EE4 (DOE-2.1E) Water-Side Economizer Issue

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Hello,

-I am looking to simulate a water-side economizer in EE4 (DOE-2.1E) by
altering the .doe file.

-I have added the highlighted text below into the "Plant-Parameters" section
of the .doe file.

PLANT-PARAMETERS

BOILER-CONTROL = STANDBY

HW-BOILER-HIR = 1.0870

CHILLER-CONTROL = STANDBY

$ Cooling Tower $

TWR-SETPT-CTRL = FIXED

TWR-SETPT-T = 85.0

TWR-DESIGN-WETBULB = 73.0

TWR-DESIGN-APPROACH= 12.0

TWR-DESIGN-RANGE = 10.0

TWR-THROTTLE = 5

TWR-CAP-CTRL = ONE-SPEED-FAN

TWR-CELL-CTRL = MIN-CELLS

DIRECT-COOL-MODE = STRAINER-CYCLE

DC-MAX-OAT = 39.0

DC-MAX-CHILL-WTR-T = 44.0

DC-TWR-WTR-SETPT = 44.0

DIRECT-COOL-KW = 0.055

$ Condenser Water Pumps $

TWR-MOTOR-EFF = 0.917

TWR-IMPELLER-EFF = 0.790

TWR-PUMP-HEAD = 60.00

..

-After running the simulation and comparing it to previous results, there
are savings on "Space Cooling" but there is also a greater energy usage in
"Heat Reject" as show in the table below. The DOE-2 guide suggests entering
the condenser water pumping power as kW/ton but maybe I should be entering 0
for DIRECT-COOL-KW if I'm accounting for the condenser water pumps twice?
This is for a project in Nova Scotia so I think there should be savings from
turning off the chillers throughout the winter but it doesn't make sense
based on these results.

Energy Use Category

Before Change

After Change

Savings

(MBtu)

(MBtu)

(MBtu)

% Sav

Area Lights

2,252.2

2,252.2

0

0.0%

Misc. Equipment

1,629.1

1,629.1

0

0.0%

Space Heat

2,062.0

2,062.0

0

0.0%

Space Cool

615.6

475.7

140

22.7%

Heat Reject

121.5

295.6

-174

-143.3%

Pumps & Misc.

1,136.2

1,136.2

0

0.0%

Vent Fans

2,168.4

2,168.4

0

0.0%

DomHot Water

587.6

587.6

0

0.0%

TOTAL

10,572.6

10,606.8

-34

-0.3%

Best regards,

Jake R. Martell, EIT

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