Ericsson, together with Telefónica Germany and E.ON Research Center at RWTH Aachen University, have demonstrates the feasibility of using LTE networks in smart meters for the energy sector. Trials proved LTE prioritisation, a standard feature of LTE, can provide a highly reliable and flexible alternative to existing powerline or fixed network connections of smart meters.
Smart meter roll-out planning is picking up speed in Germany, among other places. At the same time, on-going LTE network deployments open new opportunities for utilities to use public networks for communicating with their smart meters. LTE can provide a highly reliable and flexible communications link from the smart meter to utility IT systems, as the trials showed.
Utility IT systems can use the information collected from smart meters as a tool to help them manage their power networks in the context of increasing integration of volatile renewable energy sources, such as wind and solar power, into the power network.
Communication of new energy tariffs can be sent to the meter by the utility to encourage the use of energy at the time when it is available in the network from renewable energy, for example, on a sunny or windy day.
Sven Koltermann, Head of Energy Sales in Telefónica Germany, said: “We see the trial results as confirmation that public LTE networks, such as Telefónica Germany’s, offer a reliable and cost effective communications option to utilities companies deploying smart meters. Such mechanisms for the utilities and their grid stability should always be introduced in close cooperation with German regulatory bodies.”
The trials demonstrated that even under heavily loaded radio network conditions, the stream of messages from the smart meters can be received within the expected transmission time period of less than 100 milliseconds at the central utility IT systems over a commercial Ericsson LTE base station.
Professor Monti, Director of the Institute for Automation of Complex Power Systems (ACS), E.ON Research Center at RWTH Aachen University, said: “As the installation of smart meters progresses, and communications and power network technology develops towards smart grids, more and more business opportunities are opening up for utilities.
“They can improve the services they offer their customers and to optimise their networks, enabling the large-scale integration of renewable energy sources into the power generation mix while maintaining the highly reliable power network service that society needs to function efficiently.”
LTE offers features that will make it the solution of choice for many use cases for utilities. The new features available in LTE Release 13 and beyond will enable further improvements in LTE performance for utility use cases and when 5G is available, even the most challenging of utility real-time use cases will be addressed by wireless networks, Ericsson said.
Dr. Fiona Willliams, Research Director Ericsson, added: “The trials we have run with Telefónica and RWTH ACS show that LTE is an excellent communications option for utilities rolling out smart meters. We were happy to see that the QoS features of LTE fully met the communication requirements for power network automation, which are far more stringent than other requirements specifications for smart meter measurement acquisition.”
The advantage of applying the QoS features to the meter traffic is that even in the rare case of overload conditions, the smart meter messages will not be delayed or dropped and will be delivered to serve smart meter applications. This means that messages sent to a pre-paid meter to reconnect a customer that has just phoned to buy a top-up for their electricity or gas meter, will happen instantly, regardless of the network load conditions.
In the trials, the stream of message from the smart meters was prioritised using the Quality of Service (QoS) features of LTE. Using prioritisation, smart meter messages were promptly received even in an overload situation, when other traffic on the network had heavy delays.
The trials were conducted using an Ericsson LTE base station set up at the ACS Institute of the E.ON Research Center at RWTH and connected to the Ericsson Core Network facilities available at Ericsson Eurolab in Aachen. The RTDS power network simulator of the E.ON Research Center was used to generate the stream of messages according to the specifications of the smart meter use case provided by Telefónica.
The tests followed an independently conducted set of simulations of the messaging use case on the Ericsson LTE high performance simulator. The results from the simulation showed that the prioritised MMS message streams were transmitted promptly even in radio network overload conditions. These simulation results were confirmed by the tests sending the messages over the air with the real base station.