What does kWh mean?
You might see the term kWh when researching for your solar panel installation. If you’re unsure what it means or how it relates to your solar panels, don’t worry because we’re here to give you a breakdown.
- A kWh is made up of numerical values that measure how much electricity an appliance uses. The ‘kilo’ refers to the amount of electricity used, the ‘watt’ is the unit of power being used, and the ‘hour’ is how much electricity is used per hour.
So, what is the meaning of kWh?
In simple terms, each letter stands for a numerical value that measures how much electricity an appliance uses.
Kilo: The amount of electricity used.
Watt: The unit of power being used.
Hour: The measurement of electricity usage per hour.
What is a kilowatt and how does it differentiate from a kiloWatt-hour?
kW (kiloWatt) measures the power an appliance needs, while kWh (kiloWatt-hour) goes further and tells you how much energy is being used over a period of time. As a guideline, 1 kW equals 1,000 Watts.
What’s the average rate of kWh?
Each appliance needs a different amount of power, which you’ll find by checking the appliance or its manual. For example, a gaming console may use 200 Watts while a dishwasher uses 1200 Watts.
And figuring out how much 1 kWh costs depends on the supplier and year - that’s why it’s important to investigate how much electric we use in our homes. This also proves why solar panels are so beneficial as you’re using your own power to run your appliances.
How many kWhs does a house use?
On average, a UK home can use 2,700–3,100 kWh per year, equating to 225–260 kWh per month.
How do I work out how much money I am spending on electricity?
Because of the fluctuation in costs and the different energy rates from providers, we can’t give you an exact number of what you’re spending. But we can give you the equation to work it out for yourself:
Appliance Wattage x current electricity price x average usage time = daily cost
Appliance Wattage: the wattage of the household item in question is formatted as shown.
240 Watts = 0.24
2,000 Watts = 2
1,400 Watts = 1.4
Electricity price: as of writing this, it’s at 24.50p, formatted as 0.245
Average usage time: the amount of time the appliance is being used per day, formatted as shown.
8 hours a day = 8
14 hours a day = 14
30 minutes a day = 0.5
Example:
Appliance: Air fryer (1,500 Watts = 1.5)
Electricity price: 0.245
Average usage time: 30 minutes a day (0.5)
1.5 x 0.245 x 0.5 = £0.37 a day
In this example, using this air fryer costs around £11.10 a month and £135.05 a year.
Remember that the cost of electricity will be determined by your provider who base their figures on how much they pay for it at a wholesale price. The average cost will also depend on the current state of the world. If there’s a crisis, suppliers will charge a similar price. If there’s stability, suppliers fluctuate their prices to gain a competitive edge.
How to calculate kWh
To calculate kilowatt-hours (kWh), you then need to convert the appliance power from watts to kilowatts by dividing it by 1000 and then multiply the kW by the number of hours used. The formula is:
kWh = Power (kW) × Time (hours)
What’s an energy cap?
Ofgem is a non-ministerial government department responsible for regulating the UK’s electricity and downstream natural gas markets. They’ve capped the kWh rate at 24.50p. This means energy providers can’t charge more than this for their electricity.
Ofgem base this on how much providers pay for their supply at the wholesale price, how much it costs them to maintain and invest in the networks that actually supply our homes with energy, operating costs for the supplier (such as wages, company vehicles, etc.), and VAT which is currently at 5%.
Ofgem looks at all of this as well as the average use of energy in a home. They then set the cap limit, but this only impacts the kWh not your bill. The more energy you use, the more your bill will be.
How much kWh should I be using?
Each household uses a different amount of energy based on their needs, the number of people living there and the appliances in their home. Ofgem estimates that the average home uses 2,900 kWh of electricity. Having a smart meter in your home can be really beneficial for monitoring the amount of electricity you’re using too.
How do smart meters measure and display kWh usage?
Your smart meter will measure the voltage and current and then display it, either at the meter or on your in-home display (IHD), showcasing the total kWh you’ve used, before sending it automatically to your energy supplier.
What can I do to save on energy costs?
There are loads of small things you can do around your home to help save on energy costs. While some may not seem that impactful, over time the amount of energy you save will build up and you’ll see the difference. Reducing your electricity demands by turning off lights or buying energy-efficient devices is a great way to lower your energy usage, but there’s another powerful way for you to save.
The term ‘loading’ refers to the use of several power-hungry appliances at once. If you use your cooker, dishwasher and electric heating all at once, this’ll cause a big surge in power being directed to your home, therefore costing you more. Being aware of this and planning when you use certain appliances can save you a lot.
If you’re an owner of solar panels, loading can have an impact on them too as it’ll either drain the battery or overload the panels potentially causing some damage.
How do solar panels affect this?
Having solar panels will be a huge advantage to any homeowner as you’ll be using your ‘own’ energy instead of relying on a provider, all while potentially being paid by an energy supplier for surplus electricity. For reference, the solar panel kWh rate is around 1.5 a day.
Learn more about the kWh that solar panels can produce in your article on the advantages and disadvantages of solar panels.
