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LED Project

Currently, Bryn Mawr College Facilities Department is working on a project of replacing light bulbs in dorms and other major buildings with LED lights to conserve energy and reduce carbon emission. Installation of LED lights had taken place in Denbigh Hall during summer 2008. Several other kinds of LED lights are now being tested in Campus Center, Radnor Hall, and the exterior of Pembroke East.

Rhys Carpenter Library

Rhys Carpenter Library

For the first and second week of research, we are working on the case for Rhys Carpenter Library — doing initial counts, return on investment (ROI) and Carbon Emission Reduction calculations. Hopefully by the end of our research term, we will be able to finish several other buildings hence we could run a comparative analysis. We checked model numbers while doing initial counts and referred to product specification as to have a more precise calculation. Similar procedures also apply to LED replacements, so that they could fall into the correct categories in the SmartIdeas prescription.

Here are the ROI calculations for Carpenter Library with and without the SmartIdeas Incentives.

For Carbon Footprints Reduction, click here.

Below is a table showing all results for Carpenter.

Carpenter Library

T8

U-shaped T8

PAR 38

Counts

527

226

50

Watts

32

32

100

Lifespan(hrs)

6,000

20,000

4,000

LED Replacement

LED 6114

LED-UTube

LED 1666

LED Price ($)

$85.75

$100

$82.15

Initial Investment (Labor & Material)

$49375.67

$24248.00

$4837.00

LED Watts

16

15

10

LED Lifespan(hrs)

50,000

50,000

50,000

Return on Energy Saving/Yr ($)

$3041.21

$1385.70

$1623.03

Return on Labor Cost/Yr ($)

$2951.20

$1265.60

$280.00

Total Return/Yr ($)

$5992.41

$2651.30

$1903.03

SmartIdeas Incentive ($)

$11857.50

$0.00

$750.00

Total Cost – Incentive ($)

$37518.16

$24248.00

$4087.00

Years to Breakeven

6.26

9.15

1.89

Carbon Emission Reduction/Yr (lbs)

4504.770353

2052.576814

2404.111313

GATEWAY, HELFARIAN, CARTREF

During the third and fourth weeks of research, we worked on the analysis of three buildings, Benham Gateway, Helfarian, and Cartref — doing initial counts, return on investment (ROI) and Carbon Emission Reduction calculations.

Here are the ROI calculations

For Carbon Footprints Reduction, click here.

FOR MORE BUILDINGS, SEE OUR RESEARCH JOURNAL!!!!


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Continuing the Discussion

  1. BMC Sustainability » Rhys Carpenter Library linked to this post on May 24, 2010

    […] For complete ROI formula, breakdown of each section, and details on Carbon emission reduction calculations, please click here. […]