Reading School District

System Type

Geothermal Heat Pump

Conventional VAV

Dual Duct VAV

High Efficiency Air-Cooled Chiller and Condensing Boiler VAV Terminal Unit (shut-off and parallel fan powered)

High Efficiency Air-Cooled Chiller and Condensing Boiler

Central Plant

Geothermal Field

Description

Classroom Terminal Equipment

Individual Heat Pumps

Dual Duct VAV Terminal Unit

Installed Costs ($/sq.ft.) Operating Cost ($/sq.ft./yr) Operating Energy (kBtu/sq.ft./yr)

To be determined based on schematic cost estimates

33.1

44.8

40.9

0.75 Electric

0.81

0.69

Heat Source

Natural Gas

Natural Gas

Estimated Maximum LEED points

19

2

9

Central Equipment Life Expectancy

60

25

25

Terminal Equipment Life Expectancy

15

30

30

Each zone has a separate compressor. No maintenance required for central equipment. Heat pump closets should be created in each classroom. Location of geothermal field needs to be coordinated with stormwater retention and project phasing.

Fan powered VAV terminal units have filters that require servicing.

Maintenance Concerns

Minimal

Two separate air duct systems. Need chases from rooftop equipment to each floor. Dual duct terminal units with duct connections are large.

Need chases from rooftop equipment to each floor.

Architectural Design Impact

Energy Recovery

Yes Yes

Yes No

Yes Yes

Dedicated Outdoor Air System

Humidity Control

Active humidity control

Passive humidity control

Passive humidity control

Considerable impact on emergency power system

Minor impact on emergency power equipment

Minor impact on emergency power equipment

Emergency Generator Backup

31