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Denbigh, Radnor, Haffner (and Carpenter Revisited)

It has been long since we last updated our last entry on LED project, but here we’re again. After a week of heavy work on geothermal system, we are now continuing on with what we left off for college’s energy saving! The campus in summer is quite busy, and dorms are filled with people for conferences and events. This made Katie and I looked like little strangers when we hopped into these buildings, with notepads in our arms.

With the help from Jim and several meetings in previous weeks, we’re less confused about lighting specifics as we once were during the first week — and of course, got to know more fun variations and technology standards. We also received an interesting device, a light meter, which measures the amount of illumination inside a certain radius (a.k.a. foot-candles).

Denbigh Hall

Denbigh, as many of you have noticed, has had LED installed in 2008 in all hallways, except one part of third floor which is already equipped with energy efficient T5s burning no more than 20W each.  Simply with these replacements in hallways, it reduces Denbigh’s CO2 emission by a significant amount of 4470 lbs — a reduction of approximately 50% from previous year’s number 9460 lbs!

Radnor Hall

Three buildings to the northeast of Denbigh stands Radnor, another dormitory. What we found in this building was mostly T12’s, the least energy efficient 4-ft lamp. Aside from the call for conserving energy, Radnor is in need of a higher lighting level in hallways, which was measured at 10 foot-candles (only 1/3 of the building code!) before the installation took place a week ago. Hence more LEDs are necessary to address the improvements of lighting level. Instead of having a 1 for 1 replacement such as the ones in Denbigh, the Facilities Department decided to go with a 2 LEDs for 1 T12.

Haffner Hall

Haffner has lots of recessed lighting, which are not commonly seen in other dorms, but are good candidates for LED replacements.

Finally, we paid a second visit to our old friend Carpenter to look for the 12 LEDs in level A — if you happen to be assigned to a carrel near the window, make sure you look up at least once for those cool lamps!

Detailed Calculation as follows (well, it has been abbreviated a lot from previous versions):

Rhys Carpenter

Haffner

Radnor

Denbigh

Initial Investment

$1,200

$14,300

$13,000

$8,800

Initial Investment less Incentive

$1,000

$12,700

$12,900

$7,400

Total Return/Year

$800

$6,800

$757

$2,700

CO2 Emission Reduction/Year

460 lbs

9100 lbs

3800 lbs

4400 lbs

Payback Period in Years

1.19

1.86

17.4

2.74

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