Mayor of London, Boris Johnson, with Intelligent Energy's zero emission London black cab.

Eco-engineering in the UK

We take a look at the green technology projects UK engineers are undertaking to prove that going green is good for Britain’s economy as well as it’s environment.

It’s no secret that the UK is lagging behind the rest of Europe in the march to reduce the global carbon footprint. While countries like Sweden provide over 39.8 per cent of its energy through its own renewable energy production - the UK is staggering behind with just 1.3 per cent.

Sweden’s success is largely down to public belief that investment in green technologies not only benefits the environment but is also instrumental for economic growth. And despite our current lack of form in the environmental race, there are a growing number of engineering companies who are doggedly determined to promote that belief in the UK.

Fuel cell taxis

UK clean power company Intelligent Energy specialises in proton exchange membrane fuel cell development. Among several projects currently in the company’s R&D pipeline are fuel cell external chargers for smart phones and fuel-cell motorbikes in partnership with Suzuki.

But the biggest feather in Intelligent Energy’s cap is its zero emission London black cab that will be rolled out during the 2012 Olympics. Key criteria for the zero emission taxi is that it needed to be able to do a full day’s shift on the normal London duty cycle - and operate exactly like a diesel taxi.

“The real changes between a diesel TX4 and ours is that we’ve taken out the engine and the power train and replaced it with a hybrid power train,” explains Ashley Kells, lead technical engineer on the taxi. “It contains a hydrogen fuel cell system and also has a battery. We also have an electric motor that drives the rear wheels and the air con, and the heating also comes partly from the fuel cells.”

As all black cabs are required to have anti-lock brakes the taxi is fitted with a Slip Control Boost System. “This is hardware that equips the disc brakes with anti-lock breaking and regenerative breaking – recovering energy and pumping back into the battery,” says Kells.

Another boon is that the cab has no gears so has seamless acceleration with a top speed of 94mph, and there is no vibration when the taxi is stationery. In fact so normal looking is the cab that Intelligent Energy has also installed a monitor in the seating area to illustrate the ingenious mechanics to passengers.

Building surveying by remote-controlled quad copter

A few years ago chartered building surveyor Andrew Bonnington was called to survey the roof of a nine-storey structure in the centre of a cluster of buildings - that couldn’t be accessed by a hydraulic platform or scaffolding. So he came up with the idea of employing a remote controlled helicopter equipped with an Olympus EP2 10 camera.

Aside from the obvious advantage of accessibility the eco side of using a remote controlled quad is several fold.

“Fully laden the remote controlled helicopter is five kilograms whereas a juggernaut weighs around 10-15 tonnes,” explains Bonnington. “Heavy duty trucks that carry the hydraulic platforms are responsible for about 18 per cent of all vehicle emissions – they use huge amounts of diesel because of the heavy loads they’re carrying and engines have to constantly be running at the base platform. We do have to get our machine from A to B but it does fit in my car very easily.”

The quad copter is powered by a rechargeable battery and can fly and ascend in high wind speeds. Under Air Navigation law the quad copter is classed as a ‘small unmanned surveillance craft’ and as such is restricted to a height of 121.92 metres - which is still at least 50 metres more than some of the highest hydraulic devices.

So why is Bonnington currently the only UK chartered surveyor to utilise such an obvious solution? “I think it’s largely down to money,” he says. “It costs £35,000 – £40,000 to buy one of the quad copters. But it’s actually cheaper to hire than a hydraulics platform or shelling out for scaffolding.”

Recycling nappies

September saw the opening of the UK’s first nappy recycling plant. The site in West Bromwich is the first of five planned over four years by Knowaste, an organisation that specialises in absorbent hygiene product (AHP) waste recycling.

It’s estimated that every year each person in the UK generates 441 kilos of domestic waste and up until September nappies, adult incontinence and feminine hygiene products were the few remaining household products that went straight to landfill or incineration.

Given that the planet is running out of landfill room and that it takes 500 years for your average Pamper to decompose, Knowaste has developed a recycling scheme that can reconstitute AHPs into a variety of products including plastic roofing tiles, absorption materials, recycled paper and green energy.

"This first site represents the beginning of a £25m overall investment in the UK, that will produce capacity for handling about a fifth of the AHP waste stream,” says Roy Brown, ceo of Knowaste. “This equates to a saving of 110,000 tonnes of greenhouse gas emissions a year.”

APHs consist of three components: mixed plastic, wood pulp and super absorbent gel polymers. The Knowaste plant is using its own high-end technology to wash, sterilise and separate the materials to recover plastic and fibre to be used in making new products. To conserve resources throughout the recycling process, water is recaptured from each wash cycle, treated and then reused in the Knowaste system.

Recycling lead acid batteries

Ninety per cent of the world’s lead is used in batteries. In Europe the recycling rate for lead acid batteries is very high but up until recently there was only one recycling plant in the UK. The second, EnviroWales, in Gwent opened in 2007 and currently recycles upwards of 50,000 tonnes of lead acid batteries and scrap metal each year.

David Hardy, operations and technical director of the plant explains the process.

“The scrap batteries are collected in bulk from council depots and Kwik Fit centres throughout the whole of the UK and then they are crushed and separated into three main streams. The plastic casings are cleaned and recycled, the metals inside the batteries are smelted and reused directly as lead and then you treat the lead sulphates.”

Lead sulphates are treated in a chemical process that converts them into a lead carbonate, which is in turn put through a smelt furnace and is converted into metallic lead. Much of the lead metal is then recycled into car batteries – and some goes into building industry in metal sheeting. Interestingly another by-product of the recycling process is sodium sulphate - used in washing powder manufacture.

“In the future hopefully there will be more lead acid battery recycling in the UK,” says Hardy. “Aside from obvious environmental advantages, given that the price of lead has been on an upward trend for several years there’s a fairly good economic incentive too.”

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