Port and terminal operators expect more tugs to use power from shore and batteries during transit between towage tasks
Port authorities and operators are building environmental and sustainability strategies that will require tugs to be powered by batteries and shore power.
These strategies aim to cut emissions from terminals and harbours to improve air quality and reduce ports’ carbon footprints.
During Riviera Maritime Media’s Maritime Air Pollution, Europe virtual conference on 20-22 October, representatives from port authorities and owners explained their drives to lower emissions and improve air quality, especially in harbour and terminal zones close to residential areas.
Ports are planning to spend tens of millions of euros to provide shore power from renewable resources to ships docking at cruise, ferry and container ship terminals. In some cases, this power will be available to tugs providing support to ship dockings.
Hamburg Port Authority director shore power Hanno Bromeis said €10M (US$11.6M) had already been spent on shore power, also known as cold ironing, on one facility at Altona cruise terminal. It plans to invest another €95M (US$110.6M) on shore power facilities at six more terminals serving cruise and container ships.
Mr Bromeis said these facilities could be available for electric-powered tugs operating in the port. “With our second and third wave enabling shore power, it could be sensible for tugs to use this,” he said. “A mobile solution could be useful.” This could also be provided for electric-powered pilot boats.
Port of Valencia naval architect and marine engineer Raúl Cascajo agrees tugs could run on electric power with batteries on board for transits and during standby. “To reduce emissions from port service vessels, they should run on electric,” he said.
“When tugs sail to ships and around ports, they produce emissions – we need to tackle these,” said Mr Cascajo.
Port of Valencia, which manages terminals and harbours in three ports including Gandia, Sagunto, provides 550 kW of shore power to tugs with hybrid or electric propulsion from one facility in Valencia.
During the session, Port of Helsinki head of sustainable development Andreas Slotte suggested another solution that would not require investment in hybrid propulsion or onboard batteries.
“Biofuels would be a good solution for tugs and does not need heavy technology or investment,” said Mr Slotte.
In the Port of Zeebrugge, electric power will be provided to ship assistance tugs operated by Boluda Towage Europe. This was confirmed when Boluda gained a five-year concession extension to provide towage in the port.
As part of the tender, Boluda committed to reducing emissions by updating the tug fleet to IMO Tier III emissions compliance, which involves removing NOx and particulate matter from emissions.
Boluda also said “electric power connections would become the norm for moored tugs, enabling them to turn off their engines when they are idle and during the crew’s rest period”. Port of Zeebrugge is investing (along with Engie and ICO) €55M (US$64M) to install 11 wind turbines on the ICO Windpark, capable of generating 44 MW of power for moored vessels and terminal infrastructure.
In Sweden, Port of Luleå is an early adopter of electric-power and hybrid propulsion. It not only provides shore power but owns a powerful hybrid tug with onboard batteries.
Port of Luleå technical manager John Sundvall described why it invested in newbuild ice-breaking harbour tug, Vilja, during Riviera’s Hybrid and electric tug viability: the future’s bright webinar, on 3 September.
Gondan Shipyard built this tug in Spain to a Robert Allan TundRA 3600 design with Wärtsilä-supplied hybrid propulsion and integrated power systems.
Mr Sundvall said the reasons for investing in a hybrid tug were to reduce emissions during transits to towage jobs and to use the clean energy available at the quayside.
“A key benefit with our hybrid is low emissions during missions, when we may only need to use one engine,” he said. “We needed a lot of power, but full power was seldom used.”
Another benefit is the peak shaving function when power loads are uneven, as Vilja operates through ice in the Port of Luleå. “We can start the engine using electric and there are different modes of operation,” he said. “We have clean energy available with the possibility of charging at the quayside.”
Batteries on board provide a boost to Vilja’s power, increasing its bollard pull from 90 tonnes to 100 tonnes for heavy towage in ice.
Mr Sundvall then explained why Wärtsilä was selected. “Because we wanted one supplier for the whole system,” he said. This included the main engines, generators, batteries, electric motor and the power management system. Power from this system feeds a pair of Kongsberg US355 thrusters.
Vilja’s environmental and financial performance has been higher than anticipated. “We are getting better consumption savings and lower costs than anticipated,” Mr Sundvall said. “We are only using diesel during ship assistance and we are getting a better range during transits, when on electric mode, than we expected.”
California terminal tugs
In the US, Port of Los Angeles and Long Beach has implemented its plans to improve air quality through investing in reducing emissions from terminals, docking ships and port service vessels. Cargo marketing manager Marcel van Dijk said it sets environmental requirements and provides incentives to tug owners.
“The port has a Clean Air Action plan that will address all harbour craft that operate in our port,” he said. “We have several tugboat companies working in our port.”
He stressed the authority was the port landlord and did not operate any terminals, nor did it set any design or performance criteria.
A federal and [California] state phase-in of more stringent marine engine emissions standards has led to investment in tugs to Environmental Protection Agency (EPA) Tier 3 or 4 emissions levels. There has been financial assistance to offset the cost of deploying cleaner harbour vessels.
These ports have funded the construction of electrical infrastructure for tugboats to use shore power when they are tied up at berth. The main tug operators, Crowley and Foss, have shore power capability at berth and it is common practice to turn off engines when tugs are at the quayside. These operators have invested in newbuildings with EPA Tier 4-compliant propulsion.