Three Phase Electricity in the UK
What is three-phase electric power?
Usually, three-phase power is a polyphase system (a method of distributing alternating-current electrical power). It provides heavy loads of electricity, such as those used by industry, businesses, or very high energy-consuming homes. With the advent of electric vehicles, more and more residential properties are opting to install these to future proof them with the growing need for smart home technology. Three phase installations require a larger meter box than the traditional single-phase smaller box.
What is the difference between single-phase and three-phase electricity?
Single-phase and three-phase electricity are both power sources, but they deliver different amounts of power. Domestic homes with central gas heating typically have a single-phase supply as it is smaller and often comes with this as standard. When you need two or more electricity meters, you need a three-phase supply.
The phase in electricity describes how the load is distributed. A single-phase alternating current (ac) circuit has two wires connected. In a typical circuit, there is one phase wire (the power wire) and one neutral wire, with current flowing between the phase wire (through the load) and neutral wire. The three-phase power circuit consists of three wires, each with 120 electrical degrees between it.
A single-phase power supply is usually used for residential homes, while a three-phase supply is usually used for commercial and industrial buildings. The main difference between single-phase and three-phase power supplies is that a three-phase power supply can accommodate higher loads. Typically, single-phase power supplies are used when the typical load is lighting or heating rather than large electric motors.
Three-phase vs. single-phase power
There is also an important difference between 3-phase power and single-phase power in the consistency of power delivery. In general, single-phase power supplies do not offer the same consistency as three-phase power supplies due to the peaks and dips in voltage. Three-phase power supplies deliver power at a constant rate.
A three-phase power supply is more efficient when compared to a single-phase system. Compared with a single-phase power supply, a three-phase power supply can transmit three times as much power while requiring only one additional wire (that is, three wires instead of two). Consequently, three-phase power supplies, whether they have three or four wires, use less conductor material to transmit the same amount of power.
Comparison of three-phase and single-phase power supplies
Some three-phase power supplies have a fourth wire, which is the neutral wire. Wye and delta are two of the most common configurations of three-phase systems. Delta configurations typically have three wires, while wye configurations may have a fourth wire, the neutral. In single-phase power supplies, the neutral is also present.
Whatever the distribution system type, whether it's single phase or three phase, it can serve many purposes. They are, however, quite different from each other.
Before deciding whether you need a three-phase electricity supply, you should consult a qualified electrician who can assess all the equipment you'll be running and determine how much power you'll need. If you require a three-phase power supply, Meterboxesdirect have both surface and recessed mounted three phase meterboxes available, as well as repair products for both.
To tell whether a property has a three-phase supply, look at the electrical fuse (sometimes called electricity supply, service head, or cut out). In most cases, a single-phase will have one fuse, and a three-phase will have three 100amp fuses.
What is a 3-Phase electric meter?
Most commonly, a 3-phase electric meter is used to measure the power of a three-phase electrical supply. Currently, consumers using three-phase electricity cannot get a digital smart meter installed. Still, business users can log their electrical consumption using AMR technology such as three-phase advanced meters.
The UK government ruled in 2018 that energy suppliers can offer consumers the choice between advanced meters and smart meters.
3-phase smart meter at home
Polyphase SMETS2 smart meters enable high volume and complex electricity users to join the smart, clean, green energy revolution.
In the UK, most households have a 'single phase' meter connected to 230 volts or 240 volts via two wires. However, many homes and businesses across the country operate on a three-phase connection with three active cables, or 'phases', and one neutral wire. These sites have a different kind of connection because they use higher loads of electricity and have more complex home energy set-up — such as solar panels, battery storage or an electric vehicle charger. These homes and businesses have been unable to use the latest smart metering technology until now.
Since the clean energy system of the future will rely on smart homes like these to generate power and share that power as part of a smarter grid, this was a problem the energy industry needed to solve with the introduction of the 3-phase SMETS2 smart meter.
The second-generation smart meter will allow customers to connect to the nationwide network run by Data Communications Company (Smart DCC), allowing seamless switching between energy suppliers.
You may need a meter upgrade if you install a smart home energy system, such as solar generation or an EV charger.
Which is the best option for my business?
Despite the benefits of smart meters being similar to those of AMR devices, the Government ruled in 2018 - in the interests of maintaining a competitive marketplace - that non-domestic customers (except for microbusinesses) will continue to be able to choose between the two technologies. Business consumers who use 3-phase electricity will now have the option of using the 3-Phase SMETs2 smart meter, which can only benefit the smart energy revolution.
Retrofitting 3-Phase smart meters
If you use three-phase electricity at your home or business, you can now benefit from having a three-phase smart meter (SMETs2) installed at your premises. Some of the UK's leading smart meter installers are currently working with energy supply partners to roll out the smart meter devices across the UK.
What is the difference between AMR and smart meter technology?
Despite their similar benefits, AMR devices and smart meters operate differently and rely on different technologies.
Even though the benefits of smart meters are like those offered by AMR, the Government has ruled in 2018 that non-domestic customers (except for microbusinesses) will continue to be able to choose between the two technologies.
Business consumers who use 3-phase electric supply will now have the option to get a SMETs2 smart meter, which can only be suitable for the smart energy revolution.
How does a smart meter benefit my business?
By installing a smart meter, if your business is not already using an AMR device, you will be able to join the smart energy revolution, which offers the possibility of reducing energy consumption and costs and carbon emissions.
Using an energy management platform, you can monitor, track, and take action to lower your usage with a smart meter.
By digitising the country's energy consumption, SMETs2 smart meters are also helping introduce innovative new products, tariffs, and smart technologies. Smart meters, for example facilitating electric vehicle charging, encourage more flexible energy use, thereby supporting decarbonisation and a more efficient grid.
In addition to helping your business, smart meters will also play a vital role in achieving the UK government's net-zero carbon emissions target by 2050.
