Making the Grade in Energy Efficiency
June 2, 2008
This year, I have challenged our members to be more innovative in our thinking and more elegant with our solutions to improve actual building performance. I had the opportunity to visit several innovative K-12 school projects in Wausau, Wisconsin, last week.
The Wausau School District has worked with one of our ASHRAE members, Mark Lentz, from Wisconsin. Mr. Lentz has spent years developing an innovative method to provide HVAC with substantially less energy. His strategy has been conceived to address the twin challenges of providing a high quality indoor environment while substantially reducing the system operational annual energy use.
The system uses a variable volume double duct configuration that utilizes only 100% outside air. The system uses a combination of direct/indirect evaporative cooling with energy recovery from the building exhaust system. These schools I visited are supplied with 100% outside air whenever they are in operation. The faculty and staff have noticed the improved indoor air quality provided and the school district has realized substantial energy savings when compared to their other schools.
The Wausau School District installed the first such system approximately five years ago and has the metered energy data to show the results. They now have these systems installed in both new and existing schools with similar results. It is also worth noting that these systems have been installed without a premium first cost. I also realized on my visit the importance of building owners who are willing to consider these alternative strategies. In this case the Direct of Physical Plant for the school district, Dennis Wald, had seen this system used in another project and was interested in having his facilities benefit from its implementation.
The ASHRAE Advanced Energy Design Guide for K-12 School Buildings also helps identify building envelope, lighting and mechanical systems to improve the learning environment while reducing energy consumption. The book is available for free download at www.ashrae.org/freeaedg.
These innovative systems at Wausau School District are a great example of an ASHRAE member who has utilized fundamental psychometrics to develop an innovative method to address both the IAQ and energy efficiency challenge.
Are you willing to be more innovative and creative in developing elegant alternatives that can produce similar results?
The lack of enough fresh air and poorly designed older HVAC’s in sealed-buildings, especially schools, built from the 1970’s forward, are contributors to the development of dampness, causing overgrowth of mold and bacteria, resulting in significant illnesses for school occupants. It is encouraging to see that careful consideration of these problems is leading to conditions that will produce healthier buildings. We must make drastic changes or lose the health of the nation.
Thank you, ASHRAE, for highlighting Mr. Lentz’s fine work!
Thank you to Mark Lentz.
He has been doing a very fine job providing the State of Wisconsin and our Nation concerning knowledge of how are buildings can be healthy.
It is nice to see such a professional provide us with a system that will be healthy in our public schools and how the public is always welcome to view these healthy schools.
We all know what significant health problems can occur within a building lacking proper ventilation.
Thank you ASHRAE and Thank you Mark Lentz.
As the energy manager for a large metropolitan Milwaukee school district I can vouch for the Mark Lentz air handling system. Our school district installed Mr. Lentz’s designed ventilation system in our two high school pools, locker rooms and fieldhouse/gym areas in 2007. After a very steep (and painful) learning curve on the mechanical contractor and controls end, we’ve finally ironed out the wrinkles and are finding so many hidden advantages to this system besides the energy savings and improved indoor air quality that I’m just amazed it hasn’t been done before.
For example, we are considering an option to fully sanitize our locker rooms
with a fogging process injected in the HVAC system that would require a 15 minute dwell and 45 minute purge cycle should we ever have the need to sanitize those areas. The peace of mind with having this option is critical but would not be possible without the Lentz system already in place.
Health care facilities take heed! Better health, energy reduction and cost savings can coexist all in one package with this system.