How much does it cost? The cost of
setting up the compilation of files is minimal compared to what it costs to manually
assemble the parts and pieces of data to
create a worthwhile snapshot in time. The
payback could be almost instantaneous. As
an example, you just spent $100,000 on a
lighting retrofit program, and some of the
payback was assumed to be a reduction in
cooling load. Has this occurred? What is
the effect of eliminating the heat gain during the heating season? Did the heating
costs go up? Did you meet your initial payback requirements? A trend log can assist
in answering all these questions and is well
worth the time and effort to implement.
With the data as knowledge, you will save
money on the next retrofit.
So if it is this easy, should you implement trend logging? You betcha! Knowledge is power. The more knowledge you
have, the better you can react to any situation. You may even start a new trend.
Column also available at
www.districtenergy.org/de_magazine.htm
Steve Tredinnick, P.E., is a
project engineer for Affiliated
Engineers in Madison, Wis.,
with more than 20 years’
experience related to building
HVAC systems. The past 10
years of his work have been
focused on district energy
systems. Tredinnick is a graduate
of Pennsylvania State University with a degree
in architectural engineering. He is a member of
IDEA and ASHRAE and is currently vice chair of
ASHRAE TC 6. 2 District Energy. Tredinnick may
be reached at stredinnick@aeieng.com.
Radisson Riverfront Hotel Marks
Heating, Cooling Anniversaries
The Radisson Riverfront Hotel, IDEA’s hotel venue for its 2005
annual conference and trade show, this year celebrates 20 years as
a district heating customer and 10 years as a district cooling customer of District Energy St. Paul. In fact the hotel has quite a district
energy history, having been a customer of the steam district heating
system that was abandoned in favor of hot water in 1985.
The hotel uses brazed, double-wall plate-and-frame heat
exchangers for domestic hot water and shell-and-coil single-wall
heat exchangers for heating to interface with the hot water district
heating system. Numerous internal systems use the heat to meet
the hotel’s space heating, laundry and domestic hot water needs.
The hotel also uses plate-and-frame heat exchangers for
cooling since the building has internal glycol loops. Chilled water
is used exclusively for air-conditioning the space via two internal
cooling systems: one system serves guest rooms and the other
serves the meeting rooms and ballrooms.
The hotel is situated on a bluff above the Mississippi River in
the heart of downtown Saint Paul. The 22-story hotel features
475 exquisitely decorated guest rooms, suites and poolside cabanas –
a number overlooking the river. The Radisson’s revolving Carousel
Restaurant, located on the hotel’s top floor, offers diners a panoramic
view of both the city and the Mississippi. Skyway connections
give visitors indoor access to other downtown restaurants, shopping and entertainment.
The Radisson Riverfront Hotel is only 15 minutes from the
Minneapolis/St. Paul International Airport, 10 minutes from
downtown Minneapolis and 15 minutes from the Mall of America.
It is within walking distance to Xcel Energy Center (home of the
Minnesota Wild), the renowned Science Museum of Minnesota,
the Minnesota Children’s Museum, the Ordway Center for the
Performing Arts and more. Just across the bridge, riverboats offer
scenic tours of the mighty Mississippi.
With a vibrant downtown on one side and the Mississippi
River on the other, the Radisson Riverfront Hotel is the perfect
location for IDEA’s 96th Annual Conference & Trade Show.