The following exchange, concerning the January 2010 article “The Greenhouse-Gas Impact of Various Chiller Technologies” by Gerald J. Williams, PE, LEED AP, took place on HPAC.com via the Disqus comment system. Here, the exchange is edited for length and clarity. To read the full exchange, as well as the article that inspired it, go to http://hpac.com/green/greenhouse-gas-impact-chiller-0110/index.html.

“Mark in St. Louis” wrote:

“With the latest developments in ‘Climategate’ (United Kingdom) and ‘Climategate USA,’ the IPCC (Intergovernmental Panel on Climate Change) pulling its 2035 Himalayan prediction, etc., why is this topic of any relevance?

“CO2 (carbon dioxide) is not a pollutant! If it is, we humans should stop breathing.

“There is no man-made ‘global warming,’ ‘global cooling’ (I remember this scare in the late 1970s!), or ‘climate change.’

“The climate of the earth changes continually through natural cycles and has to do with the amount of activity of — are you ready for this? — the sun.

“Why do we fall prey to these environmental scares, which turn out to be hoaxes, etc. based on junk science?

“Yes, as engineers, we should strive to design systems that are efficient and cost-effective. However, to do it in the name of ‘saving the planet’ or ‘saving the environment’ or whatever other slogan is foolishness.”

To which David Sellers, PE, of Facility Dynamics Engineering in Portland, Ore., responded:

“I ran across your comment when I went to the HPAC Engineering Website to copy the link to the article and send it to some folks I work with.

“The article simply contrasts a number of different ways to provide chilled-water cooling, a utility that is in use for many campus HVAC systems, and postulates that if the ACUPCC (American College & University Presidents' Climate Commitment) intends to achieve climate neutrality, then the impact on the climate of various technologies for making chilled water might be worth considering.

“I would hope that any of us, when asked to provide counsel to a client regarding the best approach to providing new prime-mover capacity to serve an expanding chilled-water-cooling requirement, would be able to perform such an analysis and, based on the local variables, provide sound advice regarding the most cost-effective, efficient approach to solving the client's problem, including advice on the potential climate impact, if that were of interest to the client.

“For those of us without the breadth of experience or depth of knowledge necessary to do so, the article provides insight, resources, and a framework for emulating the example the author generously provides.

“With regard to CO2 as a pollutant, I believe if you explore the definition of pollution in the context of the environment, you'll find that it generally is considered to be some process or action that makes the local environment unwholesome or unfit for use.

“In human terms, CO2 concentrations above a certain threshold make the local environment unwholesome or unfit for use. Thus, I would postulate that CO2 is, in fact, a pollutant, and we humans — and, generally, all living things — are to some extent polluters, or at least ‘alterers,’ of our local environment.

“Theodore B. Taylor and Charles C. Humpstone explore this concept in their 1973 book, ‘The Restoration of the Earth.’ In it, they say, ‘Changes to their environment by non-human species are controlled or offset by other living species or by forces that are local to their origin and effects; changes by man are not.’

“Mr. Taylor and Mr. Humpstone say that while the human ability to think and apply technology allows us to survive, it also allows us to upset the balancing act that otherwise would exist. However, technology is not something we can set aside if we are going to survive; it's almost as much a part of our makeup as the genetic factors that have caused our bodies and minds to develop to their current state.

“Sort of a Catch-22 there: To survive, we need technology, but if we aren't careful with it, we can alter things beyond the natural environment's capability to deal with them, or at least deal with them in a way that allows us to survive.

“I think this is an interesting, if not scary, concept that has some validity. And if that's true, then I also think it means we have more than a technical and financial responsibility as we apply technology. I think that is the point William J. Coad makes in his article ‘Energy Conservation Is an Ethic’ (ASHRAE Journal, July 2000), in which he says: ‘(We need) to practice our profession with an emphasis upon our responsibility to protect the long-range interests of the society we serve and, specifically, to incorporate the ethics of energy conservation and environmental preservation in everything we do.’

“Given the preceding, I've concluded that the activities of humans may have contributed to global warming. Some of this simply is based on observations I have made. I travel a lot for my job and, as a result, spend a lot of time looking out of airplane windows. As I do that, I often am struck that there seldom is a point that clusters of light, with dots of light moving between them, cannot be seen. Given the fossil-fuel consumption (among other things) driving those lights (which represent a fraction of what the fossil fuels actually are driving), it seems impossible to believe the activities of humans are not impacting the environment. Whether those activities triggered global warming or simply have contributed to it is up for debate.

“Another interesting thing you notice at that altitude is how incredibly thin our atmosphere is. When discussing the view of the earth from the moon, all astronauts in one way or another comment on how beautiful, yet fragile, the planet appears.

“For me, all of this — combined with lessons from mentors who concerned themselves with environmental issues; parents and grandparents who farmed and, as a result, had a strong grasp of the interplay between humans and the earth; and spiritual teachers and religious leaders who believe we all are part of something much bigger than any of us — leads me to live and work in a way mindful of the impacts my activities might have on the environment — that is to say on all things because we all are connected.

“I'm truly thankful for your assertion that, ‘As engineers, we should strive to design systems that are efficient and cost-effective.’ In practicing what you preach, you do the profession an honor. And who knows, if it turns out there is something to all of this planet-saving ‘foolishness,’ your practice may have, in some small way, reduced greenhouse-gas emissions and had an impact on global warming.”