After I have listened for 15 minutes, I slow down guiltily. Reducing my speed by 20 or 30 km/h would still be fine. I would save fuel and release less CO2 into the atmosphere. Thanks for reminding me. In the daily hustle, I often suppress it. However, the truth is: Climate change is advancing at an unstoppable pace. For as long as I have followed political decision-making, scientists and governments have been struggling to find forward-looking concepts, and yet they cannot even agree on the most basic necessities. Yes, the entire process should be much faster.
However, there is also light at the end of the tunnel! While discussions are still taking place at round tables worldwide, a promising development is gaining momentum: electromobility. Its vision: The long-term reduction of CO2 emissions by using electric vehicles in the private and public transport sector. Meanwhile, considerable technical progress is being made, e.g. in the public transport sector: The number of e-buses continues to grow steadily. As a result, there is also a growing demand for a comprehensive, high-performance charging infrastructure.
Challenge The technology
Apart from logistics consideration, there is also a range of technical challenges that needs to be addressed: For the lithium-ion batteries, which are used in the vehicles and charging stations, to reach optimum availability and a long service life, they need to be cooled effectively.
This is because lithium-ion batteries are rather human-like in this context: They feel the most comfortable at an ambient temperature between 20°C and 30°C. This is the range in which they reach their maximum electrical power. If the temperature is too low or too high, it has a negative effect on the performance and service life of the batteries. Without precise temperature control, the batteries of electric vehicles cannot reach the intended range, and operation above 40°C can even lead to permanent damage.
This is the major challenge presented by all types of energy storage systems. During charging and, in particular, during fast charging, excessive heat is produced in the various components. This explains the need for efficient cooling systems that ensure the reliable temperature control of the energy storage systems.
To avoid performance issues or malfunctions of the batteries from the outset, technotrans offers extremely high-performance and reliable systems based on a liquid cooling concept which is favoured by most vehicle manufacturers. This cooling concept is ideal for ensuring a constant operating temperature in the optimum range as liquid cooling systems can transport heat in a very uniform manner and remove large amounts of heat quickly. „The cooling system must work so that the vehicles can be charged and are ready for use,“ says Bastian Thiel, sales manager at technotrans.
technotrans already caused a stir with its first development project centred on a battery cooling system for e-mobility applications: technotrans has developed a new water cooling system for a catenary-free tramway system in Qatar. This system is integrated in the roof of the trams together with the energy storage system. Despite the extremely high temperatures – often higher than 40°C – the innovative cooling system ensures that the batteries maintain their optimum operating temperature of a maximum of 20°C at all times. This innovation by technotrans made the project a huge success. However, it does not end there: Thanks to the battery-capacitor combination, the energy consumption of the new e-tram is 30% lower than that of comparable catenary vehicles.
In a first phase, the emission-free passenger train will replace diesel trains on routes for which electrification would be extremely difficult, if not impossible. The drive system uses a combination of lithium-ion battery systems and hydrogen fuel cells. When hydrogen and oxygen are converted into water, electricity is generated. This electricity is used to charge the batteries and to power the electric motor. The technotrans battery cooling system ensures a constant temperature level and, thereby, the efficient and uniform operation of the hydrogen-powered train.
„This large-volume order boosts our dynamic development and our standing in this high-growth market,“ says Finger. An important factor for the assignment of the order is the long-standing solution competence of technotrans. „Sophisticated projects like this require far more than only off-the-shelf standard products. Instead, our customers look for a high level of flexibility and adaptability, and this is exactly where technotrans is specialised.“
As a result, technotrans further expands its leading position in the rail sector, expands its area of expertise and strengthens its business with series devices qualified for use in trains.
It is a milestone for the high-growth market of sustainable mobility: technotrans supplies a customized battery cooling solution for the world's first hydrogen fuel cell passenger train. As technotrans is strongly committed to sustainable and consistent action, it uses the refrigerant R1234yf, which is non-ozone-depleting and nearly carbon-neutral with a GWP value (global warming potential) of 4.
„Once again, this project showcases our technological leadership in the field of liquid-based cooling solutions. By successfully transferring our extensive expertise to hydrogen-based mobility solutions, we are expanding our spectrum of applications and, thereby, also our product portfolio,“ says Michael Finger, member of the Board of Management of technotrans SE. Follow-up projects are possible.
Osnabrücker local public transport (ÖPNV)
technotrans has been supplying cooling solutions for the charging infrastructure of the local public transport sector in Osnabrück since 2017. Until the end of 2021, approximately 80% of the fleet will be battery-powered. High level of energy efficiency and a low level of noise emissions: A strong argument in favour of the technotrans technology is its energy-saving design: chillers made by technotrans require rather little energy for removing the heat that is generated.
technotrans achieves this high level of efficiency by using speed-controlled components for its cooling solutions. These systems provide power even during partial load operation and are characterised by an astonishingly low noise level. This is important as there are strict noise restrictions for residential areas. When it comes to cooling, the charging infrastructure manufacturers increasingly rely on technotrans as a competent partner. A long-time customer explains: "technotrans always perfectly adapts its systems to our systems. This is a huge advantage! And:." we get everything from a single source - from the concept study to the development of the technology to the fully installed solution."
Outlook The future
Also in the private transport sector electric vehicles are expected to become the preferred means of transport in the long run. However, for this vision to become reality, not only high-performance batteries but also a suitable fast-charging infrastructure is of utmost importance. Numerous vehicle manufacturers now rely on high-power charging (HPC) it enables full charging in just a few minutes. The charging cables, however, need to transfer a large amount of power (approx. 300 to 400 kW) in a very short time. This results in the development of excessive heat due to the line resistance. To ensure the proper cooling of copper conductors, they are embedded in special hoses through which a coolant circulates. The necessary cooling units are usually integrated in the charging station and use either a passive cooling concept based on the ambient air or an active concept with a compressor.
Thanks to its extensive expertise and leading technologies, technotrans has a lot to offer to the e-mobility market and also has a great potential for the fast and efficient evolution of its products. In just a few years, technotrans has firmly established itself as an innovator throughout the industry and will continue to gain additional market share.