Calculating Energy Cost for an Industrial Refrigerator

Understanding the cost of operating electrical appliances like an industrial refrigerator is crucial for managing expenses. This calculation involves determining the total energy consumed over a period and multiplying it by the cost per unit of energy.

Steps to Calculate Energy Cost

1. Determine the power consumption of the appliance in kilowatts (kW).
2. Calculate the total operating time in hours over the specified period.
3. Calculate the total energy consumed in kilowatt-hours (kWh). Energy is the product of power and time: \(\text{Energy} = \text{Power} \times \text{Time}\).
4. Multiply the total energy consumed (in kWh) by the cost per kWh to find the total energy cost.

Applying the Steps to the Industrial Refrigerator Problem

Let's apply these steps to find the energy cost for the industrial refrigerator described in the question.

• Power consumption of the industrial refrigerator = 5 kW
• Operating hours per day = 10 hours
• Number of days = 30 days
• Cost per kWh = Rs. 4

Step 1: Calculate Total Operating Time

The refrigerator operates for 10 hours each day for 30 days.

Total operating time = Operating hours per day \(\times\) Number of days

Total operating time = \(10 \text{ hours/day} \times 30 \text{ days} = 300 \text{ hours}\)

Step 2: Calculate Total Energy Consumed

Now we calculate the total energy consumed using the power and the total operating time.

Total energy consumed = Power \(\times\) Total operating time

Total energy consumed = \(5 \text{ kW} \times 300 \text{ hours} = 1500 \text{ kWh}\)

Step 3: Calculate Total Energy Cost

Finally, we calculate the total cost by multiplying the total energy consumed by the cost per kWh.

Total Energy Cost = Total energy consumed \(\times\) Cost per kWh

Total Energy Cost = \(1500 \text{ kWh} \times \text{Rs. } 4/\text{kWh} = \text{Rs. } 6000\)

So, the cost of energy to operate the industrial refrigerator will be Rs. 6,000.

Revision Table: Energy Cost Calculation

Here’s a quick review of the calculation process for finding the cost of energy for an appliance.

Additional Information: Understanding kW and kWh

It's helpful to understand the difference between kW and kWh when dealing with energy consumption and cost.

• kW (kilowatt): This is a unit of power. Power is the rate at which energy is used or transferred. A 5 kW appliance uses energy at a rate of 5 kilowatts.
• kWh (kilowatt-hour): This is a unit of energy. It represents the amount of energy consumed if a 1-kilowatt appliance runs for 1 hour. It is the standard unit used by electricity providers to measure consumption and calculate bills. If a 5 kW appliance runs for 1 hour, it consumes 5 kWh of energy. If it runs for 10 hours, it consumes \(5 \text{ kW} \times 10 \text{ hours} = 50 \text{ kWh}\).

The cost of electricity is typically based on the total energy consumed, measured in kWh.