University Ridge at
East Stroudsburg University
Matthew Carr
Spring 2007
Mechanical Option
Faculty Advisor: Dr. Freihaut
University Ridge at
East Stroudsburg University
Outline
Project Team
Building Information
Existing Mechanical Conditions
Redesign Goals
Mechanical Redesign
Redesign Analysis
Photovoltaic Breadth
Recommendations & Conclusions
Acknowledgements
Questions
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Project Team
Building Name:
University Ridge at East Stroudsburg
Building Owner:
University Properties Inc.
Building Developer:
Capstone Development Corp.
Architect:
Design Collective Inc.
Engineers:
Greenman-Pedersen Inc.
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Building Information
Location:
East Stroudsburg, PA on the East Stroudsburg University
Campus
Building Statistics:
Student Residence – Apartments
541 Beds – 136 Units
3 stories plus an occupied walk in basement
140,000 square feet – 10 Buildings
Development Cost: $27,200,000
Construction Cost: $15,750,000
Construction: August 2004 – August 2005
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Building Information
Building Site Plan:
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Existing Mechanical
Conditions
Heating System:
Hot water coil duct furnaces – Dedicated unit for each housing unit
Hot water supplied by a dedicated residential hot water heater
Electric unit heaters for unoccupied spaces.
Cooling System:
Chilled water coil duct furnaces – Dedicated unit for each housing unit
Chilled water supplied by a dedicated DX condensing unit
General:
Individual exhaust fans for bathrooms
Naturally ventilated living spaces to decrease load
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Redesign Goals
Combined Heat & Power Goals:
Reduce emissions while increasing overall fuel usage
for producing power
Provide space heating using waste heat from power
production
Provide chilled water with absorption cooling which
utilizes the waste heat from power production
Reduce fossil fuel usage
Determine feasibility of a payback period
Decrease annual operating cost
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Mechanical Redesign
What is Combined Heat and Power?
Electricity is generated on site by a prime mover
Waste heat is used for the heating and cooling processes
CHP typically runs at a lower operating cost but has a higher first cost
Load leveling increases operating efficiency
Main Components of Combined Heat and Power?
Prime Movers (gas turbines, reciprocating engines, etc.)
Absorption Chillers
Chilled Water Storage Tanks
Cooling Towers
Pumps and Distribution
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Mechanical Redesign
Spark Gap Feasibility Analysis?
Determination of difference between natural gas and electricity cost:
Natural Gas:
$1.33/therm
Electricity:
$0.0919/kWh
$26.94 - $13.30 = $13.64
A spark gap of $12.00 or greater is usually considered a viable solution.
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Mechanical Redesign
Determination of Prime Mover
Building electric demand load of 366 kW
Building heating load of 775 MBH
Building cooling load of 177 tons
Prime Movers Considered
Reciprocating Engines
Fuel Cells
Natural Gas Turbines
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Mechanical Redesign
Natural Gas Micro-turbine & Absorption Chiller Selection
Integrated micro-turbine and chiller/heater power system
Comes as packaged unit integrated with controls
Unit made up of 60 kW micro-turbines
Heat exchanger contained within the absorption chiller
Good under part load condition as micro-turbines can be
selectively turned off or on as needed
Fewer moving parts than internal combustion engines
Typically reduced emissions over internal combustion
engines
Integrated inverter optimizes efficiency
Integrated system allows for reduced installation cost.
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Mechanical Redesign
Integrated Micro-turbine Chiller/Heater System Specs:
4 – 60 kWe Micro-turbines
Net Power
Output
(kWe)
Fuel
Consumptio
n LHV (MBH)
Cooling
Output
(Tons)
Heating
Output
(MBH)
Flow Rate
(gpm)
Net System
Efficiency
ISO Day (59F)
227
3,000
142
1,282
297
84%
Design
CoolingDay (95F)
193
2,800
124
-
297
76%
Heating Day (32F)
231
2,800
-
1,100
297
68%
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Mechanical Redesign
Heat Recovery:
Waste heat from turbines recovered in the absorption chiller
High temperature generator and evaporator sections used as heat
exchanger
Production of 140°F water used for hot water heating in the fan coil
units.
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Mechanical Redesign
Double-effect Absorption Chiller:
Waste heat used to regenerate LiBr solution which acts as the
condenser which is usually electrically powered
Cooling tower needed for heat removal from the condenser
Use of LiBr and water eliminates for ozone depleting refrigerants
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Mechanical Redesign
Existing Installation Example:
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Mechanical Redesign
Chilled Water Storage:
Chilled water storage used to level and shift the cooling load to
increase efficiency
Allows for chiller size reduction
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Redesign Analysis
Energy Analysis:
Energy analysis was done using RETscreen CHP energy analysis
program
Analysis run using UTC Pure Comfort system, the determined cost data
and calculated loads
The following table shows the operating capacity of the system
Electricity
delivered to
load
Electricity
exported to
grid
Remaining
electricity
required
Heat
recovered
Remaining
heat
required
Power
system fuel
Operating
profit (loss)
Efficiency
Operating
strategy
MWh
MWh
MWh
million Btu
million Btu
million Btu
$
%
Full power
capacity
output
2,102
1
509
7,100
206
27,423
175,052
52.0%
Power load
following
2,102
0
509
7,095
211
27,413
174,987
52.0%
Heating load
following
1,030
1
1,581
5,955
1,350
13,442
59,762
70.5%
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Redesign Analysis
Monthly System Characteristics:
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Redesign Analysis
Existing Cost:
Existing mechanical system cost determined to be $2.1 million dollars
as built
Estimated First Cost:
Equipment
Prime Mover
Size
Installed Cost
240 kW
Quantity
$2,500
Total
240
$600,000
Cooling Tower
205 (tons)
$95.50 (per ton)
2
$39,155
Absorption Chiller
142 (tons)
$1197 (per ton)
1
$170,000
-
$17,000
-
$17,000
Expansion tank
2 - 266 (gal)
$3,325
2
$6,650
4" Service pad
2835 s.f.
35 (c.y.)
$6,300
Storage Tank
$180 (per c.y.)
Chilled Water Pumps
1 1/2" 100gpm
$3,875
8
$31,000
Cooling Water Pumps
3" 385 gpm
$6,175
2
$12,350
-
$264,332
Piping
-
-
$1,146,787
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Redesign Analysis
System Payback:
System payback was also calculated using RETscreen CHP energy
analysis program
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Redesign Analysis
System Payback:
Cumulative cash flows graph
Year
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Redesign Analysis
Emissions Analysis:
The following tables were generated using manufacturers data and the
national grid average for emissions
lbm Pollutant /kWh Prime Mover
Fuel
Particulates
SO2/
kWh
Nat.
Gas.
2.37E-04
n/a
lbm Pollutantj /kWh U.S.
NOx/kWh
CO/kWh
2.15E-04
8.60E-05
Fuel
% Mix U.S.
Particulates
SO2/kWh
NOx/kWh
CO2/kWh
Coal
55.7
6.13E-04
7.12E-03
4.13E-03
1.20E+00
Oil
2.8
3.03E-05
4.24E-04
7.78E-05
5.81E-02
Nat. Gas
9.3
0.00E+00
1.26E-06
2.36E-04
1.25E-01
Nuclear
22.8
0.00E+00
0.00E+00
0.00E+00
0.00E+00
Hydro/Wind
9.4
0.00E+00
0.00E+00
0.00E+00
0.00E+00
Totals
100.0
6.43E-04
7.54E-03
4.44E-03
1.38E+00
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Redesign Analysis
Emissions Analysis:
RETscreen CHP energy analysis program was also determined the GHG
emissions produced by the proposed system and compared to
the base case
Combined cooling,
heating & power
project
Years of
occurrenc
e
Base case
GHG
emission
Proposed
case
GHG
emission
yr
tCO2
tCO2
2,282
2,046
1 to 2
Net annual GHG emission reduction
236
tCO2
GHG
credits
transactio
n fee
Net
annual
GHG
emission
reduction
tCO2
%
tCO2
236
is
equivalent
to
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Gross
annual
GHG
emission
reduction
48.0
0%
236
Cars & light trucks not used
Matthew Carr
Spring 2007
Mechanical Option
Photovoltaic Breadth
Photovoltaic Basis:
Photovoltaic shingles built into sloped roof
Able to offset peak power loads during the day reducing the grid
dependency of the CHP system
Drawbacks: expensive, inefficient, minimal architectural effect
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Photovoltaic Breadth
PV Capacity and Cost Analysis:
The analysis of the PV cells was done using RETscreen PV
PV Cost:
$557,476
Energy Delivered:
49 MWh/yr
Simple Payback:
12.4 yrs.
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Recommendations &
Conclusions
Conclusion:
Increased total energy and fuel efficiency
Lowered operating cost
Higher initial cost
Lower emissions and greenhouse gases
Recommendations:
Given the previously determined data and facts, it is
recommended that this CHP tri-generation system be
implemented as it has a payback timeframe for that of a
university and would save money and energy use in the
long run
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Acknowledgements
Thanks to the Following:
Architectural Engineering Faculty and Staff
Faculty Advisor: Dr. Freihaut
The AE Class of 2007
My Friends
The GPI Mechanical Department
My Family
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option
Questions
Penn State Architectural Engineering Thesis
University Ridge at East Stroudsburg
Matthew Carr
Spring 2007
Mechanical Option