The WLE train ran between Lippstadt and Warstein, in northwestern Germany. Along the line, roughly 30 kilometres long, WLE usually moves construction material as well as beer and also provides single wagonload services. The company has been at the forefront of DAC testing, as it carried out the first commercial tests for traditional DAC last summer.

DAC tests recap

Since the beginning of 2026, the amount of tests announced and launched in the context of DAC escalated. Other than the WLE tests, in cooperation with coupler manufacturer Voith, 2025 also saw DAC tests in Sweden to assess the coupler performance under extreme weather conditions.

This year is the turn of Austria Rail Cargo Group, which is running similar tests to the ones done in Sweden. Large-scale commercial tests are scheduled for 2027, where seven trains will be equipped with the coupler and will run in nine different countries with raw materials or carrying out intermodal services.

Currently, more preliminary DAC tests are being carried out. The first ever commercial pilot was launched in Germany in the summer of 2025, while in Sweden the ability of DAC to work under extreme weather conditions was tried. Currently Austrian Rail Cargo Group is testing DAC on different types of wagons and will continue to do so for the whole of 2026.

The DAC cost problem

One of the main points raised by DAC critics is the cost and who will have to bear them. Given the lack of clear guidelines from EU institutions, estimations vary and seem to be increasing each time they are reviewed. Currently, many agree that equipping a unit should cost between 22,000 and 25,000 euros, while the total cost of the project is somewhere around 15 billion euros.

Level playing field

One of the issues with paying for DAC is that smaller players might struggle to find the funds, especially since the EU has not yet decided how much it will cover for the rollout phase. “With at least 15 billion euros in funding needed, I assume that subsidies and grants will cover one-third of the costs maximum”, he said. However, Pasternak added that his proposed model would be the same for all companies across the EU, whether they are large rolling stock lessors or small industrial entities.

The plan would be to create a non-profit DAC rental company for all users in Europe. “Based on EU guarantees and our AA rating as a non-profit institution, we have calculated that we could offer a DAC in a hire-purchase scheme over 20 years at 3.49 EUR per day. This would massively reduce the initial investment costs”, he explained. With hire-purchase schemes the ownership of the product would go to the final user once the debt has been settled.

Tests continue

While the financial aspects of a large-scale DAC deployment are far from being a certainty, tests on the ground are ongoing in different parts of the Old Continent. Austria and Sweden are leading the way, with pilots for intermodal and bulk transport with DAC-equipped trains in harsh conditions. Large-scale tests are scheduled for 2027, involving Germany, Austria, Italy, Luxembourg, Slovenia, Sweden and Norway.

The pilot in Sweden also aimed at testing DAC under extreme weather conditions, but with a much heavier train moving steel. After country-specific tests, next year it will be time to take it a step further with large-scale ones. The plan is to equip 250 wagons and 15 locomotives with DAC and have them run throughout the Old Continent.

Different wagons and different couplers

The wagon types which will undergo testing are Eanos, Sgnss, Shimmns (4668 & 4676), Habbiins, Talns and Faccns, as well as two Siemens Vectron locomotives. Each wagon will be equipped with a CCU (Consist Control Unit), while the two locomotives with an LCU (Lead Control Unit). These are key components of the DAC, as they provide power supply throughout the train, enabling functions such as the automated brake test or the automated uncoupling.

These tests will also be an opportunity to assess interoperability between couplers from different manufacturers. More specifically, the couplers will come from Voith, Knorr Bremse, Wabtec and Dellner. The wagons will be equipped with 44 couplers. “Additionally, the two Vectron locomotives have four hybrid couplings, enabling them to haul wagons equipped either with DAC or conventional screw couplings”, RCG said.

Waiting for large-scale tests

These DAC Demo tests are part of Europe’s Rail Joint Undertaking Flagship Project 5 (FP5 – TRANS4M-R). They can be considered as the first step towards the large-scale Pio-DAC tests which will start in 2027. “The PioDAC Trains are the next evolution phase and shall start afterwards with a higher maturity of DAC technology and operate additionally under commercial conditions”, the RCG spokesperson pointed out.

“This shared financial responsibility highlights that PioDAC is an industry-driven project aimed at preparing the market introduction of DAC under real operating conditions, rather than a purely theoretical research exercise”, he underlined. The project is coordinated by Trafikverket and brings together railway undertakings, wagon owners, workshops, industrial partners and shippers from across Europe.

The large-scale tests

The first phase concerns the installation of roughly 500 DAC units “on approximately 250 freight wagons and 15 locomotives”, Radke said. This phase will be overseen by the VPI service company VERS, which coordinates installation on freight wagons and monitors maintenance aspects throughout the project. From 2027 onwards, DAC-equipped trains will run across Europe, carrying different types of cargo.

At the same time, economic validation and the development of a standardised rulebook are addressed within the project framework, ensuring that technical, operational and regulatory aspects are considered in parallel. The International Union of Railways (UIC) contributes to the development and refinement of the standardised rulebook, ensuring that operational experience from the project feeds directly into European-level standards.

“Large-scale means that DAC is tested in regular commercial operations, embedded in existing logistics chains and railway processes”, Radke added. “This includes cross-border services, different traction concepts, various wagon types, diverse commodities and a wide range of environmental and operational conditions.” By operating in day-to-day commercial service rather than isolated pilot settings, the Pioneer DAC Trains are expected to generate robust evidence on technical performance, operational reliability and maintenance requirements.

“Cross-border operations will take place, among others, between Austria and Hungary, Luxembourg and Germany, and Germany and Poland, complemented by domestic routes”, Radke pointed out. “The mix of operators, commodities and operating concepts is intended to ensure that DAC is tested under realistic conditions across Europe”.

What to do with the results?

“The primary objective is to demonstrate that DAC-equipped trains can operate reliably and safely in commercial service across Europe”, Radke stated. Operational and maintenance data will be systematically collected and analysed over the project duration to create a solid evidence base covering performance, robustness and cost implications. The data gathered will be used to support a coordinated, EU-wide DAC migration.

From the VPI’s perspective, such coordination is essential to avoid fragmented or nationally isolated approaches and to safeguard interoperability in European rail freight. In addition, “the intention is that the trains can continue operating beyond the project phase and remain in productive service.” At the same time, Radke stressed that the immediate priority is to use the project results as a sound technical and operational foundation for a future Europe-wide decision on the introduction of the DAC.

Persisting doubts

Despite this development, DAC is still a controversial initiative. Its cost, for example, continues to be the subject of many debates. The most optimistic estimates say that the migration to DAC across Europe will cost 8,5 billion euros, while the highest are set at somewhere between 20 and 30 billion euros.

And a probably more important question is who is going to have to pay for this ginormous amount of money. Some argue that the rolling stock industry should absorb the costs, while others think that EU institutions should cover all expenses given the European reach of the initiative. Which takes us to the final issue.

Does DAC really need to be deployed on every rail freight wagon that circulates in Europe? Even DAC ambassadors acknowledge that a full migration will likely never be obtained, especially given the estimated costs. On the other hand, specific segments such as single wagonload could benefit from the technology.

Specifics of the tender

“The action to be procured will involve the research, analysis, development of engineering solutions, and possibly testing for a limited number of locomotive types” for both DAC and ERTMS, the document added. The estimated value of the contract is three million euros, with a duration of 48 months – 12 set initially with the possibility of renewing three times.

The contract also comes with an interesting section, which claims that the companies selected for this tender will be allowed to provide similar services without “prior publication of a contract notice”. In other words, DB Systemtechnik will sort of have priority when it comes to other similar projects, as they can be assigned 50% of the new contract without a new tender or notice.

Yet, EDDP does hint at some requirements to make DAC a success, which is not a priori guaranteed. Among those requirements are coordinated migration plans, funding and financing models. It is exactly the issue of money where controversy is abundant.

For the rail freight sector, a key priority in the coming years will be to reduce costs and improve profitability. As it currently stands, the industry is barely profitable (if at all). The introduction of new technologies causes some anxiety among companies, who are afraid that higher costs will force them to charge higher prices, ultimately making them lose valuable customers. For this reason, the cost of DAC is a vital factor determining the support of the rail freight sector for the technology.

Existing estimates

There are various sums of money circulating as regards to the cost of DAC. Those range from several billion euros to a couple of dozens of billions. What sets the cost pictures apart is how much of the likely expenditures they incorporate in their estimates, as well as the base version of DAC to be implemented.

According to EDDP’s DAC factsheet, a total of 8,5 billion euros would be needed to migrate Europe’s 500,000 freight wagons to DAC. That means that the cost per wagon would amount to some 17,000 euros. This number does not yet include the retrofitting cost for locomotives, which is expected to also comprise a significant part of the total required investment. That cost estimate is on the low end.

The versions of DAC

That has to do with the base scenario that EDDP envisions: the implementation of DAC type 4 (DAC4). DAC4 includes automatic air pipe, power and data coupling, ECP brakes and partially automated uncoupling. By contrast, DAC3 does not yet include data coupling, whereas DAC5 adds full-fledged remote uncoupling. The higher the DAC version, the more technologically advanced and therefore expensive.

An early study by EY and Ineco (2023) estimated the cost for DAC migration to be around 10 to 11 billion euros. In the short term (first ten years of DAC use), DAC would cost 10,9 billion euros and accrue 8,4 billion euros in benefit. This would apply in the case of an implementation of DAC5 in combination with an automated brake test device.

EY and Ineco did concede that there was still much unclear about the cost of the coupling device, locomotive installation cost and maintenance cost – leaving uncertainty about potential expenditure increases.

It must be noted that the EY/Ineco study foresees substantial benefits in the long term, were DAC5 to be implemented in combination with the automated brake test device, automated wagon inspection and an automated parking brake. The rail freight sector would incur more costs on the short term, but in the long term, benefits greatly outpace costs.

Swiss DAC estimates

The numbers mentioned by EY/Ineco and EDDP could be said to be on the lower side of expectations. According to market sources, Swiss rail freight operator SBB Cargo has said that the cost for a single wagon conversion was around 40,000 to 50,000 euros. When taking into account German rail analyst SCI Verkehr’s estimate of 460,000 necessary wagon conversions, that would already lead to more than 20 billion euros in expenditures for wagons alone. It must be pointed out, however, that it is unclear if SBB Cargo’s estimate envisions DAC4, DAC5 or any other additional investments.

The Federal Office for Transport (FOT) of Switzerland (known to be a very pro-DAC country) in 2023 came out with its own assessment of DAC costs. In one of its CBA scenarios, the implementation of DAC4 would go hand-in-hand with the automated brake test, automated technical wagon inspection, an electrical energy system and communication system. In another scenario, DAC5 would be implemented, together with all of the above, plus an Ep-brake system, a video stream from the last vehicle, automated train integrity control and condition-based maintenance.

Market sources tell RailFreight.com that, in their view, the DAC5 scenario is the most likely cost picture. There would be “no point to implement any lower level”. DAC5 and additional functionalities would yield the highest total benefits, which is also underscored by the EY/Ineco study. During a timeframe of 30 years, it would provide 67 billion euros in benefits, as opposed to 24 billion in costs. Implementation of DAC4 would mean that wagons would need to go back to the workshops again in a number of years for further upgrades, market sources say.

A worst case scenario for DAC costs?

What’s more, FOT’s scenario for “difficult” retrofits (at least for locomotives) will likely come true, according to market sources. That is due to differences in locomotives built in the west and the east, the need for extra power generation on-board, as well as the extra weight that needs to be spread out over the axles locomotives axles, for example.

The result, according to FOT, would be a locomotive retrofitting cost of around 2,7 million euros per unit. In a more favourable scenario, it would only cost around 100,000 euros. These factors have led skeptical rail freight experts to expect a 20-30 billion euro cost picture for a Europe-wide implementation of DAC5.

In short, there is no clear-cut answer as to how much DAC is going to cost in reality. It highly depends on the version of DAC to be implemented. What’s more, the initial capital expenditure is high – meaning that benefits will only accrue over time. That is an obstacle for rail freight companies, which cannot carry that burden on the short term. It seems that DAC can only become a reality with significant, if not complete, EU funding. The fate of DAC and the extent of its implementation likely depend on the vision of EU politicians.

Only automatic brake test for now

It was not specified on which route the test train will be running, but Voith did offer some details on the tests themselves. The wagons will be connected via the e-coupler, which will provide continuous power and data supply, which will enable automatic brake testing. “Further functions, including automatic detection of train length, wagon sequence and train integrity, are planned for later operation”, the company added.

Westfälische Landes-Eisenbahn

WLE is part of Westfälische Verkehrsgesellschaft, a group managing various transport company in the Westphalia region, in northwestern Germany. The company owns and operates around 120 kilometres of network, moving around 1,4 million tonnes annually. Its main business revolves around limestone and cement. WLE also handles a service for the Warstein Brewery, taking its products to Munich and Hamburg.