Performance assessment of UK's cellular network for vehicle to grid energy trading: Opportunities for 5G and beyond

The proliferation of plug-in electric vehicles (PEV) and advances in high-speed low latency communication networks redefine the relationships between electricity providers and end-users. A group of PEV owners, coordinated by an aggregator, can participate in ancillary energy markets to stabilize electricity grids and, in return, receive payments for services rendered. However, PEVs are typically parked across a dispersed region possibly with diverse signal strength and data rates. Vehicle-to-Grid (V2G) applications have tight latency (e.g., 500 ms to 2 seconds) and packet-loss requirements, hence, the supporting communication infrastructure should be carefully evaluated for real-world implementations. In this paper, we assess the performance of the internet-based 4G cellular network in the United Kingdom to evaluate these key metrics. We develop a low cost and easily deployable testbed platform to collect and analyze the latency and packet loss rate of different package sizes, transport protocols, and signal strengths. Due to the availability of hardware resources and city-wide coverage of 4G networks, a single parking lot to aggregator scenario is emulated. The results show that in most cases current 4G network can deliver packets less than 500ms which is required in fast frequency response applications in the UK. On the other hand, for more complex scenarios such as multi-aggregator to distributed clients, there is a need to use 5G and beyond to meet the latency requirements. To the best of authors' knowledge, this is the first study focusing on the field testing and assessment of an actual internet-based communication network for V2G applications.