“As the founder of Corvus Energy in 2009, I brought the marine industry a world first – a purpose designed energy storage solution to meet the needs of the marine customer. In the years following my departure it is apparent the industry is learning through failure, yet failure is the best teacher. Corvus’ failures taught us a lot and we treat it as a learning experience. As we move forward with PBES, we start with a clean slate of technology and grow the industry with a clear focus on safety, performance and value for our customers.” Brent Perry, CEO, PBES 


Translated version of the Norwegian TU article “Vision of the Fjords” published September 5, 2016, by Tore Stensvold – see original here.

The unique tourist vessel “Vision of the Fjords” is an innovative ship with hybrid drive. Forty meters long, Vision of the Fjords runs between Flam and Gudvangen in Sogn og Fjordane. During transit stages yesterday the Carbon fiber catamaran ran with a diesel generator and as soon as it entered the UNESCO’s World Heritage site area, switched to battery power..

Favourite for an award!

Now the ship favourite for the coveted title Ship of the Year – Ship of the Year 2016 award ceremony will be in Hamburg on Wednesday 6 September.

seasight_foto_emil-rasmussen-br-aa-1000x481Even though engineers and visionaries get excited about the technology, it is the design that has people taking notice.

– It is a paradox. We are known for building fast catamarans. However, we have never seen so much attention as after we launched Seasight just over a year ago, says CEO Tor Øyvind Aa.

Normally we build catamarans in carbon fiber that go 25-35 knots. Seasight-catamaran is built 8 knots and maximum 19.5 in transit. In tourist pacing mode of 8 knots, the battery pack from the Norwegian ZEM and energy management system from ABB does the job with CCP, controllable pitch propellers.


Approval of the battery propulsion system was a more complex process than initially envisioned. Plans for Seasight were well underway last autumn, but NMA had long questioned the batteries for safety on board passenger vessels.

The Canadian battery manufacturer Corvus has been the initial marine battery solution. They took up the challenge as the first manufacturer for Seasight, in August 2015 they started the three-week test program at SP Technical Research Institute in Borås. The goal was to prove that a possible failure with a fire in one cell, so-called “thermal runaway”, would not spread. Representatives from the passenger department of NMA were presented.

The tests went as planned, says Hillersøy to TU. Corvus confirms this on their website, where they talk of good feedback from classification societies and Authorities on tests. With certain modifications, the battery testing ended with a bang. ”It was an accidental event. It was not planned” says Hillersøy.

Explosion Confirmed

Some people have characterized “the event” as an explosion. SP at Boras confirms that not everything went as planned, but refers to Corvus for details. Technical Director David Lokhorst in Corvus confirms the explosion and that no one was hurt. In a long email to TU, he describes the comprehensive test setup with nine tests where battery management system (BMS) was set aside to force mistakes. Lokhorst says they confirmed that the “thermal runaway” was handled as intended. However, in one of the tests the gas was ignited unintentionally. “The tests we performed demonstrated that the batteries and our control systems work, but ventilation, the structure of the battery compartment and how to act on incidents needs additional focus” writes Lokhorst. He understands why NMA decided to issue new regulations to the industry.

New security checks

Armed with even more critical questions regarding fire and explosion safety, NMA went back to Haugesund. Hillersøy arranged a meeting with all market participants; battery manufacturers, suppliers, system integrators, classification authorities and shipyards to evaluate results after tests in Sweden. It was obvious to everyone that more development and testing were needed to improve safety. Hillersøy and senior engineer Øyvind Skog have worked closely and well with the industry. “We find that the work done after the tests in Sweden has gotten battery technology further on” says Skog.


In Trondheim, the new battery factory PBES is under construction. The company is started by one of Corvus’ Founders, Brent Perry. Their focus is primarily safety, to prevent “thermal runaway” and fire, in their second-generation battery systems.

During this spring there was a series of tests performed on the Seasight batteries, including tests at the Norwegian army research institution. Technical Director of ZEM, Egil Mollestad, is a veteran in battery technology environment in Norway. He was pivotal in the development of Think. Mollestad says that the close co-operation with FFI has been important for them.

Vision of the Fjords

Operator: The Fjords – Passengers: 400 – Length: 40 – Width: 15 m- Maximum speed: 19.5 knots – Engines: 2x MAN 749kW + 2x Oswald PM electric motor 150kW – Transmission / propellers: ZF marine gear, West Mekan CPP .   Seasight will carry up to 400 passengers, and is built in carbon, a new material for battery based vessels. That got NMA alarmed.

– Carbon hulls created other requirements for cooling and ventilation, says Mollestad, who appreciates getting new challenges.

System specialists

He argues that ZEM stands behind an even better version of the second generation battery system. Zems Energy Storage Solution (ESS) battery cells are manufactured by LG in Korea and assembled by Nidec-ASI in France. “We specialize in battery systems. We will not deliver as many, but we will be the best. We are small and we show that we will provide. We do not give up before everything is in order with regulations and the systems work, says Mollestad.

The dialogue between the ZEM, DNV GL and NMA was close during the development of the propulsion system in Seasight. DNV GL worked with creating new class rules while NMD drafted regulations. On July 18th, NMA issued a letter where regulations were put into practice. The same day as the Seasight-vessel “Vision of the Fjords” was certified. Mollestad praises NMA´s work. “They have been very positive and proactive. They are helping to pull the Norwegian maritime community forward” says Mollestad.