measure would include checking the air flow at the diffusers to ensure that it meets
current code required flow.
ECM 9- Kitchen Hood
The existing kitchen exhaust systemhas a basic on/off operation. This results in the system
operating during times when it doesn’t need to be operating and conditioned air is
exhausted. This measure is for installing a Captive Aire unit with VFD drives on make-up air
and exhaust fans. A temperature sensor will be installed in the duct work and control
operation based on the temperature inside the duct.
ECM 10- Walk In Coolers
EEI recommends refrigeration controllers on walk-in coolers and freezers as wellas
installing electronically commutated (EC) motors on evaporator fans. A controller can
start/stop the evaporator fans when operation is unnecessary. The EC motors are 30%
more efficient thanthe standard two-pole motors. Energy savings will be realized by
reducing the runtime of the compressors and evaporator fans in addition to the reductionin
power load of the new fans. Each walk-in cooler or freezer will have a new EC fan motor and
blade installed as wellas a dedicated controller. In addition, controllers will be installed on
the freezer to optimize the operation of the electric defroster and door heater. The controller
unit senses when refrigerant has ceased flowing through the evaporator coil and controls
the fan motors. Door and frame heaters are controlled based on dew point, reducing their
run time by 95% in coolers and 60% in freezers. The controllers will reduce compressor and
evaporator runtime by up to 10%.
Calculations
Energy savings will result from both reducing the fan power and the efficient control of the
evaporator fans and door heaters. In general, EEI uses the following approach to determine
savings for this specific measure:
Cost of Existing Equipment = Existing kW x Cost per kWh x Existing Effective Full Load
Hours
Cost of Proposed Equipment Energy Savings = Existing kW x Cost per kWh x Full Load
Hours Using Control
Savings = Existing Equipment Costs- Proposed Equipment Costs
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