A Tale of Two Houses: A Case Study in Heat Transfer
by
Frank Bowman and Brian Tande
Department of Chemical Engineering
University of North Dakota, Grand Forks, ND
by
Frank Bowman and Brian Tande
Department of Chemical Engineering
University of North Dakota, Grand Forks, ND
You are in your first semester as an engineering student at the University of North Dakota and Thanksgiving is fast approaching. Despite having serious reservations, you decide to appease your mother and attend Thanksgiving dinner at the house of your Uncle Bill. The deciding factor in your decision is the fact that your other uncle, Bubba, from Atlanta will also be there. You haven’t seen him in a few years and know that things are never dull when he is around.
As you arrive, you immediately find Bill and Bubba in a heated discussion. As it turns out, Bill has been complaining about how horrible his heating bills will be during the upcoming winter. Not to be outdone in the pity-generating department, Bubba claims that things are far worse in the South, where keeping his house cool in the summer requires much more energy.
Since you have always been known as the “smart one” in the family, Bill and Bubba naturally turn to you to settle their argument. Put your vast engineering knowledge to good use and help them settle their debate.
Which house uses more energy: Bill’s house in January or Bubba’s house in August? Why do you think so?
| Uncle Bubba’s House | Uncle Bill’s House |
|---|---|
| Atlanta, GA | Walhalla, ND |
| 2,100 square feet, 3 bedroom, 2 bath | 4,000 square feet, 4 bedroom, 3 bath |
| 2 story, aluminum siding, poorly insulated | 2 story with half-basement, wood siding |
| Built 1997, cedar deck, green asphalt shingles | Built 1925, renovated 2005, well-insulated, 3 fireplaces |
As Uncle Bubba and Uncle Bill continue to argue, you slip away to another (quieter) room. Pulling out a pad of paper, you begin to think about what factors will have an influence on how much energy is needed to heat or cool each house.
List as many factors as you can think of that will affect a house’s heating/cooling needs.
Date Posted: January 20, 2009.
Image credit: ©Neeley Spotts/iStockPhoto.
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