05.03.2024

More speed in the smart meter rollout – what are the challenges?

The integration of small-scale flexibility plays a central role in the electricity grid, which is increasingly fed from renewable, volatile sources. Intelligent metering systems, also known as smart meters, are the basic digital technology that makes this possible. Their functionalities, such as the transmission of measured values and control signals via smart meter gateways (SMGW), not only allow small-scale flexibilities to be integrated into the energy system and thus relieve the electricity grids, but also open up opportunities for producers, consumers and prosumers to actively participate in the energy market. The number of smart meters installed in Germany is therefore set to increase to around 16 to 18 million over the next few years [1]. We looked at which process steps have an impact on the smart meter rollout and interviewed project partners from the unIT-e² project involved in the rollout about the current challenges and possible solutions. Figure 1 shows the process steps and developments. The content has been published in full in the journal VDI Energie und Umwelt 1/2 2024 and is available in the download area.

Figure 1 Process steps in the smart meter rollout and current developments

The GNDEW simplifies the implementation of new tariff use cases

New use cases require the implementation of additional functionalities in the SMGW. In addition to standardized tariff use cases (TAFs), software solutions must be developed for the operation and administration of the devices. Finally, the device must be recertified by the German Federal Office for Information Security (BSI). The regulation that previously required devices from three independent manufacturers to be certified no longer applies. This simplifies the rollout, although the frequently changing regulations always entail a lot of development and certification work. “With so many players, you can’t do anything on your own – coordinating changes is a bottleneck,” says one interviewee. For example, dynamic electricity tariffs must be offered to all consumers from 2025. Such tariffs can be realized with TAF 5 by implementing event-variable tariffs [2]. “Overall, the implementation time is around six to eight months,” said one interviewee.

“The calibration law will massively change the rollout”

The devices still have to be calibrated. Until the beginning of the year, calibration law required SMGWs and individual components to be certified by the regional calibration authorities. This caused considerable effort. To counteract this, a law amending the calibration law was passed on January 31, 2024 [3]. This will simplify the calibration law regulations on software updates and remove the time limit on calibration for smart meters. The simplification of calibration law “will massively change the rollout”, according to one interviewee.

“As soon as problems arise, metering point operation becomes uneconomical”

The cost-effectiveness of metering point operation is a challenge for metering point operators. The GNDEW stipulates upper price limits: for example, the costs to be paid by consumers with an annual electricity consumption of 6,000-10,000 kWh are capped at €20 per year. In this case, the grid operator can be charged up to €80 per year. The total amount of €100 per year remains unchanged from the 2016 GDEW.

From the manufacturing of devices to transportation and installation, the entire supply chain is subject to strict safety regulations. Installation must be carried out by specially trained electricians. The shortage of specialists in Germany will therefore play a role in the installation of around 16-18 million devices. The simplification of the secure supply chain envisaged by the GNDEW is intended to ensure that the rollout processes are more suitable for mass business and could thus counteract a possible slowdown due to staff shortages.

Today, measurement and control signals are mainly transmitted via the mobile phone network. Even during installation of the devices, inadequate mobile phone reception can lead to errors that require additional manual work by specialist personnel or even termination of the installation. “As soon as problems occur, metering point operation becomes uneconomical,” says one interviewee. To counter this problem, some metering point operators also use broadband powerline communication to transmit data over short distances. Other alternatives such as using their own fiber optic network or in-house internet connection are possible, but are not used in practice due to disproportionately high costs or a lack of reliability. The 450 MHz radio network, which is being set up throughout Germany for energy and water supply applications, is very promising. It should achieve better penetration down to the cellar so that problems during commissioning can be avoided in future. However, the cost-effectiveness of metering point operation remains a challenge. “The costs have risen, but the upper price limits remain unchanged from the point of view of the metering point operator,” said one interviewee.

Conclusion

Smart meters are a fundamental infrastructure in an increasingly climate-friendly, decentralized energy system. With the GNDEW law, the German government wants to create a framework under which the smart meter rollout can gain momentum. In our discussions with stakeholders who are implementing the smart meter rollout, we were able to identify a number of challenges that could continue to slow down the rollout. The most important points mentioned were a shortage of skilled workers and technical challenges when installing new devices, the cost-effectiveness of metering point operation and high development costs due to frequently changing requirements and regulations. The GNDEW is intended to address challenges in the installation of devices through improved logistics suitable for mass business and 1:n metering. The elimination of the three-manufacturer rule is also an important step towards reducing the development time for new functionalities. In order to ensure the economic efficiency of metering point operation, our discussion partners still see a need for discussion.

The content presented was developed in the unIT-e² project. The research project is funded by the Federal Ministry for Economic Affairs and Climate Protection (BMWK) (funding code: 01MV21UN11 (FfE e.V.)). The German Aerospace Center (DLR) is responsible for the three-year joint project.