Rail is already the greenest, eco-friendliest mode of transportation. But combatting climate change calls for new technologies that consume less energy and avoid harmful emissions. New drive technologies from Knorr-Bremse’s Rail division represent genuine alternatives to the diesel engine.
Sometimes raw data paints the clearest picture. According to Germany’s Federal Ministry of Transport, some 37 percent of the country’s local mass-transit trains still run on diesel drives. So clearly there’s still plenty of room to improve the sector’s carbon footprint – and here are a couple of the most promising options for doing so.
Alternative drive technologies from Knorr-Bremse: innovative, practical
One option is to electrify all rail routes. To date, only about 61 percent of Germany’s rail kilometers have been fitted with overhead lines. Following the coalition government’s latest agreement, this is expected to rise to 70 percent by 2025. What’s more, over the next few years, both the government and rail operators are looking to invest around EUR 86 billion in the modernization of tracks, bridges and signaling systems. The main aim is to run more electrified – meaning, eco-friendly – trains over the same track distance. But in truth, it’s not always easy to electrify rail tracks, which is why other eco-friendly options are required, as in: alternative drive technologies.
Knorr-Bremse headed off in this direction at an early stage, which is why the company is now a major player in this area. First, as a well-established partner to rail vehicle manufacturers and operators who continue to rely on customized subsystems for their battery- or hydrogen-powered vehicles, from brakes through to train control & management systems (TCMS). But above all, as a provider of unique concepts for innovative, yet highly practical alternative drive solutions.
Playing a specialist role in the transition from diesel to electric
Many of the complex factors involved come together in Düsseldorf, Germany, which is where you’ll find Kiepe Electric – a Knorr-Bremse company that owes its stellar international reputation to its electric drives and powertrains. And now that the shift from diesel to electric has become so important, especially in mass transit, Kiepe is in the spotlight as one of the leading specialists in this area.
Take, for example, Kiepe Electric’s technology for bridging the transition to climate-neutral trains. Here, Knorr-Bremse has come up with a compelling solution for making existing diesel-powered rail vehicles much climate-friendlier in the future. Essentially, this involves modernizing them and turning them into full-hybrid trains. On electrified routes, the train draws its power from the overhead lines; on non-electrified sections of track, the control unit swaps over to the train’s onboard traction battery, with the diesel engine as a fallback option. The technology has enormous potential – and not just because of the relatively high proportion of non-electrified tracks in Germany. Depending on the route profile, many operators are now running trains on less than 20 percent diesel or even, in the right conditions, exclusively on all-electric power.
A similar concept, IMC technology, is also available for e-buses. Standing for “In-Motion Charging”, IMC represents a hybrid concept for this whole category of vehicles. On electrified routes, the (trolley)buses run on electricity from overhead lines – while at the same time recharging their onboard batteries. And when they encounter a section of road without overhead lines, the buses simply switch over to battery power. To put this in perspective: a 12-meter bus fitted with what is currently the most powerful system on the market, Knorr-Bremse’s IMC500, only needs to be in contact with an overhead line for about 15 percent of its time on the road.
Kiepe Electric has just developed an enhanced version in the form of an e-drive concept that includes traction batteries. Thanks to the sophisticated interplay of multiple Kiepe technologies, buses can now charge their batteries at rates of up to 750 kilowatts, enabling them to recharge in a matter of minutes whenever the bus takes a break at a final stop or terminus (and buses are legally required to take breaks). This avoids one of the major headaches associated with existing battery-driven buses, which often need to recharge overnight. What’s more, the concept and underlying technologies are modular, scalable, and suitable for any make of bus.
Another attractive option involves converting heavy-duty specialized vehicles running on diesel-hydraulic drives – including vehicles intended for trackside loading and unloading operations. In diesel-hydraulic drives, the engine power isn’t delivered directly to the powertrain, it’s transferred over a hydraulic system. This avoids a basic issue – the fact that diesel engines can’t start under load. So Kiepe Electric offers an alternative solution: convert diesel-hydraulic powertrains to fuel-cell or battery-powered drives.