Teekay shuttle tankers to use VOC fuel
Harnessing waste gasses and deploying battery technology could cut LNG fuel consumption by 34% on Teekay shuttle tankers
Teekay is to employ batteries and volatile organic compounds (VOC) as fuel for a series of up to four shuttle tankers after receiving a NOK132.9 million (€14.0 million) grant from Norway’s state-owned innovation platform Enova.
New technology developed by Teekay and Wärtsilä mixes VOCs – waste gasses emitted from crude oil during loading, unloading and storage – with LNG to be used by the ship’s engines. The use of VOCs, combined with the first ever battery installations on a shuttle tanker, is expected to cut LNG use by 34%.
The ship owner told The Motorship that the VOC ‘boil off’ from the oil cargo will be stored in a tank before it is mixed with LNG, with the new technology controlling the methane number of the mixture before delivering it to the engines. Teekay has selected Wärtsilä 34DF engines for the project, configured for diesel-electric propulsion and also featuring waste heat recovery technology for further fuel efficiencies.
A battery pack comprising two 250kWe batteries will be used, and the vessels will feature a ‘battery safe’ class notation. The company confirmed that the batteries will be used for peak shaving – enabling engines to run at optimal load by taking excess load when needed and charging from engines when power demand is low. Shore power connections will not be included.
Ingvild Sæther, president and CEO, Teekay Offshore, said: “We see this as a unique opportunity to introduce a shuttle tanker that reduces emissions and fuel consumption, thus reducing both climate impact and operating costs.”
The 277m loa, 130,000dwt vessels will have an oil cargo capacity of approximately 870,000 barrels. It is expected that the order for up to four vessels will be placed within the next few months, with first vessel to be delivered in 2019.
Nils Kristian Nakstad, managing director, Enova, said: “This is a very good climate project where Teekay is seizing a waste problem and making it into a resource. It is also an important step forward for the battery revolution at sea. The fact that batteries are now being used on such large and energy-intensive ships paves the way for using batteries on even more ship types.”
Enova and Teekay estimate that half of all offshore oil production in Norway and the UK is transported to land using shuttle tankers, with about 40% of the fleet ready for replacement.
Teekay has been exploring the use of VOCs in a sub-project of the Green Coastal Shipping programme coordinated by class society DNV GL. Wärtsilä has also been developing VOC technology: in 2016 the company used a 1MW gas reformer to convert the liquefied VOCs from a shuttle tanker into natural gas, which was used to power a Wärtsilä 6L20DF engine at test facilities in Bermeo, Spain.