Smart meter rollout presents numerous technical challenges
The task facing the UK's energy suppliers is daunting given the technical complexity involved and the consequences of getting it wrong
Interest in smart metering from governments and utility companies has created something of a jamboree for hardware and software providers, with large multi-million pound tenders for appropriate equipment already on the table. DECC has published two tenders in the Official Journal of the European Union (OJEU) to support the rollout and analysis of information from smart meters to be installed in up to 30,000 homes across the UK, with each contract expected to be worth between £60m and £240m depending on its length, which will be anything between nine and 15 years.
These contracts include not only the smart meters themselves, but also back-end datacentre hardware and software and the communications and management services required to pull stored information from each device, present usage data to the customer, transmit it back to the utility company’s datacentres and integrate it with existing customer relationship management (CRM) and billing systems.
Much of the discussion around what the UK smart meter specification should look like has centred on the communications piece of the jigsaw, for which various different technologies are suitable. Wi-Fi is one candidate for the home area network (HAN), which interconnects the smart meters to in-home displays, broadband routers, communications link and other sensors at the customer location, for example. But Wi-Fi signals do not work well inside some buildings, particularly those with thick walls and ceilings, while the 2.4GHz and 5GHz wavebands it uses are subject to interference from a range of other equipment using the same frequencies within the near vicinity. Also, Wi-Fi electricity consumption is high, meaning additional cost for the customer.
Lower power alternatives include ZigBee, a kind of slower, lower cost Bluetooth with a throughput of 250Kbit/s, which is more than enough to carry data from smart meters, and which can operate in either the 2.4GHz or 868MHz frequency band. Some suppliers are also looking into private mobile radio (PMR) to form the HAN environment, including the wireless version of the Meter-Bus (M-Bus) standard already used in parts of Europe. The Wireless M-Bus operates in the 868MHz band and would isolate the smart meter network from internal Wi-Fi networks to avoid interference problems.
Smart meter rollout presents numerous technical challenges
The task facing the UK's energy suppliers is daunting given the technical complexity involved and the consequences of getting it wrong
Another option for the HAN is power line communications (PLC), already successfully deployed by Italian utility company Enel, which rolled out smart meters to an estimated 27 million customers between 2000 and 2005. PLC, which transmits data at up to 28Kbit/s over standard electricity cables, both within the building itself and to the electricity substation, has the advantage of being low cost, secure and relatively reliable, but it needs communications equipment to be installed at each local substation or in an external cabinet close to the customer location. The Enel deployment involved smart meters supplied by Echelon transmitting data over low voltage power cables to data concentrators, which then sent information via IP networks to Enel’s servers.
Nor can electricity suppliers assume that every home or office they want to put a smart meter into has any form of broadband, internet or telephone connection that allows the data collected from smart meters via the HAN to be transmitted back to the supplier’s headquarters for billing and management purposes.
Again, a variety of options are being considered for the wide area network (WAN) part of the data path, with individual premises likely to require different approaches depending on their location. GSM/GPRS networks are fine where there is sufficient mobile coverage, for example, but in remote rural areas alternatives might include satellite communications links, wireless mesh or WiMax networks that collect data wirelessly and feed it into a central wired hub before sending it via a wired or cable network connection.
Various companies manufacture the smart meters themselves, including Landis+Gyr (L+G), acquired by Japanese electronics giant Toshiba for $2.3bn in May 2011. L+G offers a portfolio of different equipment including integrated automated meter management (AMM) and advanced metering infrastructure (AMI) platforms, communications systems and software, meters, meter data management and services. Its Libra 350i Series advanced gas meter provides various communications options, including low power radio or wired M-Bus communication, and data from the gas module to the electricity meter (for duel fuel customers) can also be sent back via utility software through a GPRS port.
Other smart meter manufacturers offering devices accommodating a whole range of wired and wireless HAN and WAN options include Elster Group, Ambient, Sensus and Trilliant, with in-home displays made by anyone and everyone including Tendril and OpenPeak, according to clean technology market research firm PikeResearch.
The last aspect utility suppliers have to consider is how to convert the data collected from smart meters into formats that can be easily integrated into their existing customer relationship and billing systems, either through specialist middleware designed specifically for the task, software customisation or add-on application programming interfaces (APIs) that perform the necessary conversion.