ENERGY STAT: ELECTRICITY TRANSMISSION AND DISTRIBUTION LOSSES AVERAGE
ABOUT 6% OF THE TOTAL ELECTRICITY TRANSMITTED ANNUALLY, ACCORDING TO
THE ENERGY INFORMATION ADMINISTRATION.
The New Frontier in the Temperature Wars
Fed up with recurring temperature complaints? The cause may
be due (at least partially) to the
biological differences between occupants
in the same space.
A new study in the journal Nature
Climate Change blames the differences in
metabolic rates between men and women
for much of the temperature preference
disparity. Its authors claim that the thermal comfort model upon which indoor
climate regulations are based overestimates the female biological rate by up
to 35%, resulting in buildings that are
uncomfortable year-round for women.
➙However, ASHRAE disputes the re- searchers’ findings, saying that Standard
55 (which specifies how to produce
indoor thermal conditions that are acceptable to the majority of occupants) is
based on a comfort index developed on a
1,000-subject study that included equal
numbers of women and men.
“In the main studies where both
groups did the same sedentary work and
wore the same type of clothing, there
were no differences in preferred temper-
ature,” says Bjarne Olesen, a member of
the ASHRAE Board of Directors, thermal
comfort researcher, and former chair of
the Standard 55 committee. “The reason
why some field studies find that women
prefer a higher room temperature than
men is attributed to the level of clothing.
Women adapt their clothing to summer,
while men are still wearing suits and ties.
If the thermostat is set to satisfy the men,
then women will complain about being
Whatever the source of the disagree-
ment, the consequences are clear: wasted
cooling energy, uncomfortable workers,
and even impacts on health and produc-
8 Considerations for Advanced Lighting Controls continued from page 13
space or adjust how fixtures are zoned,
Gentry recommends. Do you need to call
the vendor and request a service technician, or is it easy enough to make the
needed changes in-house?
You should be able to adjust the level
of control you have, Piccirillo recommends, especially if this is your first
foray into lighting controls.
“I’d start with an open office or
conference room and start with the
basics. Look at doing a relay panel and
just go to a relay-based level of control
where you can dim all of the lights in the
space at the same time,” Piccirillo says.
“I would recommend as a best practice
that you eventually go all the way to a
granular level of control where you have
an interface that lets you control each
fixture in the area. This way it’s almost
As the space changes, your objectives
as an FM may change with it, Piccirillo
“You might start by setting the expectation that your team will set up the
relay and enable group control of the
luminaires,” says Piccirillo. “Next year,
you might get a new target of shaving
20% off of your energy consumption.
You can go back to your boss and say ‘No
problem – we’ll institute individual fix-
ture control and I’ll dim the light levels
over this row of cubicles during certain
hours because no one is occupying
them.’ That way you now have individual
fixture savings and it didn’t require any
new capital to make it happen. All you’d
have to do is go into the remote software
managing this network and modify your
As you peruse your options, ask vendors how scalable each system is. Can
you expand its reach one department,
floor or structure at a time? If so, you can
start by perfecting your strategy in one
area, then moving on when you’ve confirmed your new system is saving energy.
“Open office areas and parking garages
are good places to start,” Piccirillo notes.
“In warehouses, lighting controls are
almost a no-brainer when it comes to
energy savings, partly because they operate 24/7 so there are more opportunities
to reduce consumption. Office areas may
not be entirely occupied every shift and
just have certain rows or cubicle that are
occupied. Those areas are great candidates for savings.”
Does the system you’re looking at
allow you to modify light levels to the
needs of each occupant? It’s worth ask-
ing, as most offices are overlit to compen-
sate for how lights dim over time.
“Architects overlight buildings in
expectation of it degrading to a level
that’s acceptable, but in the meantime
there’s too much extra light provided to
the facility and that’s a huge energy loss,”
explains Gentry. “It also causes significant occupant discomfort. If you work at
a computer, that alone probably provides
you with enough light to work – the
overhead light is doing nothing for you
other than acting as a source of glare. In
most cases, we can reduce office lighting by 40 to 50% and still have satisfied
8) Daylight Harvesting
The trend toward glass curtainwalls
and large banks of windows makes
daylight harvesting a handy feature for
lighting control systems, Gentry says.
“When you have floor-to-ceiling windows, the amount of daylight harvesting
you can get increases tremendously from
light filtering into the building,” adds
Gentry. “You can get the biggest impact
from daylight harvesting if you have a
system that not only controls fixtures
near the windows, but also compensates
for daylight further into the building.”
Janelle Penny janelle.penny@buildings.
com is Senior Editor of BUILDINGS.