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To know how much electricity you use each day, you need to check the energy consumption of all the electrical appliances you use regularly. Here’s a simple process you can follow:

1. Make a List of Appliances

Start by making a list of all the electrical appliances you use in a day. This could be:

• Lights
• Refrigerator
• Fans
• Air conditioners
• Computers or TVs
• Washing machines
• Microwave
• And more!

2. Check the Power Rating of Each Appliance

Each appliance should have a power rating (usually measured in watts, W). You can usually find this on the appliance label or in the user manual.

If the label lists amps (A) instead of watts, you can use this simple formula to find the wattage:Wattage (W)=Voltage (V)×Current (A)\text{Wattage (W)} = \text{Voltage (V)} \times \text{Current (A)}Wattage (W)=Voltage (V)×Current (A)

In most homes, the voltage is either 120V (e.g., in the US) or 230V (in many other countries).

3. Estimate How Long You Use Each Appliance

Now, think about how many hours you use each appliance on an average day. For example:

• A light bulb might be on for 5 hours.
• Your refrigerator could be running all day, but it cycles on and off, so we’ll consider its average usage.
• The air conditioner could be on for 8 hours.

4. Calculate Energy Usage for Each Appliance

Once you know the power rating and the usage time, you can calculate the energy each appliance uses per day. Here’s how you do it:

Use this formula:Energy (kWh)=Wattage (W)×Hours of Use (h)1000\text{Energy (kWh)} = \frac{\text{Wattage (W)} \times \text{Hours of Use (h)}}{1000}Energy (kWh)=1000Wattage (W)×Hours of Use (h)​

The reason we divide by 1000 is to convert from watt-hours to kilowatt-hours (kWh), the standard unit of energy.

Example:

Let’s go through some examples.

• A 100-watt light bulb used for 5 hours per day:

Energy=100 W×5 h1000=0.5 kWh\text{Energy} = \frac{100 \, W \times 5 \, h}{1000} = 0.5 \, kWhEnergy=1000100W×5h​=0.5kWh

So, that light bulb uses 0.5 kWh of electricity each day.

• A 500-watt refrigerator running for 24 hours (it cycles on and off, but let’s assume it runs 24/7):

Energy=500 W×24 h1000=12 kWh\text{Energy} = \frac{500 \, W \times 24 \, h}{1000} = 12 \, kWhEnergy=1000500W×24h​=12kWh

The refrigerator uses 12 kWh each day.

• A 150-watt TV used for 4 hours:

Energy=150 W×4 h1000=0.6 kWh\text{Energy} = \frac{150 \, W \times 4 \, h}{1000} = 0.6 \, kWhEnergy=1000150W×4h​=0.6kWh

So the TV uses 0.6 kWh per day.

5. Add It All Up

Now, just add up the energy usage for all your appliances to get your total daily electricity usage in kWh.

Let’s assume you have:

• Light bulb: 0.5 kWh
• Refrigerator: 12 kWh
• TV: 0.6 kWh
• Washing machine: 1 kWh (for a 1-hour wash with a 1000W machine)

Total daily usage = 0.5 kWh + 12 kWh + 0.6 kWh + 1 kWh = 14.1 kWh.

So, in this example, your total daily electricity usage is 14.1 kWh.

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Why This Matters

• Estimate Solar Panel Needs: By knowing your daily energy usage, you can figure out how much solar power you need to meet your needs.
• Reduce Your Energy Bill: You can identify which appliances are using the most electricity and look for ways to use them less or more efficiently.
• Better Budgeting: Understanding your daily consumption helps you estimate your monthly or yearly electricity costs.

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Tips to Make It Easier

• If you want to make it even easier, you could use a smart meter (if available) or an energy monitor plug. These devices will tell you exactly how much energy each appliance is using in real time.
• You can also find the energy consumption of appliances online if you don’t have the manual.