Types of Smart Meter
There are two main types of smart meters – the older models known as SMETS 1 (Smart Meter Equipment Technical Specifications) and the newer versions that were rolled out in 2018, known as SMETS 2.
- SMETS 1 – Most of these communicate with your supplier through the 3G mobile network. Unfortunately a number of different systems, not linked together, are used to manage these meters and so if you change suppliers it is likely that your new supplier will not be able to operate your Smart Meter and it will become a ‘dumb’ meter for operational purposes.
- SMETS 2 – This specification is more advanced and meters were first rolled out in 2018. A purpose built communication network is used with these meters and all suppliers will use it this – making switching easier and keeping your smart meter smart.
The good people at Elexon (they manage electricity industry data) are now reporting SMETS1 and SMETS2 meter installation data every month. Although this is for electricity only it gives a good indication of overall progress.December 2019 Electricity Install Progress Report
In December 2019 the SMETS2 installs were 159k, down from 201k in November. The SMETS1 installs dropped slightly to 23k from 29k in November. So the odds of you getting a SMETS2 meter have worsened to 61% from 77% in November. However this is to be expected in December when installs always fall to their lowest level. We would like to see that get to 85% before we recommend people say Yes to a Smart Meter.
We would suggest that you continue to say no to a smart meter, as there is still a good chance you would end up with the older model which is less secure and has less features.
Here is a link to Elexon’s report: https://www.elexon.co.uk/about/key-data-reports/smart-meter-technical-detail-report/.
Wide Area Network
The Wide Area Network or WAN is the name given to the communications network between the meters and the company responsible for collecting the data and passing it on to other businesses such as suppliers. This company will usually be the DCC (Data Communications Company) which the government has set up especially for this role supporting the final SMETS2 meters. Depending on the Communications Service Provider, which varies by areas of the UK, the technology can change depending on what works best in a local area. Sometimes your meter will communicate directly with DCC and sometimes it will talk through the meters around you to reach a particular meter which has direct communications with DCC. This form of communications looks like a mesh when you draw out the possible links between meters and is therefore known as a Mesh network.
Home Area Network
The Home Area network or HAN is a bit like your home broadband wireless network and will be used to communicate between the meters, the In Home Display (previously known as Smart Meter Display or Home Energy Monitor) and other items as and when they become available. However where the meter is a long way from the location of the In Home Display, or thick walls are in the way, the current technology (Zigbee at 2.4GHz) won't work. This could be the case for up to 30% of properties.
A different communications method (Zigbee 868MHz) will improve this for about 3.5% of properties but that still leave a large number for whom Smart Meters won't work. Zigbee 868MHz should be available some time in 2019.
Smart Meters can send information about the meter's environment and status as well as meter readings. This information can be used to diagnose meter faults, detect theft and security issues. There are some 250 events which can be sent in this way, suppliers and distributors will monitor these alerts, and take action at the appropriate point. For example a memory alert may mean the meter is faulty, whereas a reverse flow alert could mean that someone has reversed the meter in order steal energy.
Security has been considered very carefully for Smart Meters. The communications network is not part of the internet, it is a closed network only accessible to parties with the right security keys and physical connections. Additionally there is no central database containing customers' information, the information is only stored on the Smart Meters and sent through DCC onto Suppliers and other parties who have a right to that data and where the customer has given them permission. The customer information inside messages is encrypted and only the receiving party can look at the data, the DCC cannot view the data. The parties receiving the data undergo a rigorous security assessment at the beginning and then have regular security audits.
The National Cyber Security Centre has an excellent document explaining how the security works in relatively simple English.
The ability to purchase electricity and gas on a PAYG (Pay As You Go) basis is a big advantage of Smart Meters. Once you've paid, top up can be sent to your meter automatically without having to use chargeable key fobs. If communication to the meter is down you can still top up by entering the long reference number provided with your purchase into the meter, although this may not be an easy thing to do. For customers on PAYG who have difficulty with reliable communications and entering the long number, a separate number entry pad can be provided by your supplier. However it should be noted that many suppliers didn't start to offer the PAYG service until late 2018.
As well as Suppliers getting information from smart meters the Distribution Network Operators (DNOs), who look after the cables in the ground, will also get information. They can use this information to detect voltage drops and power cuts and to help analyse the performance of the network.
Both SMETS1 and SMETS2 meters are being installed currently. If you are wondering if you have a SMETS2 meter, look up your meter model number in the table below which lists all currently approved SMETS2 meters.
|Manufacturer||Model||ESME / GSME||Type|
|Aclara||SGM1412||ESME||4 terminal with ALCS + Boost|
|Aclara||SGM1412B||ESME||4 terminal with ALCS + Boost|
|EDMI||ES-10A||ESME||4 terminal with ALCS + Boost|
|GWI||G4-MG-SE-GM-V2 FVI||GSME||Diaphragm: Front Viewing Index|
|GWI||G4-MG-SE-GM-V2 TVI||GSME||Diaphragm: Top Viewing Index (for semi-concealed applications)|
|Honeywell||AS302P (BBBBBSYAHA-P)||ESME||4 terminal with ALCS + Boost|
|Itron||EM425-UK2||ESME||4 terminal with ALCS + Boost|
|Kaifa||MA120||ESME||4 terminal with ALCS + Boost|
|Landis & Gyr||E470-5394||ESME||4 terminal with ALCS + Boost|
|Landis & Gyr||E470-5424||ESME||4 terminal with ALCS + Boost|
|Landis & Gyr||G470-672||GSME||Ultrasonic|
ESME = Electricity Smart Metering Equipment
GSME = Gas Smart Metering Equipment
ALCS = Auxiliary Load Control Switch.
Diaphragm type gas meters have been used for many years. Within the meter there are two or more chambers formed by movable diaphragms. With the gas flow directed by internal valves, the chambers alternately fill and expel gas, producing a nearly continuous flow through the meter. As the diaphragms expand and contract, levers connected to cranks can link to a counter or provide an electrical pulse to measure the gas volume.
Ultrasonic gas meters measure very small difference in time that it takes an ultrasonic pulse to travel with and against the flowing gas stream. A microprocessor can then calculate the gas used. The main advantages of ultrasonic gas meters are that they have no moving parts and are therefore more reliable, and they are more accurate than conventional gas meters.
Existing SMETS1 meters in the table below will be migrated to the new DCC SMETS2 system through the enrolment and adoption process. If you are wondering if you have one of these SMETS1 meters, look up your meter model number in the table below.
|Manufacturer||Model||ESME / GSME|
|Itron||RF1 sV ZB||GSME|
|Landis & Gyr||E470||ESME|
|Landis & Gyr||G370||GSME|
|Landis & Gyr||G470||GSME|
|Secure Meters (UK) Limited||EG4v10||GSME|
|Secure Meters (UK) Limited||Liberty 100||ESME|
|Secure Meters (UK) Limited||Liberty 110 (Single Element)||ESME|
|Secure Meters (UK) Limited||Liberty 110 (Twin Element)||ESME|
When will SMETS1 meters be connected to DCC?
The original milestones have been delayed and are subject to a DCC consultation which closed on 20 November 2019. The proposed dates are shown below.
SMETS1 meters will be migrated to DCC in five batches over three capability phases. Once the capability is made ready on the dates below, the migration will happen within the following months.
- Initial Operating Capability (IOC) – meters operated by CGI Instant Energy (IE)
- 24 Nov 2019 - Elster Honeywell and Itron meters
- 23 Feb 2020 - Aclara meters
- Middle Operating Capability (MOC)
- 15 Mar 2020 - Elster Honeywell meters currently operated by MDS (Morrison Data Services)
- 28 Jun 2020 - Secure meters operated by the Secure Meters group
- Final Operating Capability (FOC)
- 26 Jul 2020 - Landis + Gyr (L+G) meters currently operated by either BG SMSO (Smart Meter System Operator), DXC or CGI Instant Energy (IE) and, if directed by Government, the EDMI meter group.
Questions & Answers
Does my SMETS1 meters have to be replaced?
See our Technical page for a list of SMETS1 meter types that can be upgraded. (Updated: 2019-10-21)
What is the SMETS1 end date?
Additionally due to the extra complexity of prepayments meters, the end date for them is 15th March 2019.
But what does this mean for you - not a lot as it mainly impacts the suppliers, but at least it means the better SMETS2 meter are coming in volume. (Updated: 2018-10-27)
Are smart meters safe?
Can a Smart Meter interfere with my WiFi?
Both your WiFi and the Zigbee network used by Smart Meters operate in the same 2.4GHz radio band and the band is divided into channels. Most modern WiFi routers can scan channels in order to pick the ones with the least interferences from other devices and the Smart Meter Zigbee system can do the same. As some door bells and remote controls can also use the 2.4Ghz band it may take an hour or two for the best channels to be chosen.
If interference problems continue, you can log onto your WiFi router and select the channel manually to see if that helps. It is not possible to override the automatic channel selection on the Smart Meter. (Updated: 2020-01-20)
What is a SMETS2 meter?
When will my SMETS1 meter operate again?
Provided your meters are on the list of meters which can fit into this process on table SMETS 1 Meters for adoption by DCC they should start working again during that transfer period. (Updated: 2019-10-17)
How are they tested for accuracy through their life?
Will my meters have to be changed if I change supplier?
SMETS1 meters usually require replacing when you change supplier to retain a smart service. However due to the large volume of SMETS1 meters, there is now an agreement to allow SMETS1 meters to be upgraded and enrolled into the new DCC systems and thus allow smooth switching for customers. See our Technical page for a list of SMETS1 meter types that can be upgraded. (Updated: 2019-10-21)
What is Zigbee?
In Smart Meters the Zigbee protocol is used to communicate between the communications hub, electricity meter, gas meter and IHD. (Updated: 2020-01-20)
Do I have to be at home for the installation?
I have a SMETS2 meter. Will it work after switching suppliers?
How does a smart meter work?
Should I wait for a SMETS2 meter?
Can my supply be turned off remotely?
How do I top-up my smart meter PAYG if the mobile network is down?
Firstly you can use the emergency credit that most suppliers offer. If that runs out you can enter the long authorisation number that you received when you paid for the credit into the meter or IHD to apply your credit. This very difficult to do on the meter so use the IHD if you can. (Updated: 2019-10-21)
How do Smart Meters send data?
What is a Dual Band Comms Hub?
For some buildings like blocks of flats or where walls are very thick, the smart meter can't communicate with the Comms Hub. So in 2020, a more sophisticated hub with a choice of frequencies will be installed. These are called Dual Band Comms Hubs. They use a HAN frequency of 868MHz along with the existing 2.4GHz frequency. Dual Band Comms Hubs (DBCH) are expected to increase coverage to 96.5% of premises. (Updated: 2020-01-07)
Can I look at my energy usage on the internet?
How long will it take to install a Smart Meter?
Your electricity and gas will only be off for about 20 minutes though. (Updated: 2019-10-21)
How much data is stored on a Smart Meter?
Why does my IHD show CO2?
Can I lay a cable to help join the devices together?
Our recommendation would be to let your supplier sort it out, as more powerful communications hub (868MHz) will be available to suppliers to install with SMETS2 meters where needed later in 2019. (Updated: 2019-10-21)
Can smart meters be upgraded?
Why is two way communications important?
Are there special considerations for the location of a Smart Meter?
How do I know the meters are accurate?
How does the smart meter record energy generation if a solar panel is installed?
- Active energy import (Wh) - this is what we are billed for normally
- Reactive energy import (varh)
- Active energy export (Wh) - this is your useful export power
- Reactive energy export (varh).
What is a smart meter?
What is dithering?
How often will my IHD (In Home Display) be updated with data from my meters?
How do I read a smart meter?
My supplier says my signal is too weak?
For SMETS1 meters the installer will usually test on site and make a decision there and then whether to install. If there is not a sufficient signal they will usually walk away.
For SMETS2 there are more options. The communications are provided by the Data Communications Company (DCC) and suppliers can check that a premises has communications before visiting a site. Once on site they can check with a signal checking device if the signal is strong enough in the meter location. If it isn’t they can fit a number of different aerials to try to boost the signal. If that doesn’t work an external aerial or an alternative mesh communications method is available in some areas. Even then they can leave the meter de-commissioned and ask the DCC to get the communications working. (Updated: 2017-02-01)
What is a PPMID?
What is a traditional meter?
How do I read an In Home Display?
Are the meters battery powered?
Could my IHD (In Home Display) link to my neighbour's meters?
Do I require a broadband connection or wi-fi in my home to be able to use a smart meter?
What is a SMETS1 meter?
Do smart meters work with home generated renewable energy?
However as this is not a common requirement suppliers have been slow in implementing systems to support it - you will have to shop around for the supplier which can support your requirements. (Updated: 2019-10-21)