diALiNG FOR dOLLARs Controlling thermostats and
temperatures produces low-cost energy savings
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JUsT A siNGLE dEGREE ChANGE CAN
shARPLY AFFECT ThE AMOUNT OF
ENERGY YOU UsE and the dollars you
spend. Your buildings can experience energy
savings between 2 to 4 percent, per degree by
which set temperature points are raised or lowered during the cooling and heating seasons,
respectively, (depending on location, equipment
efficiencies and other factors).
Throughout the real estate industry, a very
narrow range around 72 degrees Fahrenheit is
typically the standard set point in both summer
and winter. In practice, optimal temperatures
vary, based on geographic locations, personal
preferences, and even clothing styles. During
the summer in Miami, for example, you may be
able to raise your set point temperature as high
as 76 degrees because tenants will be dressed for
the hot weather outside. In colder climates—
Chicago in the winter—you may be able to set
the temperature at 68 degrees since tenants will
bundle up against the snow and wind.
Experiment with adjusting set points one
degree at a time, but remember, you won’t
please everyone. Aim for the set point that
makes the majority of tenants comfortable and
achieves energy management goals.
Be sure to lock or remove thermostats in
publicly accessible spaces to prevent unauthorized adjustments. Evidence shows if the
chief engineer controls the temperature, overall
energy performance and tenant satisfaction will
be greater than if tenants make frequent adjustments. Energy costs can be all over the map in
the latter case and systems will work harder—
increasing wear and tear. If you do allow tenants
to control thermostats, reset them to the optimal set point each night so tenants’ overrides
are only temporary.
Another good practice is to calibrate thermostats periodically, ensuring that they are
measuring the true temperature. The U.S.
Environmental Protection Agency (EPA) estimates calibrating thermostats can produce
whole-building energy savings of up to 3 percent. You can purchase an inexpensive temperature gauge, measure the temperature at
each thermostat, compare the two readings,
and if necessary, adjust the thermostat reading.
Further, encourage building engineers to verify
that actual temperature readings in the building match the temperatures represented in the
energy management system (EMS) or building
automation system (BAS).
Make sure thermostats are properly placed
in areas you want to condition. Thermostats
located near doorways, for example, can give a
misleading picture of the temperature in tenant
spaces and cause HVAC systems to work harder
for no reason. Additionally, thermostat locations
sometimes change as a result of space recon-figurations that happen during tenant improvements.
If you can control temperature set-backs with
an EMS, optimize your HVAC schedule according to tenants’ hours of occupancy. In general,
during unoccupied hours, set temperatures back
a minimum of 10 degrees (without going below
55 degrees during the heating season and above
88 degrees during the cooling season).
You’ll find you can squeeze out energy savings just by managing temperatures. Keeping
a sharp eye on energy efficiency, along with
educating tenants, will reward you with more
than an improved bottom line—tenant retention, a higher environmental consciousness and
a reputation for progressive property management. n