impacted tenants to be warm. Please note that the average temperature is 73.25 degrees with 42 % humidity. Almost perfect for a mean radiant temperature it meets the dry bulb requirements of 68 but far exceeds the MRT needs.
Here is the energy used by the heat pump and the 2 circulating pumps. As the month went on we were able to tune the system better. We may be able to squeeze even more out of the heat pump by changing the frequency of the pumps on and off plus getting more efficient pumps and the PLC can adjust to weather.
Here is a picture of the c-more screen that controls the heat pump and circulating pumps through a PLC, it would be nice to talk to some one about how cycling the pumps so that the ground loops can regenerate and how the radiant circulating heat allows the entire mass of the building to act in unison to smooth out the heat.