Energy Usage Report for A Small Office Facility

Published by Thaweesak Aranchot, Electrical Engineer, Power Quality (Thailand) Co., Ltd.

Plan

• Measure actual usage of each load for recording a consumption. Then determine a way to reduce the usage without impacting a business efficiency
  
• Investigate the actual data comparing with Electricity bill
  

Introduction

• The energy consumption at PQT was studied to determine\how much energy was used, where it is being used, and how much it costs.
  
• Dranetz HDPQ Xplorer was setup for monitoring the usage at the main board of small office facility. EP1 was setup for determining an individual load.
  
• Then investigate an energy usage and compare with a MEA electricity bill to determine the exact energy usage and cost.
  

Loads of the Building

Figure 1:

• A main of air Conditioner is set as 25 degree.
  
• Operate continuously 9 hours.
  
• The usage is 18.8 kWh on working day
  

Figure 1

Figure 2:

A trend plot is showing a usage of two 36-watt fluorescent lamps in an hour.

18W x 12 – Consumed à 2.94 kWh/Day

36W x 4 – Consumed à 3.83 kWh/Day

Total = 6.77 kWh/Day

Figure 2

Figure 3:

• A full day used 1.29 kWh without opening a door.
  
• The usage will be 1.77 kWh per day if disturbs refrigerator operating.
  

Figure 3

Figure 4:

• Water pump usage is operated for part time.
  
• Trend plot displays an hour usage of a water pump.
  

Figure 4

Blue area is operating area

Green area is non-operating area

Figure 5:

• Office equipment: computer, router, printer, and CCTV.
  
• Illustration is a consumption of Printer
  
• Consumption is 2.35 kWh per Day
  

Figure 5

Blue area is operating area

Green area is non-operating area

A Consumption for Working Day

Load consumption of a working day in Percentage.

Average consumption is 30 kWh per day.

Figure 6:

• Trend plot is displaying a business day usage for all loads in the office.
  
• A business day usage is 31.3 kWh for per day
  

Figure 6

Figure 7:  Working day usage between middle of December to middle of January.

Figure 7 – Working day consumption

A Consumption for Non-Working day

Display a single day usage for Non- Working day (Figure 8)

• A day off usage is about 8 kWh
  
• There are kinds of load that always run all times such as CCTV, security lights, router, refrigerator.
  

 

Figure 8

Figure 9: Non-working day usage between December 2018 to January 2019

Figure 9

Total Consumption (Figure 10)

• Electricity bill displays monthly usage during December 14, 2018 and January 14, 2019.
  
• Total cost is 3,323.54 THB including vat, service charge and FT factor.
  

 

Figure 10

Solutions: How can we save cost of electricity?

Saving cost, we could reduce electricity of the main load for example:

• Air conditioner: Typically, higher temperature can be able to reduce energy usage by decreasing 10% of usage. (Table below)
  

• Clean an air filter regularly for saving 10% of the air conditioner consumption.
  
• Reduce an operation time of air conditioner for an hour that can be able to reduce 10 % of Air conditioner usage. (Credit: Analysist energy management book for small and medium business, December 2012, Ministry of Energy, Thailand.)

• Install an insulation on wall or ceiling to reduce temperature inside that allow the air conditioner work less than high temperature. (Credit: Department of Energy, United State of America.)

We could reduce electricity of load for example, Lighting:

• Fluorescent lamp can be replaced with LED lamp to reduce energy usage.
  
• A LED lamp costs 400 THB and owner will get back in 12.7 month.