Context of Transport Climate Action
In around 2012, the Norwegian Ministry of Transport launched a competition for the most environmentally friendly car/passenger ferry to cross the Sognefjord near Bergen. The Ministry wanted a ferry with low noise and few emissions so the environment was impacted as little as possible.
A battery-electric ferry with high-power, charging at each quay, won the contest. The fast charging system included the installation of a battery buffer system at each quay in order to facilitate high power charging of the ship without overloading the relatively weak grid. The ferry is operated by Norled, a privately owned ferry company.
The electric ferry named Ampere entered into service in early 2015. It crosses the Sognefjord about 34 times a day (17 round trips) and has a capacity of 360 passengers and 120 cars. The 6 km crossing takes 20 minutes. The 1,000 kWh Li-ion battery system of the ferry is charged at each quay for about 10 minutes.
90% of the electricity in Norway is produced from hydro (water power), which is virtually free of pollutant and CO2 emissions. This contributes a lot to this overall environmentally friendliness of this concept.
The ferry owner and operator is Norled. The ship was build by the Norwegian Fjellstrand shipyard. For an electric ship, it is very important to reduce the energy consumption as much as possible. This is important to limit the battery size and charging power to reasonable values.
A reduced of energy consumption of about 30% was achieved by designing a slender, lightweight aluminum, catamaran hull and by limiting the operational speed to about 10 knots per hour (18 km/h).
The CO2 reduction with the electric driven, light-weight, ferry is estimated to be 2,150 tons annually or a reduction of about 95% compared to a conventional diesel ferry. The light-weight ferry uses 50% less propulsion energy than a conventional steel ferry. The fuel costs are only 20% of the operations.
The ferry will use about 1 million kWh of electric power.and near zero emissions hydro-electric power in Norway is widely available.
Potential for scaling up
Almost all ferries up to this size and with these trip characteristics (frequent and short crossings) are judged to be suitable for battery electric propulsion.
In Norway, al least 80 other ferries on 60 different crossings, are thought to be suitable for electrification.
Electric propulsion is quite economically attractive as the pay back period is estimated to be around 5 years.
There are several other examples of battery electric ferries in Europe. These include:
- Le Ferry Boat: Marseille: 45 passengers and in service since 2003.
- Movitz Stock-holm: 100 passengers and in service since 2014.