What is an energy meter? A complete guide

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Ever wondered what an energy meter is or what it does? If you’ve ever looked under your stairs at the strange counting device and asked yourself exactly what it’s doing and how to make the best use of it, then all your questions are about to be answered. An energy meter, sometimes known as a Watt-hour meter, is an electrical device that measures how much energy is being used by you, the consumer. By measuring how much energy you are using it can work out how much you will be charged or how long your energy top up will last.
Last update: November 2022

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You will find an energy meter installed in any home, commercial property or other building that has a mains gas or electricity supply. The energy meter keeps a record of the amount of power that is used from the grid, which is the network of power supply that connects homes and businesses. Any energy that is used in your home that comes from these mains supplies, such as lighting, central heating, appliances and more, will be logged in your meter and displayed on the device. This lets you see how much power you have been using and even allows you to work out how much your energy is costing, and whether it might be time to get in touch with our team here at papernest to switch your supplier.

What is an energy meter?

An energy meter is an electrical device that monitors how much power is being used by any building that has a mains connection. Meters are used for both gas and electricity, and are measured in kilowatt hours (kWh). You will find an energy meter in any home with a mains energy connection. There are several different types of energy meter depending on age and purpose. However, they are generally all wall mounted and housed in a box with a secure casing and some kind of display. Older meters used dials to give readings but more modern meters and smart meters use display screens to give digital readings. Energy meters record usage in kilowatt hours, which is the number of watts (or power) used in one hour. There are various types of energy meter which work and record in different ways. You can also use your energy meter to estimate your bill.

What are the types of energy meter

There are two main types of energy meter and within this a number of sub-categories. The two main energy meter types are:

  1. Electromechanical type induction meters
  2. Electronic energy meters

Within these two main types of meter there are several other distinctions that can be made about the type of meter that may be in your home. Often you just have to look at your meter to tell which kind you are dealing with but some of the differences may be more technical.

  1. The display may be either digital or analogue depending on its age
  2. The type of metering point can vary according to the distribution
  3. The end use of the meter has an impact, with different meters used for domestic, commercial and industrial properties
  4. Technical differences like single phase, three phase, high tension and accuracy can all have a bearing too

Meters are also divided into two broad payment category types too. These are credit meters, which count up your usage and then issue a bill at the end of each payment period (usually a month). The other is a prepayment meter which requires you to purchase energy in advance and provides you with a set amount of energy. energy meter

What is a smart energy meter

A smart energy meter is the same as a normal meter only it is enhanced with internet connectivity. This means it is connected to a network of energy meters via the internet and provides your supplier with up to date readings and data. This means you no longer need to read your meter and get more accurate and detailed breakdowns of your usage. They are installed by your supplier (if they offer this service) at your request.

What is the purpose of an energy meter?

The purpose of the energy meter is to keep an accurate reading of how much energy is being used. Depending on what type of meter you have, this will then either result in a bill being issued for the amount consumed or give you an accurate reading of how much prepayment energy you have left on your account. More modern smart meters still carry out these functions but use internet connectivity to automatically update your supplier about how much is being used. This means there is no need for old fashioned meter reading and should result in more accurate billing.

Energy meter reading

How does an energy meter work?

The energy meter is installed between the incoming power or gas lines from the mains and the point of distribution in your home. That means all the power and energy you consume comes through the meter. The energy meter monitors the daily use of electricity or gas and will either send a record of this to your supplier (if you have a smart meter) or display this information on a screen (a set of dials for much older meters).

How to read an energy meter

In order to read your meter correctly for a certain period, you need to know the start and end point totals. Unless you have a brand new meter, it will not be reset to 0, as it keeps a running count of the total energy used. So, you need to take a reading at the start of the period you wish to measure, as well as at the end. For example, if you want a monthly reading, write down the number on the far left dial of an old fashioned meter or on the digital display of a more modern meter. At the end of the month do the same thing. Subtract the first number from the second to give you the amount of kWhs you have used in that period.

How does it calculate energy consumption?

It measures how much power you are using by keeping a record of the number of watts you have consumed. However, to be accurate, it also needs to measure the period of time over which this energy is used. That’s why energy meters give readings in kilowatt hours. That means the number of watts used (measured in thousands for convenience) across periods of one hour. So, if your reading says you have used 24 kWh, that means you have used 1000 watts of power for a total period of 24 hours. If your washing machine runs at 500 watts, it will need to be on for two hours to have consumed one kWh. In the same way you can keep a manual count of the energy consumed using the technique above, your smart meter will also keep a running total of your energy use. It will transmit this at regular intervals to your supplier via a wireless connection to a special energy network. Old fashioned meters without a smart connection will need to be read, either through a visit from a designated meter reader or by yourself. You can speak to your supplier if you would like assistance in doing so.

How to calculate your energy bill from meter reading?

In addition, by using the above technique for finding out your usage, you can also get an idea of how much your monthly bill will be. Once you have worked out the number of kWh you have used, you can then use a copy of your latest energy bill to check the price you are paying per kWh unit. This will give you a total amount. However, it is not always that straightforward as some tariffs offer cheaper energy at certain parts of the day. There are even special meters which provide cheaper energy at night (more about these below). If this information is not displayed on your meter and you simply have a total amount, it may be difficult to get a 100% accurate reading for your bill. You also need to add in the standing charges, which is the amount you pay per day to be provided with power. These vary according to suppliers and tariff choices.

How often should my energy supplier read my meter?

According to the industry regulator, Ofgem, suppliers are required to read and inspect your meter every two years – no matter what kind of meter you have. However, some suppliers will make visits much more regularly. Bills you receive between these meter reading visits may be based on estimations from your previous consumption levels.

How to top up an electric or gas meter

If you have a prepayment meter, you will need to top up your energy meter in order to have power. You can do this at dedicated pay points found at the Post Office and other retailers. Some suppliers will also have an app where you can top up whenever you have an internet connection. Once you are topped up, your meter will then display your new account details and provide a total of how much energy you have left.

How to move your electric meter

If you wish to move your gas meter or electricity meter, then you are not allowed to do this yourself. In most cases, your supplier will provide this service for free or a minimal charge if you are only moving your meter a short distance – usually two metres of less. However, if you are moving your meter a larger distance you may be required to pay a certified meter installer to do the work.

A guide to moving your meter

If you want to move your meter you need to contact your supplier. They will be able to tell you if they can do the job. This depends on:

  1. Where your meter is located
  2. How far you want to move it
  3. What type of connector it has
  4. The reasons for moving it

Most suppliers have information on their website about the kind of meter relocations that they offer. Get in touch and they will give you a price and arrange a time to do it. Remember, only your current supplier can move your meter. If you want another supplier to move your meter, you will need to first switch your supply.

How to switch to a smart energy meter

You may have decided the time is right to switch to a smart meter. First you need to check that your supplier offers smart meters as part of their package. If they do you should get in touch to arrange installation. If they do not then you may need to switch to a supplier that does offer smart meters.

How to switch from a prepayment meter

Similarly, if you have a prepayment meter and wish to switch to a credit meter, you should get in touch with your supplier. They can arrange a date to install a new meter.

The difference between MPAN and MPRN

If you are not sure which of your meters is for which service there is an easy way to tell them apart. One will say MAPN which stands for Meter Point Administration Number and refers to electricity. The other will say MPRN and stands for Meter Point Registration Number and monitors gas usage. Each will have a personal number which refers only to your specific meter. You may be required to provide or check these with a supplier over the phone when taking a reading.

How can I test my energy meter?

Meters are generally accurate and give clear readings but faults do occur. If you suspect you have a fault or have a bill that does not reflect your usage, then contact your supplier. They will be able to conduct a test to see if your meter is working. However, you can also run a quick test yourself. Find an appliance in the home where you know the power rating, for example 500 watts. Take a meter reading then run this for exactly one hour. At the end of the hour period your reading should have increased by 1kWh.

Why are my meter readings so high?

There are a few reasons why your meter reading might be high. One, although it is unlikely, is that your meter is faulty and giving inaccurate readings. Your meter will be checked by your supplier at least every two years and faults are rare. Another reason is that you have upgraded or added appliances to your home. Many new appliances, while being more efficient, actually consume small amounts of energy at all times. This is known as vampire energy, with appliances being on standby at all times being a major drain. Conversely, using old and outdated appliances can also consume high levels of energy, as can poor insulation. Make sure things are turned off, windows closed when the heating is on and you have made your house as airtight as possible. Think about using energy in a more sustainable way. It might also be simply time to switch your supplier and get a better deal. Give us a call here at Papernest to find out more.

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What is an energy meter?

An energy meter is an electronic counting device that monitors how much power you are using in your home. It is placed between the incoming energy source and the distribution point of your home energy network. It gives an accurate reading of how much power you have been using, allowing accurate bills to be sent at the end of billing periods.

How do energy meters measure consumption?

Energy meters measure consumption using kilowatt hours. This is a unit that counts when 1000 watts of power have been used for one hour. If you have a dishwasher that runs at 500 watts and it is one for two hours, then you have used one kilowatt hour.

Can I work out my energy bill from my meter?

You can. You need to take two readings, one at the beginning of the month and one at the end. This then tells you how many kWhs you have used. By checking your bill to see how much you are paying per kWh, you can then get an idea of how much your bill will be when you add in standing charges.

How does a prepaid energy meter work?

Prepayment meters, unlike credit meters, need to be topped up with funds in advance before releasing power to your home. Credit meters are when you pay for your energy after the fact based on your consumption. Prepayment meters can be topped up at various pay points in retailers as well as using online apps. They are often used in rented accommodation and people wanting to stick to a tight energy budget.

Updated on 11 Nov, 2022

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