What is the amount of energy savings at the source (kWh/year)?
What is the amount of energy savings at the source (kWh/year)?
To calculate the amount of energy savings at the source (kWh/year), we need to compare the energy consumption of the old motor with the energy consumption of the new motor. By solving it we came to know that the amount of energy savings at the source is 7,178.35 kWh/year.
Calculating Energy Savings at the Source (kWh/year)
An electric Motor (HP-18.7, 1 HP=0.746 kW), old motor efficiency = 0.84, New motor efficiency = 0.93, hours of operation per year 4500 hrs, grid efficiency=0.35, power factor= 0.78, price of electricity = $0.08/kWh, Demand cost = $6.0/kW per month.
First, let's calculate the power consumption of the old motor:
Power consumption (kW) = HP * 0.746 kW/HP = 18.7 * 0.746 kW/HP = 13.927 kW
Next, we need to calculate the energy consumption of the old motor per hour:
Energy consumption (kWh) = Power consumption (kW) * hours of operation per year = 13.927 kW * 4500 hrs = 62,671.5 kWh/year
Since the old motor has an efficiency of 0.84, we can calculate the energy consumption at the source:
Energy consumption at the source (kWh/year) = Energy consumption (kWh) / efficiency = 62,671.5 kWh/year / 0.84 = 74,630.95 kWh/year
Now, let's calculate the power consumption of the new motor:
Power consumption (kW) = HP * 0.746 kW/HP = 18.7 * 0.746 kW/HP = 13.927 kW
Next, we need to calculate the energy consumption of the new motor per hour:
Energy consumption (kWh) = Power consumption (kW) * hours of operation per year = 13.927 kW * 4500 hrs = 62,671.5 kWh/year
Since the new motor has an efficiency of 0.93, we can calculate the energy consumption at the source:
Energy consumption at the source (kWh/year) = Energy consumption (kWh) / efficiency = 62,671.5 kWh/year / 0.93 = 67,452.6 kWh/year
To calculate the energy savings at the source, we subtract the energy consumption of the new motor from the energy consumption of the old motor:
Energy savings at the source (kWh/year) = Energy consumption at the source of the old motor - Energy consumption at the source of the new motor
Energy savings at the source (kWh/year) = 74,630.95 kWh/year - 67,452.6 kWh/year = 7,178.35 kWh/year.