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What is the energy consumption of a refrigerator with a wattage rating of 700 Watts when it is operated for 24 hours a day?

### Step 1

To solve, use the following formula:

$$\text{EnergyConsumption=PowerConsumption}\times \text{NumberofHoursOperated}$$Where:

Energy Consumption= Watt Hours (Wh) or KiloWatt Hours (kWh)

Power Consumption= Watts (W) or kW (KiloWatts)Number of Hours Operated= Hours (h) For the example above:

Energy Consumption = 700 W x 24 h

Energy Consumption = 16800 W h

### Step 2

To convert from Wh to kWh, remember that 1kWh = 1000 Wh

To solve, set up as a ratio and use linear algebra to solve for ?.

$$\begin{array}{l}\begin{array}{ccc}\frac{1\text{}kWh}{1000\text{}Wh}& =& \frac{?kWh}{16800\text{}Wh}\\ \frac{16,800\text{}Wh\left(1\text{}kWh\right)}{1000\text{}Wh}& =& ?KWh\\ 16.8\text{}KWh& =& ?KWh\end{array}\\ \end{array}$$#### Practice Problem

Use the following link to generate a random practice problem.