study the table and compute the kwh used

How to Calculate Kilowatt-Hours (kWh Calculation)

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category: Sustainable Living

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Each and every one of our electricity bills revolve around one thing: our kWh (kilowatt-hour) usage. The problem is most of us are not exactly sure what that means. And since this measurement dictates how much we end up paying, it’s a good idea to understand what it is and how to calculate it for your home.

What is a kW and a kWh?

A “watt” is the unit used to measure quantities of power and is named after the Scottish inventor and engineer James Watt (1736-1819). A kilowatt, or kW, is equal to a thousand watts. So the number of kW is the amount of power an electrical device uses in order to run, and a kilowatt-hour (kWh) is the amount of energy that an appliance uses every hour. For example, if your electric radiator is rated at 3 kW and is left on for an hour, it would use 3 kWh of electricity.

More importantly, a kWh is the unit that electricity suppliers use to bill you for the electricity you use. They do this by either reading your usage for you, or by having you send them the reading from your meter. Usually, you are given a unit charge for your electricity; this multiplied by the number of kWh you use gives you the cost of the electricity on your bill .

How do you calculate the number of kWh used per day?

If you want to know how many kWh you use daily, simply divide your total kWh number by the number of days covered by the bill. In reality, you are not going to use exactly the same amount of electricity every day. This changes depending on how long you spend at home, what you do while you are there, the time of year, and the temperature.

You can even work out the number of kWh used by each appliance per day based on how long each is on. If you use a 3-kWh heater as an example, it will use 15 kWh of electricity if you have it on for 5 hours.

How do you calculate the number of kWh from watts?

If you want to know how many kWh an appliance uses and already know how many watts it uses, the calculation is pretty straightforward.

First, you need to convert the number of watts into kW. To do that, you divide the number of watts by 1,000. So 100 W is 0.1 kW, 60 W is 0.06 kW, and 1500 W is 1.5 kW.

To get the number of kWh, you just multiply the number of kW by the number of hours the appliance is used.

For example, a device rated at 1,500 W that’s on for 2.5 hours:

1500 ÷ 1000 = 1.5. That’s 1.5 kW. 1.5 x 2.5 = 3.75. So, a 1,500 W appliance that’s on for 2.5 hours uses 3.75 kWh.

How do I calculate kW to kWh?

Calculating kWh from kW is even easier, as you already know the number of kW for the appliance. All you need to do is multiply the kW number by the time in hours. The 3-kW heater, if used for 3.5 hours, would use (3 x 3.5) 10.5 kWh of electricity.

How many kWh is normal for a home?

In 2019, according to the U.S. Energy Information Administration, the average American home used 877 kWh of electricity every month, or 10,649 kWh each year. This varies depending on which part of the country you live in. The five states with the lowest electricity consumption include Hawaii, Maine, California, Vermont, and Rhode Island, all with about 500-600 kWh every month. The top five are Louisiana, Tennessee, Mississippi, Alabama, and North Dakota. All of these use more than 1,200 kWh every month on average.

The variation is partly climate-related, but construction regulations and the age of houses also play a part. We have become much more aware of how well-built and insulated homes are far more energy-efficient than older properties. In addition, today there are numerous ways to make homes more energy-efficient, such as using clean energy and switching to a renewable energy company .

What is the kWh usage for common household items?

The electricity consumption of home appliances varies a lot. The rules are that anything that heats or cools is likely to be a big power user and that newer models tend to be more efficient than older units.

• A furnace with a fan that uses 10 kW per hour is likely to be used for extended periods. In 12 hours, that would be 120 kWh.
• A 1,500 W portable heater will use 1.5 kW per hour. In 4 hours, it would use 6 kWh.
• A 1.5-ton heat pump without heat strips is rated at around 3 kW, so if on for 8 hours, it would use 24 kWh.
• An 8 kBtu air-conditioner uses 2.93 kWh of electricity every hour. If on for 12 hours, that is 35.16 kWh.
• An oven is around 2.3 kWh every hour.
• An old-style 15-cubic-foot refrigerator uses 150 kWh per month. By contrast, a 17-cubic-foot Energy Star refrigerator uses just 35 kWh per month.
• A 50-60” LED/4k UHD TV is about 0.071 kWh every hour, so in an evening it might use around 0.426 kWh.
• A 50” LCD TV is just 0.016 kWh, so in that same six-hour period it would use just 0.096 kWh.
• A desktop computer, when in use, uses about 0.05 kWh per hour, and in standby, this drops to 0.004 kWh.
• A laptop is 0.02-0.05 kWh per hour.
• A 300 W halogen lamp is 0.3 kWh per hour. Compare that with a 38 W LED lamp (equivalent to a 150 W incandescent), which consumes just 0.038 kWh.
• A hot wash, cold rinse wash uses about 2.3 kWh per load, and a dryer uses somewhere between 2.5-4 kWh per load.
• A vacuum cleaner uses something like 0.75 kWh per hour.
• An iron uses 1.08 kWh per hour.
• A hairdryer consumes 1.5 kWh per hour.

How do I calculate how many kWh an appliance uses?

If you want to know how to calculate kWh usage, you can usually find the electricity rating of an appliance in the instructions, on the manufacturer’s website, or on a label attached to the product. This figure will be the power consumption of the appliance. If you multiply this figure in kW by the number of hours it is on, you get the kWh.

If you are unsure of how to do this or want to check the manufacturer’s rating, you can buy a simple plug-in usage monitor that will measure kWh along with voltage, amps, cost, and so on. They are around $20-$25 and are a useful method of checking the figures are accurate.

Why is my kWh usage so high?

If you think your electricity usage is above what it should be, there are several things you should consider. If your house is old, it is likely it was built when the value of insulation was either not understood or unavailable. The construction industry has come a long way in the last 20 years, and today’s houses are like tightly sealed boxes compared to older homes.

The climate is also a major factor. If you live in an area that experiences very cold winters, super hot summers, or both, your energy usage will reflect this.

Also, older appliances really are more energy-hungry than newer ones. Not long ago, TVs in standby mode often used almost as much energy as when they were in use, today they hardly use any.

How do I reduce my energy usage?

If you want to reduce your electricity usage and lower your energy bills, there are a few things you can do:

Kilowatt-hours give you a real handle on how much electricity you consume and how you can reduce that figure. You can see which appliances are high-use items and which are more economical. When looking to buy a product, the kWh rating is important to consider.

Not only does it give you an idea of how the way you use electricity in the home can be improved, but the cost per kWh gives you a direct comparison of one electricity supplier with another.

If you’re looking for a way to reduce your carbon footprint, Inspire's 100% clean energy plan is an easy way to do your part for the planet.

Find out more about getting a clean electricity plan and learn more about the benefits of renewable energy today.

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Kilowatt hours explained: Your essential energy guide

Published 9/18/2023

Here’s what you don’t know about kilowatt hours & how it could reduce your monthly electric bill

For most of us, the first and only time we encounter kilowatt hours (kWh) is when paying our electric bills. And even then, it's often only on a need-to-know basis. We're happy having only the vaguest understanding of what a kWh actually is. The rest of the time, we remain oblivious to them.

Yet this seemingly simple unit of energy plays a far more important role in daily life than many realize. kWhs are key to understanding and reducing our energy consumption. And while they can help you get a handle on utilities, that's only part of it. 

kWhs are essential for making smart energy decisions, such as determining how many solar panels are needed when switching to solar. But what is a kWh really, and how are they different from a kilowatt (kW)? In this blog post, we take an in-depth look at the often misunderstood kWh and provide insight on how to use them to understand your energy efficiency better.

The basics: Watt's the difference between kW and kWh?

kW and kWh are often used interchangeably. And while they're similar, they measure different things. To understand the distinction between these two terms, you need to start with the most basic unit of energy: the watt. 

A watt is the measure of power 1 . In other words, watts are the rate at which energy is produced or consumed at any given moment. A good way to understand this is by considering a 100 W lightbulb 2 and a 60 W lightbulb. The 100 W lightbulb uses energy at a higher rate than the 60 W lightbulb, which is dimmer and has a lower wattage.

Watts can easily be converted to kWs: 1,000 watts is one kW. While watts and kWs are useful, they're only a snapshot of energy usage. And that's where kWhs come in. This is a measurement of energy usage over a period of time.

In other words, kWh is the measurement of the amount of power a device or appliance needs in order to run for an hour. One kilowatt-hour (1 kWh) 3 is equivalent to a power of 1 kW being used for 1 hour. kWh takes into account how many watts are used and for how long. In the case of your electric bill, you're billed for the amount of electricity consumed in kWhs. 

To simplify all this, here are some easy-to-use formulas 4 that illustrate the relationship between these different energy units:

Watts to kilowatts

watts/ 1,000 = kWs.

Example: A dishwasher of 1,200 watts could also be written as 1.2 kilowatts.

Watts to watt-hours 

watts x time in hours = watt-hours 

Example: The same dishwasher of 1,200 watts that runs for an hour will use 1,200 watt-hours.

Kilowatts to kilowatt-hours

kilowatts x time in hours = kilowatt-hours

Example: The same 1.2 kW dishwasher which runs for an hour will use 1.2 kWhs.

Calculating kWHs. How energy consumption is measured

Understanding kWhs is vital for calculating electricity usage. As an example 5 , take a 1.5 kW hair dryer. Even though it's a 1.5 kW appliance, the amount of energy it uses depends on how long it's used for. And that's where kWhs come in. If used for an hour, the hairdryer will use 1.5 kWhs of energy. But let's say you only use it for 15 minutes; it will use a quarter of the amount of energy. The same thinking applies to power-generating technologies like solar panels. If, for example, the solar panel has a power rating of 500 watts, it will, under ideal conditions, generate 0.5 kWhs in an hour and 1 kWh in two hours.

When it comes to measuring energy consumption, your utility bill might be the best and most obvious place to start. There, you should find a breakdown of your energy consumption. Most bills include a Usage or Energy Consumption section 6 , which details the kWh usage for the specific billing period. Of course, there's more you can do to further measure and understand your usage. 

This could include installing an electricity usage monitor 7 . This will help you see how many watts a specific device uses. If you want to know how many kWhs that device is using, leave the monitor plugged in for a specific period of time, like an hour, for example. Another option is the US Department of Energy's 8 appliance and electronic energy use calculator. This enables you to estimate your annual energy use and the cost of operating specific appliances. By entering the wattage of your appliance, you'll get an accurate estimate of this device's energy footprint. 

In addition, there are several formulas for calculating daily and annual appliance usage. 

Formula for calculating daily appliance usage:

(Wattage × Hours Used Per Day) ÷ 1000 = Daily Kilowatt-hour (kWh) consumption

In order to calculate the daily energy usage for an appliance, multiply its power consumption in kilowatts by the number of hours it's used per day.

Formula for calculating annual appliance usage:

Daily energy usage x number of days it's used per year = annual energy usage.

This involves multiplying the daily energy usage of an appliance by the number of days it is used in the year. The other thing to keep in mind when calculating annual usage is that all appliances have energy usage labels that provide information about their energy consumption. Typically, these energy guide labels also estimate the annual electric usage and cost for the appliance. 

The US Department of Energy 9 also provides data on how much energy different appliances use and estimates of their annual costs. Here are some examples from the US Department of Energy of common household appliances and their energy consumption:

Refrigerator: 100 to 400 watts

Air conditioner: 500 to 3000 watts

Washing machine: 500 to 1,500 watts

Laptop computer: 30 to 180 watts

LED light bulb: 5 to 20 watts

Formula for calculating the annual cost to run the appliance:

Annual energy consumption × utility rate per kWh = annual cost to run appliance 

Your energy savings start here

Energy efficiency is a good place to start when trying to reduce one's energy bills. A recent study from the International Energy Agency 10 found that in countries with energy efficiency standards and labeling (EES&L) programs, the energy efficiency of new appliances can increase by as much as two or three times. Which over a 20-year period can amount to an energy savings of as much as 10-30%. By upgrading to energy-efficient appliances with Energy Star labels, you have an opportunity not only to reduce energy consumption but also benefit from considerable energy savings . 

In addition to switching to energy-efficient appliances, it's also a good idea to unplug unused devices. When not in use, appliances still consume power, contributing to your energy consumption. The same goes for lights. It's important to turn off lights when you're not in the room. Other energy efficiency measures include insulating your home and adjusting your thermostat settings in summer and winter to conserve energy. 

Consider switching to solar

Making energy efficiency swaps isn't the only way to save money and care for the planet. By switching to solar 11 , you can save on your monthly utility bill because solar power allows you to generate your own electricity from sunlight. This means that you'll be relying less on traditional energy sources provided by utility companies, leading to reduced consumption of grid-based electricity. In many cases, excess solar energy generated during sunny periods can even be fed back into the grid, potentially earning you credits or payments from utility companies in a process known as net metering. Our expert Solar Advisors guide you through the complexities and details of solar—from understanding your energy bills, to installation and more. And each Sunrun solar system is custom designed to fit your home’s unique needs.

As the nation's #1 home solar & battery installer, we provide dedicated support from initial system design to powering on your system. Our personalized approach ensures that you make the right decisions for your home solar system, enabling you to harness the full potential of solar energy without the stress.

Take control of your energy bills

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Learning Task 3: Copy the table below on a sheet of paper. Study the table and compute the kWh used, and answer the questions below. 1. Which household consumed the most? The least? Household Previous Present kWh Used A 2. Which two households consumed the same kWh? 2150 2493 3. As a member of the household, how can you lower B 72857910 your Electric bill? C 64126755 4. Why is it important to use electricity wisely? d 4605 4938

A. Assimilation (Time Frame; Day_4 ) Learning Task 3: Copy the table below on a sheet of paper. Study the table and compute the kWh used, and answer the questionsbelow. 1. Which household consumed the most? The least? 2. Which two households consumed the same kWh? 3. As a member of the household, how can you lower your Electric bill? 4. Why is it important to use electricity wisely? PIVOT

Moscow Muled

The kombucha mule: a funky alternative to the traditional moscow mule.

Sep 08, 2017

Nothing quite compares to an icy cool Moscow Mule on a hot day. But what if you are following a diet and don’t want all the sugar typically found in ginger beer? Did you know our copper mugs are perfect for keeping any drink icy cold, and not just Moscow Mules? We recently discovered a healthy and delicious twist on our favorite cocktail that tastes incredible in our copper mugs.

We’ve been using kombucha in place of ginger beer and the tart and fizzy beverage is all the rage in health circles. You may remember mushroom tea from the 90s that sat on the counter in a large jar for months growing a mushroom like disc at the top known as a SCOBY ( which is short for " symbiotic culture of bacteria and yeast"). Many of our parents drank the tea and many of us remember that it had such a questionable smell that we couldn’t bring ourselves to try it. But now mushroom tea, or kombucha, has become mainstream and can easily be purchased from most grocery stores. And we can personally attest that it tastes delicious.

But what is kombucha anyways? Kombucha is essentially sweet black or green tea fermented with a culture of yeast and bacteria (or a SCOBY). It’s generally made with only four ingredients: tea, water, sugar, and SCOBY. While that might not sound appetizing, it tastes like carbonated iced tea with a slightly acidic finish. And what’s more, it’s incredibly good for you and might even help curb your hangover. Sign us up!

Kombucha is full of probiotics, antioxidants, and B vitamins to name a few. Probiotics are live, healthy bacteria that help create a healthy balance of organisms in your intestines. Kombucha is also said to have detoxification properties which cleanse the body and support a healthy immune style, which is why you might wake up without a hangover after indulging in this delicious beverage.

You can buy your own kombucha, ready made from the store and flavoured with delicious additions such as ginger, raspberry, or mint. For the more adventurous, you can even make your own kombucha from scratch if you have a small SCOBY to start the tea. You can sometimes find SCOBY s at farmer’s markets, Etsy, or even Craigslist (weird but true), but the easiest way would be to find a friend who already makes homemade kombucha and can give you a piece of their SCOBY .

Fun fact: did you know kombucha has a small percentage of alcohol already in it? You might have felt that slight wine buzz after downing a bottle quickly with lunch and that’s due to the small alcohol content. The alcohol content is less than 0.5% which is why it doesn’t have to be labeled on the bottle and you don’t have to be a certain age to purchase according to the rules and regulations of the Food and Drug Administration.

Once you’ve found your kombucha (for simplicity we prefer to buy our own ready made ginger kombucha) you can get started with your delicious kombucha mule recipe. If you’re serving guests that aren’t big drinkers, feel free to omit the vodka for a virgin cocktail that tastes seriously good.

Kombucha Mule

Ingredients

• 1 1/2 ounces premium vodka
• 1/2 ounce fresh lime juice
• 1/2 cup ginger kombucha
• Fresh herbs for garnish such as mint, basil or rosemary

Instructions:

• Pour vodka and lime juice into copper mugs.
• Add ice and ginger kombucha.
• Stir to combine.
• Garnish with fresh herbs.

Did You Enjoy This Article?

Thank you for reading! If you enjoyed this article, you might also like the following articles:  Best Moscow Mule with Ginger Ale and  Why You Should Only Use Moscow Mule Copper Mugs With Stainless Steel Lining

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Moscow Mule Copper Mug

Apr 15, 2021 • Posted by דירה דיסקרטית בחיפה

“Everything is very open with a clear description of the issues. It was definitely informative. Your website is extremely helpful. Many thanks for sharing!”

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