Your browser is no longer supported

For the best possible experience using our website we recommend you upgrade to the newest version of your browser.

Your browser appears to have cookies disabled. For the best experience of Construction News, please enable cookies in your browser.

Welcome to the Construction News site. As we have relaunched, you will have to sign in once now and agree for us to use cookies, so you won't need to log in each time you visit our site.
Learn more

The fuel of the future

CLIMATE CHANGE

In Hornchurch, Essex, BP has embarked on a project that could sew the seeds of a quiet transport revolution, but you may have to wait 20 years to see real progress. Emma Crates talks to Dr Steve Cook

REVOLUTIONS don't always start with a bang.Their beginnings can often be quite modest.

The most radical transport experiment in the UK is being quietly conducted on the A127 near Hornchurch. It involves three DaimlerChrysler buses and a large underground storage tank of liquid hydrogen. It could be the start of a fundamentally different approach to transport in decades to come.

BP, with the help of Bovis Lend Lease and BOC, has built a hydrogen refuelling station next to one of its conventional petrol stations.The station will take part in a demonstration project, due for completion in 2006, which is part of a Europe-wide hydrogen transport programme.

'BP has been involved with hydrogen for about four to five years now.We're now doing demonstration projects all over the world, ' says Steve Cook, BP's hydrogen business development manager.

As an energy carrier rather than a source of power in itself, hydrogen is not strictly classed as a renewable form of energy. But Dr Cook believes it could eventually be a solution to key issues confronting governments globally: climate change, air quality and security of power supply.

'Hydrogen can tackle all three issues.That's why it's an interesting long-term proposition, ' he says.

Hydrogen can be manufactured in a variety of ways, including nuclear power, fossil fuels and solar power.There is some uncertainty as to which pathway will win.

While using renewable energy, such as solar power, to manufacture hydrogen is the best scenario from a climate change perspective, Dr Cook argues that there are still considerable benefits in using natural gas in the medium term.

'Hydrogen fuel cells are much more efficient than an ordinary engine. If you look at the overall picture, we think using hydrogen manufactured from natural gas is still about 30 to 40 per cent better in terms of emissions, ' he says.

But there are technical and economic barriers to overcome, as well as the need to increase public awareness.

Manufactured on a small scale, hydrogen fuel cells are still expensive.They also require costly materials such as platinum, although scientists are working on how to reduce the amounts needed.There are also reliability issues: fuel cells are very intolerant of impurities such as sulphur.

Infrastructure will also present a challenge.While industry already has experience of manufacturing hydrogen on an industrial scale - as a fuel cleaner or as an inert gas in the silicon chip and glass industries - there are distribution issues.

'We understand the technology, but the scale of distribution at a local level is the issue, ' says Dr Cook.

He admits that moving hydrogen around from a central location as a gas would be costly.Ten times as many trucks would be required to transport it as for petrol.

Transporting hydrogen in liquid form would be more economic, but there would be an energy penalty to pay, as it would have to be converted back to a gas again when it reached its destination.

Exactly how hydrogen can be stored on board vehicles is another issue.

'It tends to evaporate, so it's not ideal, ' says Dr Cook.'At the moment lightweight composite high-pressure gas cylinders are the best solution.They can get you to a 200mile range. But people will expect 300-400 miles from a car.'

But while the teething problems are considerable, governments around the world are taking the possibility of hydrogen economy seriously enough to implement a range of research programmes.

'There's certainly a lot of serious money going into hydrogen research but, because uncertainty is high, it's at the appropriate level, ' says Dr Cook.He is reluctant to say how much BP is investing, but the oil giant's main focus of research is currently transport.

'Transport is almost entirely dependent on oil.There is really no other credible alternative than hydrogen. It's a question of when, not if, ' he says.

The challenge is one of demand and supply of this very new technology, a matter of economically sustainable volumes.

'It's a chicken and egg problem.We're working closely with the auto manufacturers to make sure demand and supply grow at the same time, ' says Dr Cook.'It's unrealistic to expect that you'll convert all the petrol stations overnight.There has to be a more phased approach.'

One of the easiest markets for introducing hydrogen is for fleets such as taxis and public transport.

'We would target fleets that have relatively short ranges and come back to the same place every day.Then you only need to build one or two refuelling sites, ' says Dr Cook.'It might be a very good early way of getting vehicles into the market.We're thinking of this in the 10-year timeframe.'

But the time when private cars powered by hydrogen fuel cells could enter the market is anyone's guess.General Motors has said it will start marketing private fuel cell vehicles in 2010.Other manufacturers are less bullish.

'It's very difficult to forecast uptake at this stage, ' says Dr Cook.'We predict a marketing of private hydrogen vehicles starting between 2015 and 2020.There will probably be then a period of five to 10 years of quite slow uptake, and we might see a more rapid market performance after that.'

Projections suggest that by 2030 slightly less than 10 per cent of all vehicles will be hydrogen fuel cell-powered.

'That's fairly optimistic. It's also assuming there won't be any dramatic Government intervention in the meantime, ' says Dr Cook. But he can envisage that in 30 to 40 years there could be enough demand to justify building pipelines for hydrogen.

This, once again, will bring challenges. Because hydrogen reacts with metals, existing pipelines (such as for natural gas) would not be appropriate. Instead polymer materials to line metal pipes, or very specific grades of stainless steel, would be required.

Dr Cook says research is also being carried out on the possibility of adding a percentage of hydrogen into natural gas and transporting it though natural gas pipelines. But it would then need to be separated at point of use.

But he sees a range of applications for hydrogen.Domestic boilers could powered by hydrogen fuel cells within 10 years, and hydrogen power cells for mobile phone and laptop applications could catch on even faster.

'The earliest application will probably be in these micro areas, ' he says.

BP gets CUTE with hydrogen experiment

BP is one of almost 30 partners taking part in the CUTE (Clear Urban Transport Europe) programme, described as the biggest hydrogen demonstration project in world, involving nine European cities with two sister projects in Iceland and Perth.

Dr Cook says BP is involved in projects in Perth, London, Barcelona and Porto and is a minor partner in Hamburg and Stuttgart.

'All the cities have different way of doing things. In London we're delivering liquid hydrogen.

In Barcelona we're partially using solar power to generate hydrogen. In Porto we have a very simple site where we deliver the hydrogen using gaseous trailers, compress it, and store it on site.'

At Hornchurch the BP Bovis Global Alliance (a partnership between the two organisations) worked with technology partner BOC to build a facility to demonstrate underground storage of liquid hydrogen.This is then converted to gas on site.

The design process took over six months to complete.

'Because it was the UK's first public hydrogen facility, the HSE took more of an interest than it probably would have done for other projects, ' says Dr Cook.

'Because it is a gas rather than liquid, the way you manage hydrogen refuelling is different. It has a wider flammability range so we need to be more sensitive, but the end result is just as safe.'

The team designed a double-skinned tank with a capacity of roughly 40,000 litres.

Petrol containers are usually buried in the ground, supported from the side with earthworks, and surrounded with pea shingle. But, because the liquid hydrogen tank needs to be accessed, it sits in a steel cradle inside a reinforced concrete vault.

The civils part of the programme took eight weeks.

'It was quite a conventional project, ' says Tony Maddison, project manager with BP Bovis Global Alliance.'We had a large excavation supported by sheet piling.Most of the vault was covered with reinforced concrete planks.'

The liquid hydrogen is converted to gas and sits in high pressure cylinders at ground level.

'These are contained within the structure, ' says Mr Maddison.

The London project, which will end in 2006, is the only BP site adjacent to a conventional filling station.The other sites in the CUTE project are at bus depots.

'We felt it was important to have at least one site at a public location. It's important to engage in local communities, increase people's awareness and comfort levels, ' says Dr Cook.