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A computer-generated image of a cargo ship fitted with 'solar sails'
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Does shipping have a green future?

Chris Carroll

27th October, 2009

The aviation industry has its climate change plans, car manufacturers are working on 'eco' alternatives, and rail is considered top of the class, but what has the transport mode that delivers 90 per cent of goods to the UK done to improve upon its environmental credentials?

As an ethically conscious consumer - whether that means the odd jar of Rainforest Alliance certified coffee or the latest bamboo bicycle - the chances are that your products arrive in your home only at the end of a very long sea journey in a rather large container ship.

These vessels predominantly run on the dregs of refined crude oil: fuel oil, the heaviest, dirtiest fuel type, containing 2000 times the amount of sulphur compounds as that found in road petrol or diesel. The sulphur emissions alone are thought to be responsible for around 60,000 deaths a year across coastal parts of Europe and Asia, and although measures have been taken to reduce sulphur emissions, without further intervention that figure could rise to around 87,000.

The carbon footprint of marine fuel fares little better: shipping’s CO2 emissions are pegged at around 1 billion tonnes per year, contributing between 2 - 5 per cent of world greenhouse gas emissions.

Although shipping is widely recognised as the most ‘carbon efficient’ mode of commercial transport - a fair argument for preference over air or road freight - this shouldn't be taken to mean that shipping is 'green' business.

The industry itself has suffered severe criticism over its attitude towards environmental responsibility, and for good reason. With high profile environmental disasters such as the Exxon Valdez oil spill, and the less well-publicised but equally distribution of invasive species through the disposal of ballast water, it is viewed by many as a sector content to sit in the wings until a crisis manifests itself.

Change of course

Things have begun to change, however. In 2006 the global regulatory body, the International Maritime Organisation (IMO), began discussing what measures it might take in response to climate change.

Progress has been slow: to this day there are still no mandatory regulations or even voluntary standards in place to reduce carbon emissions from shipping, partly due to the discord between developed and developing countries over emissions trading and carbon taxation.

Many in the industry now hope that an array of technological solutions will give shipping the tools with which to reduce its environmental impact. Indeed, the IMO suggests carbon emissions could be reduced by as much as 75 per cent through technological and operational measures alone.

Tomorrow's ship?
 
Technology: Giant kites
Promoter: SkySails
How does it work?: Known officially as a 'towing kite propulsion system', SkySails' huge parasails are tethered to the front of a cargo ship and can pull the vessel forward with a force equivalent to between eight and 16 tons. This equates, the manufacturers say, to an annual average fuel saving of between 10 and 35 percent, rising to 50 per cent under 'optimal wind conditions'. Sophisticated machinery controls the kite, although some worry that the level of operator skill required may be beyond most commercial shipping crews.
 

Technology: Improved aerodynamics
Promoter: Greenwave
How does it work?: Greenwave's 'DRACS' project (Drag Reducing Aerodynamic Components for Shipping) has analysed which parts of a cargo ship's structure cause the most air resistance as it sails forward. The researchers discovered that the bridge and crew accomodation area (the large structure built at the stern of the ship) was a major problem, as were onboard cranes that remain on the deck at all times. The project suggests 'easy-to-fit' aerodynamic improvements to guide wind around the structures.
 

Technology: Harnessing the wind
Promoter: Greenwave
How does it work?: WASP - Wind Assisted Ship Propulsion - is Greenwave's attempt to harness a principle observed by 19th century German physicist Heinrich Magnus - that wind hitting a rotating cylinder creates areas of high and low pressure around its circumference, exerting a useful force. The principle was successfully tested in 1925 by German engineer Anton Flettner, although the design was found to be less efficient than conventional engines. Greenwave hopes that its re-envisaging of Flettner's rotors can provide some 13 per cent of the thrust needed by a cargo vessel, saving around 900 tonnes of fuel each year.
 

Technology: Improved hydrodynamics
Promoter: Greenwave
How does it work?: Another Greenwave proposal, the HYDRIS project (Hull Drag Reduction in Sail Assisted Shipping) has experimented with redesigning the bulbous underwater 'nose' of cargo ships, although fuel savings are thought to be limited. The company is now looking at air lubrication (see below).
 

Technology: Air cavity system/air lubrication
Promoter: (various)
How does it work?: A more established technology, with which engineers have experimented since 1970s, air cavity mechanisms aim to create layers of air under ship hulls to form a cushion on which ships can 'ride' with less resistance, reducing fuel consumption. The system is already used on certain vessles, but only works with specific hull designs, and new propellors are required to cope with the additional air in the water. An alternative system involves injecting air through thousands of tiny holes in the ship's hull to create a thin 'skin' of bubbles between the metal and water. This could again help to reduce drag, but the behaviour of air bubbles in surprisingly complicated, and under some circumstances they could actually make drag worse. Keep the tiny holes free of algae and barnacles has also proved a problem.
 

Technology: Solar sails
Promoter: Solar Sailor
How does it work?: Combining the two most abundant renewable resources - sunlight and wind - the solar sails are solid aerofoils clad with photovoltaic cells. Computer software developed by Solar Sailor helps the sails track both the wind (for direct propulsion), and the sun, which provides power to drive an electric propellor. Based on fuel savings observed in other hybrid systems - and on a prototype ship - the company claims fuel savings of between 50 and 90 per cent. This includes the savings using an all-electric drive system. The technology has yet to be tried on large ships, and is currently only feasible for ships that sail at speeds below 6 knots.
 

Notable innovations include a novel way to harness wind power from kites, an air-cavity system that would reduce a ship’s drag and a host of operational measures such as ‘slow-steaming’ that would mean for lower speeds and thus lower fuel consumption (see box, right). There are also scrubbing techniques that aim to clean up shipping exhaust, siphoning off carbon dioxide and nitrogen compounds from smokestacks, as well as more conventional measures being pursued such as improved hull design.

One of the most remarkable alternative power supplies again utilises wind, but not as you might expect. Greenwave, a not-for-profit organisation set up in 2006 and based in the UK, has re-examined a phenomenon known as the Magnus Effect.

Although first tested on a ship in the 1920s, the technique was soon dismissed in favour of the simplicity of cheap diesel. Today, the idea is gaining new currency. It involves thrust being generated from a rotating vertical cylinder positioned on a ship’s deck, a sort of mechanical sail. As air passes around the cylinder, opposing areas of high and low pressure are created on either side, generating forward movement. The developers claim that the additional thrust can account for 13 per cent of the energy needed to move the ship forward, and allows for the ship’s engines to be ‘throttled back’, saving an average ship - and not all ships will work with the technology - some 900 tonnes of fuel a year.

Water resistance

Major industry players have been moving in the right direction: Maersk Line, one of the world’s largest container line operators, has been performing a range of tests on carbon reducing measures and were rewarded for their endeavours at the recent Sustainable Shipping Awards ceremony in London.

But there is a sense that the industry has been enjoying such awards and conferences for several years without making much real progress. In 2006, I sat through a presentation at a shipping conference on the use of large kites to reduce fuel demand. At one point, the speaker made what was seen as an audacious prediction: that oil prices would 'one day in our lifetime' rise to over $100/barrel, making this technology eminently affordable. You could almost hear the biting of lips. And yet, fast forward a couple of years, and despite oil prices rising to almost $150/barrel, fuel saving technologies are still yet to find commercial success.

Of course there might be fair reason to assume that ship owners, like any businessmen, would be cautious over investing in something new. However, those close to the industry believe that a principle of 'let’s-wait-and-see' is stifling the employment of new technologies.

'The shipping industry is extremely conservative,' Eelco Leemans of the North Sea Foundation (an affiliate of Friends of the Earth International) and once chief officer aboard the Rainbow Warrior II, told me. 'They have this system; it’s a boat, it’s made out of steel, it has a nose and stern, it has got a bridge where people live, it has a big cargo hold and it has a diesel engine; that’s the ship.

'When I ask people in the maritime industry that maybe we have to think about different forms of propulsion like wind. They say:  “Forget about it, we closed that book in the 1920’s, it’s never going to happen again.” So that’s the conservatism, they’re not open to different concepts.'

This aversion to risk means that proper, binding regulations are even more sorely needed. But these are bogged down in the minutiae of international agreements and fears over the consequences of carbon trading or levies.

A global business

At the 59th IMO Marine Environment Protection Committee (MEPC) meeting held in July this year, the last before the UNFCCC Copenhagen climate talks, there was an obvious divide between developed and developing nations over ways to put a price on carbon. The disagreement however was less concerned with the suitability of one mechanism over another, but rather more to do with the implications of what a carbon cost might mean for world trade.

This situation is of course nothing new, but environmental campaigners believe that any fears developing countries might have about a loss of trade resulting from pricing carbon simply don’t add up. They point out that even if a fixed carbon price of $30 per tonne was levied on all shipping emissions, the price of goods carried by sea would only rise by 1 per cent.

Shortly before that final MEPC meeting Peter Lockley, head of transport for WWF-UK said:
'One way out of the current deadlock is for every country to participate in a global shipping scheme, but for the revenues generated by a levy on fuel, or by auctioning emissions permits, to go exclusively towards helping developing countries fight climate change. That way, poorer nations will ultimately receive more than they pay in.

'For such an offer to be credible,' he continued, 'rich countries must show that they are willing to transfer this money and not keep it to plug budget deficits at home. Developed countries have long argued that the emissions belong to no individual country - they can’t now lay claim to the proceeds of any levy on those emissions.'

Track My Ship?

Another option being pursued by the IMO is the CO2 'indexing' of ships - creating a catalogue of individual vessels and their fuel efficiency figures, much as we have for cars. A host of environmental NGOs are backing such a measure on the assumption that having standards in place will lead to improved ship design and operational performance. And, at the beginning of October, the recently formed Carbon War Room, a global initiative founded by Richard Branson amongst others, weighed into this specific issue demanding an accelerated 'global adoption of efficiency standards'.

The need for mandatory measures is of course essential, but perhaps the big question is who will implement such measures? There is a fear amongst industry insiders that fallout from the Copenhagen talks will decide whether it is a global organisation, such as the IMO, that will continue to pave the way for carbon regulations, or whether it will be left to likes of regional bodies such as the EU. A binding, global agreement at Copenhagen would probably see the former. A weak, or non-binding, deal could see the latter scenario arise, whereby ships entering the waters around Europe would have to pay a carbon levy.

Wherever the responsibility finally rests, there is no doubt that actions are needed urgently.
'People can't seem to get their head around the bigger picture,' said Colin Whybrow of Greenwave. 'It is very difficult and it is complicated, but that's not an excuse for doing nothing.

'One of the reasons why we set up as a charity is so that price does not become a barrier to adoption. Usually, as soon as you mention anything environmental the price goes off the screen. What we're trying to do is actually make it pay for itself. If, along the way, ship owners make money out of it, frankly, so what? The bigger picture is the most important thing.'
 
Indeed, environmentalists and regulators alike seem prepared to let the industry in from its cold, dirty past. Jonathon Porritt, founder of Forum for the Future and senior adviser to the Carbon War Room’s ‘battle’ on shipping said at the launch of the scheme:
'The shipping industry has the opportunity to transform its impact on climate change and become the benchmark for environmental efficiency amongst the transport industries. Central to this is utilising tried and tested innovations in conjunction with a willingness to change. Success will be based on widespread collaboration and dialogue throughout the entire industry, working together to achieve a common objective that will provide environmental, social and economic benefits for all.'

The door is open; whether the industry chooses to step through it remains to be seen.

Useful links

To find out more about the Carbon War Room’s battle on shipping
To donate to Greenwave

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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Users Comments

Re: Does shipping have a green future?
Posted By EC008589 1 October 30, 2009 07:05:46 AM

Ultrasonic dibbers permanenty mix oil and water, which engines can burn by simply altering carburettor settings. This would slash oil burnt and pollution made by over 50%.
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