Inland shipping

Inland waterway transport already covers a significant proportion of freight transport volumes. Its further expansion is part of the European strategy to shift freight transport from road to rail and waterways.1 Electric propulsion concepts represent important approaches for climate-neutral inland shipping. This is accompanied by a considerable improvement in air quality. Hybrid solutions with hydrogen and batteries are currently in the spotlight.



1 BMWI (2018): Maritime Forschungsstrategie 2025.
Link ↗ (accessed 21.09.2021).

Relevance of the field of application

Inland shipping is an important transport medium for freight traffic. More than 197 million tonnes of goods were transported on 7,700 km of waterways in Germany in 2018. This corresponds to just under 5 % of the total goods transport in Germany. Over 90 % of this was accounted for by the goods divisions ores, petroleum products, fossil fuels, chemical products, agricultural and forestry products, secondary raw materials, waste and metal products.2

It is true that the CO2 emissions per tonne-kilometre are 75 % lower than for truck transport. However, the pollution caused by air pollutants (nitrogen oxides and particulate matter) per tonne-kilometre is at a similar level due to the fuels and engine technology used. In view of the fact that the loading capacity of an average inland waterway vessel is equivalent to that of over 100 articulated lorries,3 it is not surprising that air pollution from ships has increasingly become the focus of public debate, especially in cities with inland ports.

In the course of the tightening of European legislation to reduce the environmental impact of inland shipping, the share of gas propulsion (LNG) in new shipbuilding is increasing.4 The use of electric propulsion, on the other hand, is still in its infancy, but promises advantages in the medium term in terms of climate neutrality and economic efficiency.


2 Destatis (2020): Güterverkehr - Beförderungs­mengen nach Güterabteilungen und Verkehrsträgern in 1.000 Tonnen für Eisenbahn, Binnen­schifffahrt, Seeverkehr und Straßenverkehr inländischer Lastkraftwagen. 
Link ↗ (accessed 21.09.2021)

3 Zentral­kommission für die Rhein­schifffahrt (ZKR) (2018): Jahresbericht 2017. Europäische Binnen­schifffahrt – Marktbeobachtung. 
Link ↗ (accessed 21.09.2021)

4 EU (2016): Verordnung (EU) 2016/1628 vom 14.09.2016. 
Link ↗ (accessed 21.09.2021)

Use of battery storage

There are two different basic concepts for the use of battery storage in the propulsion technology of inland vessels: battery-electric and hydrogen-based drives. In battery-electric drives, the entire drive energy is carried in traction batteries. In hydrogen-based drives, hydrogen is converted into electricity by means of a fuel cell, which is then used for the electric drive via a battery.5 In addition to the propulsion energy, the energy for the on-board electronics can also be provided accordingly on the ship. This is then usually done by using independent batteries and thus detached from the traction battery. The loading and discharging process in port with the corresponding machinery is also occasionally the subject of electrification measures.

The considerations of Holbach offer an orientation to the possible applications of electromobility on the water.5 The hydrogen concept presented by him requires 3 fuel cells with an output of 100 kW each as well as a battery capacity of 2 x 1,160 kWh for propulsion and 2 x 116 kWh for the on-board electronics.5 For bridging short ranges (in the range of 65 km/day) and medium operating times (8 hours/day) he recommends purely battery-electric drives, for medium ranges (100-130 km/day) and longer operating times (16 hours/day) hydrogen-based drives. Depending on the infrastructure, a charge-stop strategy is recommended for the latter for ecological and economic reasons, which uses repeated intermediate charging of the battery to reduce fuel cell use.

Batteries can also be used in hybrid concepts with fossil fuels. Here, diesel generators produce electricity for the ship's electric motor. By decoupling the mechanical connection between the ship's engine and the ship's propeller, which is common in combustion engines, and by using a buffer battery, the entire system can be operated at optimum efficiency. In this way, fuel consumption as well as pollutant emissions can be reduced to a considerable extent.6


5 Holbach, Gerd (2020): „Elektro­mobilität auf dem Wasser mittels Brennstoffzelle und Wasserstoff am Beispiel des Schubbootes ELEKTRA", Vortrag anlässlich der Innovations­konferenz des Projekts "E-Mobilität in Binnen- und Küsten­schifffahrt" am 27./28.01.2020.
Link ↗ (accessed 21.09.2021)

6 Vandel Jensen, Helge (2017): Hoch­effiziente Hybridantriebe in der Binnen­schifffahrt, AUTOCAD & Inventor Magazin 
Link ↗ (accessed 21.09.2021)

Performance requirements

Inland shipping is increasingly becoming the focus of public discussion due to its negative environmental impact. Environmental compatibility therefore also plays a central role in the battery technology used. In view of the average operating life of the vessels, investment security in conjunction with high safety requirements also play a key role. The batteries used should last at least 30 years and present the lowest possible risks in terms of flammability and explosion.

The fast-charging capability of the battery determines how much power can be charged for the onward journey during the discharging or charging process in port. It is thus an important factor for route planning.


Market outlook

Around 90 % of Europe's foreign trade and 35 % of its inland trade is carried by sea and inland waterways.1 In Germany, inland shipping accounts for just under 5 % of all goods transports.2 The market volume for battery storage results in particular from the size of the shipping fleet as well as the replacement rate - which in turn is heavily dependent on the relevant environmental legislation. In Europe, there are currently over 15,000 inland waterway vessels used for freight transport. While the total number has steadily decreased since 2005, the tonnage of vessels has increased. This is due to smaller vessels leaving the fleet and being replaced by larger vessels.7

If all European inland waterway vessels were converted to fuel cell propulsion, this would result in a battery demand of 38 GWh on the basis of Holbach's waterway concept (see above). Depending on the inclusion of purely battery-electric drives, this market volume would increase significantly.

7 Zentral­kommission für die Rheinschiff­fahrt (ZKR) (2020): Jahresbericht 2019. Europäische Binnen­schifffahrt – Markt­beobachtung. 
Link ↗ (accessed 21.09.2021)