The Smart Meter Home Area Network
The Home Area Network or HAN is similar to your home broadband wireless network and will be used to communicate between the meters, the In Home Display (IHD) and other items as and when they become available.
The IHD is a small standalone display which you might typically keep in your kitchen which shows your current energy consumption for both electricity and gas. It shows that as kWh (kilowatt hours, the unit used to measure energy usage) and in pounds and pence. It also shows your energy usage over various time periods, the current day, week, month and year. IHDs have a minimum set of features which are specified in the Smart Metering Equipment Technical Specifications.
Normally the Communications Hub that manages the HAN sits on top of your electricity meter and communicates with the electricity meter, gas meter and IHD.
The communication protocol used for the Smart Meter HAN is Zigbee as it is simple, inexpensive, low power and secure. The range of this technology is about 15m, but this is reduced by obstructions such as walls and doors.
Where the meter is a long way from the location of the IHD, 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 or Dual Band HAN) available from mid 2020 will improve this for about 3.5% of properties but that still leaves a large number for whom Smart Meters won't work.
For these final properties, for example where meters are in a basement a long way from the customer's IHD, a separate company has been set up to investigate solutions, prepare contracts and procure the equipment. The company is the Alt HAN Co Ltd and solutions are expected in 2021.
- Standard HAN 2.4GHz
- 70% of premises
- Normal small and medium houses
- Nominal range of 15m
- 25% of premises
- Large houses and buildings, thick walls
- Signal can travel further but is lower bandwidth and therefore slower
- Available August 2020 for testing, January 2021 for mass roll-out
- More expensive than Standard, additional £24.20 per meter set
- Between 2% and 3.5% of premises
- Long distance between meters and IHD, for flats with meters in a basement
- Most expensive solution
- New company Alt HAN Co Ltd formed to manage this
- Solutions being tested:
- Installed from 2021 onwards
- Total additional cost £290M
- Between 1.5% and 3% of premises.
- Extreme distances
- Faraday cage buildings
Interference with Wi‑Fi
The operation of the HAN should not interfere with your Wi‑Fi despite operating in the same 2.4GHz band. Many appliances operate in this unlicensed band and are designed to choose a channel with less traffic and then share that channel with the other users. There could be some interference at the beginning as devices choose the best channel but this is unlikely.
For comparison with the Smart Meter frequencies shown above, here are the main Wi‑Fi frequencies.
|Frequency Band (MHz)||Description|
|2400||The 2.4 GHz band is the most widely used of the bands available for Wi‑Fi, being used for 802.11b, g, & n. It can carry a maximum of three non-overlapping channels. This band is widely used by many other non-licensed items including the Smart Meter HAN, microwave ovens, Bluetooth, etc.|
|5800||The 5.8 GHz band provides additional bandwidth and is used by 802.11a & n. It can carry up to 23 non-overlapping channels, but gives a shorter range than 2.4 GHz. 5GHz Wi‑Fi is preferred by many because of the number of channels and the bandwidth available. There is also less traffic on this band currently, resulting in less interference.|
(Page updated: 2022-03-25)
Questions & Answers
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)
The IHD still needs a link to the meters to retrieve the data first so CADs do not provide an alternative solution where the meters and IHD are separated by a large distance. (Updated: 2020-03-05)
In Smart Meters the Zigbee protocol is used to communicate between the communications hub, electricity meter, gas meter and IHD (In Home Display). (Updated: 2020-02-09)
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 (In Home Display) to apply your credit. This very difficult to do on the meter so use the IHD if you can. (Updated: 2019-10-21)
For some buildings like blocks of flats or where walls are very thick, the smart meter can't communicate with the Comms Hub. So by mid 2020, a more sophisticated hub with a choice of frequencies will be available. 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 95% of premises. (Updated: 2020-02-09)
A different communications method (Zigbee 868MHz) available from mid 2020 will improve this for about 3.5% of properties but that still leaves a large number for whom Smart Meters won't work.
For these final properties, for example where meters are in a basement a long way from the customer's IHD, a separate company has been set up to investigate solutions, prepare contracts and procure the equipment. The company is the Alt HAN Co Ltd and solutions are expected in 2021. (Updated: 2021-10-03)
- Hildebrand Technology Ltd can retrieve data from your smart meter daily to display it in their Bright app. You can also swipe the screen in the app for a refresh via DCC and your smart meter.
- For updates every 10 seconds you could purchase the Hildebrand IHD/CAD. This device connects to the communications hub on your smart meter via the HAN as normal but passes the data collected via your home broadband to Hildebrand Technology Ltd so that it can be shown on the Bright app with less delay.
Our recommendation would be to let your supplier sort it out, as a communications hub (868MHz) with better reach will be available to suppliers to install with SMETS2 meters where needed from mid 2020. (Updated: 2020-02-09)