By Marty Watts,
President and CEO, V-Kool
Consider the following reality:
- Almost one kilowatt hour of electricity out of every five
consumed in the US
is used to cool buildings.
- 18% of US
electricity consumption is used for air conditioning a great deal of that in
large commercial buildings.
- Air conditioning contributes to global warming not only
by increasing the use of electricity generated by coal and natural gas but
exacerbates the problem by releasing refrigerants into the atmosphere. North America, with only 6% of the worlds population,
accounts for nearly 40% of the worlds refrigerant market.
- Obviously, air conditioning is not limited to this
hemisphere. According to Hong Kong Polytechnic
University, Hong Kong is one of the most overly air conditioned cities in the
world. A temperature rise of just 1 degree C in a 40-story building in that
city would save almost $26,000 annually in energy cost.
- Worse yet, much of the worlds conditioned air is going
literally out the window. In the US, despite heavily insulated walls
and ceilings and the popularity of low-e glass, 25%-35% of the energy used in
buildings is wasted due to inefficient glass. So, it should come as no surprise
that poorly performing glass is responsible for >10% of the total carbon
emissions in the US
annually and is a major contributor to global warming.
Despite the undeniable causal relationship between air
conditioning, staggering energy cost and potentially catastrophic climate
change, apparently corporate America
is willing to pay the price. Is this because air conditioning is so well
respected if not beloved by the US
workforce and public at large? Though thats what HVAC proponents would like
you to believe, consider the following:
- According to the International Facility Management
Association, office temperature ranked at the top of office complaints.
Anecdotal evidence strongly suggests most office workers complain that the
temperature is too cold and that air conditioning is the cause.
- Cornell
University reported that
75% of workers polled voice dissatisfaction with the temperature or air quality
of their workplace.
- Retail venues do not escape criticism. On the web
numerous complaints accuse Starbucks stores of being too cold for comfort.
Though office workers as well as coffee servers and their
patrons may complain about frosty indoor temperatures, for years, if not
decades, HVAC enthusiasts have repeatedly asserted that productivity improves
as temperatures decrease. In fact, that was the hypothesis assumed in a recent
study by Cornell University of the impact of temperature
on office workers productivity.
Instead, the studys authors found when temperatures were
at 68 degrees or below, typists were keying 54% of the time with a 25% error
rate. When temperatures were at 77 degrees, the same typists were keying 100
percent of the time with a 10% error rate. Typing errors fell by 44% and typing
output increased 150% when office temperatures were increased from 68 to 77
degrees.
Workers in a cold office not only make errors but cooler
temperatures can increase a workers hourly labor cost by 10% estimates Alan
Hedge, professor of design and environmental analysis and director of Cornells
Human Factors and Ergonomics Laboratory. Employers would save about $2 per hour
per worker with warmer office temperatures.
In addition to chilly, less productive employees, air
conditioning can lead to real medical problems. Despite claims that air
conditioning improves indoor air quality consider the following:
- The French Institute of Health and Medical Research
asserts that HVAC systems in office buildings have been shown to be associated
with several adverse health effects in terms of morbidity and mortality. The
assumption is this may be the result of HVAC systems operating not
abnormally, but as designed.
- According to the Common Colds Centre, Cardiff School of
Biosciences at Cardiff University in the UK, air conditioning itself may
contribute to infection with common cold viruses. The Centres web site
contends that The lining of the nose is covered with a thin layer of mucus
which protects against infection. Since air conditioners extract moisture from
the air they may cause some drying of the protective mucous blanket in the nose
and predispose to infection. The cold air may also help viruses to establish a
hold in the nose as they reproduce better in a cold nose.
- Additional studies have shown that people exposed to air
conditioning are more susceptible to colds, flue and other minor ailments than
those who are not. This comes as no surprise when in some cities summer
temperature differences between indoors and out span a range of 30 degrees or
more.
- According to an internal study conducted by the ECOS
Corporation, Sydney, Australia, Intensive air
conditioning all year long was identified as having a strong negative impact on
the quality of the office environment.
Air conditioning burdens employers with increased costs,
decreased worker productivity, unhappy office occupants and a workforce whose
health may be in jeopardy as a result of exposure to conditioned air. The cost
in terms of electricity use and climate change has been noted. Why then is the
temperature of so many American offices and retail environments more like meat
lockers than places of human habitation?
Though we can only speculate, no doubt, fear of Sick
Building Syndrome (SBS) and possible employee and tenant generated lawsuits
motivates building owners and facility managers to lower temperatures no matter
what the cost. More HVAC, more often is the knee-jerk response of building
management as the one-size-fits all solution to indoor air quality problems.
This, despite indications that excessive HVAC operation may in itself be a
cause of the very SBS so used as an excuse to lower the temperature.
It is important to note that according to the US
Environmental Protection Agency (EPA), the term "sick building
syndrome" is used to describe situations in which building occupants
experience acute health and comfort effects that appear to be linked to time
spent in a building. SBS is not to be confused with "building related
illness" (BRI) which the EPA explains applies when symptoms of diagnosable
illness are identified and can be attributed directly to airborne building
contaminants. Given these definitions and the facts noted, it is clear, that
SBS may be caused directly by air conditioning systems alone.
As we have demonstrated, persuasive evidence suggests that
air conditioning in American offices and retail establishments is an
out-of-control technology whose costs far outweigh its benefits. Permit us to
offer some alternative approaches to more effectively mitigate or entirely
prevent building overheating.
- HVAC deals with heat after it has been generated in the
building or transmitted through window glass. For those buildings with
significant amounts of glass through which solar energy causes overheating,
heat-blocking window film can stop heat before it enters the building and
reduce the need to aggressively operate air conditioning systems.
- While dramatically lowering indoor temperatures in
buildings with air quality problems may improve conditions, temperature reduction
is not as effective as removing and replacing furnishings and building
components that are off-gassing nor is it as effective as eliminating sources
of water and condensation that create mildew and mold.
- Maintaining adequate ventilation in a building to
mitigate stuffy air does not require lowering temperature.
- For HVAC vendors to contend that reaction to temperature
is subjective or that building occupant complaints are essentially irrational
is to ignore well-documented evidence that the vast majority of people will be
comfortable in offices in which the temperature is kept at 68 degrees in winter
and 78 degrees in summer. Humidity levels should be between 30 and 60%.