As the demand for renewable energy grows, more companies are searching for stronger and more efficient ways to provide green energy. Battery Energy Storage Systems (BESSs) are one way that energy companies are working towards increasing renewable energy supplies and having them readily available when needed by consumers.
Connected Energy, a builder and operator of second life BESSs, had been searching for a communications partner and system to incorporate within its E-STOR BESS, with a purpose to better enable thousands of Electric Vehicle (EV) batteries to be aggregated, controlled, and reused and thus, create second life batteries.
Second life BESSs extend the life of EV batteries in industrial and commercial-scale, stationary energy storage systems. Not only is using recycled or second life batteries reducing the disposal issues of the financial burden, but also reducing the environmental cost of doing so.
By 2030, a million tonnes of EV batteries are expected to be available for reuse. Global requirements for stationary energy storage could be completely met by second life batteries by 2035. The communications answer HMS Networks’ Ixxat brand is set to play a major part in some major, innovative, green energy projects, having been selected as a communications solution partner by Connected Energy.
Connected Energy is using HMS Network’s Ixxat CANbridge NT 420 to bridge its technologies together and allow for stronger communication between the batteries and its management systems. Head of Supply Chain at Connected Energy, Jonny Cogman, said it is pivotal that as many Controller Area Network (CAN) channels as possible are available for communication.
Mr Cogman said HMS’s CANbridge was not only suitable to incorporate within its E-STOR systems, but was ideal for its second life battery goals.
“We retain the OEM battery management systems (BMSs) for each of the individual second life batteries that we fit into our E-STOR systems,” Mr Cogman said.
“This means we can communicate with each battery, as and when required, and collectively the BMSs create the foundation layer of the system’s overall control system.
“Reusing the existing BMS, giving them a second life also, maximizes the ‘green’ credentials of the E-STOR brand.”
The BMSs use CAN bus for sending and receiving control signals, reflecting their origins in the automotive sector. Connected Energy’s technology has been proven, commercialized, scaled-up, and installed in the UK, Belgium, Germany, and the Netherlands. The biggest system currently in operation is 1.2MW, but this will be surpassed in 2022 when several multiMW schemes are expected to come online.
Finding the right solution
“There are many CAN solutions available on the market and we reviewed several before choosing to standardize on the Ixxat CANbridge solution from HMS Networks,” Mr Cogman said.
“The deciding factor was that it proved very easy to program, but other benefits include that it is easy to install, while its robust build means that its long-term reliability is ensured. The longevity is particularly important because the life expectancy of an E-STOR installation is measured in years and decades.”
CAN uses a serial, message-based protocol to minimise the amount of heavy and expensive copper wire used in vehicles. This means signals to and from each BMS are all sent along the same wires, or ‘bus’, with each signal having a header to identify it and keep it distinct from other signals.
Importantly, high-priority signals take precedence over less critical ones on the bus, so that there is always an immediate response for functions such as braking and turn signalling.
The E-STOR control system architecture uses an Ixxat CANbridge NT 420 for interfacing with the batteries, then steps up through layers of intermediate control using Modbus to the central (EMS) or overall controller.
This manages the installation’s functional operations so that it can be switched in and out in response to demand, supplying power when needed and recharging when there is surplus power in the grid.
Furthermore, the transmission of data such as temperature, voltage and current is done in this way.
“Our early installations were quite modest, typically 60kW, but everything was designed so that over time we have been able to scale up to megawatt systems and are now working on utility-scale projects,” Mr Cogman said.
“The flexibility and adaptability of the Ixxat CANbridge NT 420 has let us design a control system architecture that is suitable for our range of installations.”
CAN vehicle applications
CAN was originally developed for onboard vehicle applications and allows the many microprocessors fitted to modern cars and other vehicles to communicate with each other’s applications without a host computer.
It has also become a popular choice for other non-automotive applications, including general automation, motorized prosthetic limbs, electronic gear changes on sports bicycles and emerging fields such as EV charging stations.
HMS Network’s CANbridge solution’s easy-to-install functionality and robust build mean that it provides long-term reliability for E-STOR systems, making it a critical element for EV second life batteries and furthering the development of renewable energy sources.
This sponsored editorial is brought to you by HMS Networks. For more information on Ixxat’s solutions, go to: https://www.ixxat.com.
