Refrigerator Energy

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Velit semper dolor!!

GG Refrigerator Annual Energy Usage and Control Optimization

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Goals of Experiment

• Verify the amount of energy used on an annual basis through measurement.
• Reduce the amount of condensation collecting at the bottom of the fridge.
• Measure the temperature gradient across the interior of the fridge (profile).

Decisions to be made from Experiment

• Determine optimum temperature setpoint and possibly thermocouple location.
• Determine if annual energy usage being reported needs to be adjusted.
• Determine if condensation is normal or if it needs to be further addressed (racks in bottom, desiccant, cleaning schedule, waterproof container area, etc.).

Expected Outcomes

• Reduce the amount of condensate and/or mitigate impact on stored items.
• Reduce amount of temperature stratification in the fridge interior.
• Able to more accurately predict annual cost of running the refrigerator.

Methodology

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General

• Kill A Watt meter resets itself when unplugged (does not retain data when unplugged).
• Plug in fridge, noting date and time.
• Deploy data loggers.
• Purchase rice.
• Remove any existing condensate in fridge.
• Make controlled openings and place in bottom of fridge.
• Run experiment for two weeks in heating season and two weeks in cooling season.
• Complete documentation, analysis, and report results.

Process Measurements

• Measure actual kWh using plug-in meter over time.
• Measure temperature profile in interior.
• Measure condensate developed weighing bag of open rice before and after period of time.

Resources Required

• Kill A Watt meter
• Data Loggers for temperature
• Bag of rice
• Food scale or postal scale to weigh rice

Planning

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Participants

• Peggy
• Laurie
• Helen
• Tom
• Kirsten
• Mr. No Name

Collaboration

• USL for documentation

Help Wanted

• N/A

Scheduling & Sequencing

• Winter two week period 12/9/2011 to 12/23/2011.
• Summer two week period planned for July or August of 2012.

References

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• Refrigerator Energy Workbook
• Experiment Tracker - summary of all experiments & experiment project management
• Experiment Workbook Template - report template for actual conducting of experiment
• USDA Refrigeration & Food Safety Fact Sheet

Questions

• Where did prediction of $4 per year come from? (Tree Hugger Article)
• What is our controller make/model and temperature setpoint and deadband?
• Where was/is the original temperature sensor mounted?

TO DO

• Plan / Do / Study / Act / Repeat

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