Since the late 1930s, transporting temperature sensitive goods by road and rail depended almost entirely on fossil fuels and high global warming potential (GWP) refrigerants to maintain cargo at the optimum temperature. Today, internal combustion engines have become quieter, more fuel efficient and cleaner. Nevertheless the dependence on fossil fuel and hydrofluorocarbon (HFC) refrigerants remains.
Regulations and social pressure have dramatically changed the way transporters operate in the European Union (EU). Environmental sustainability is a top objective of legislators determined to phase out high GWP refrigerants, control exhaust emissions and limit noise in densely populated areas.
For the past 15 years, the manufacturer of transport temperature control systems, Thermo King, has focused on developing a solution that would meet the future need for an alternative to the fossil fuel or HFC technologies on which the transport industry has depended for so long. In the 1930s, Thermo King pioneered transport temperature control and they have remained the leading innovator in this industry ever since.
HOW THE SYSTEM OPERATES
The company's alternative approach, which remains unique in transport refrigeration today, involves the use of recovered and commercially available liquid carbon dioxide (R744) in an indirect open-cycle system. Unlike other ‘cryogenic' approaches which spray the refrigerant directly into the load space, the Thermo King CryoTech range uses fin-and-tube evaporators as heat exchangers through which the R744 flows, absorbing heat from the load before it is vented to the outside of the vehicle.
The recovered R744 is stored under pressure in a vacuum insulated tank under the chassis of the truck or articulated trailer. It flows to the remote evaporators, one of which is installed in each compartment allowing up to three temperatures on one vehicle. An electronic expansion valve managed by the electric control module regulates the flow of liquid through each evaporator thereby varying their cooling capacity to match the demands of the load and maintain a steady temperature.
Just like conventional HFC refrigerants, the liquid R744 changes state (into a gas) as its pressure drops on leaving the expansion valve and rapidly absorbs heat energy in the process. A regulator keeps gas pressures above the critical 5.5 bar point to avoid the formation of dry ice in the evaporator. After the liquid R744 vaporizes causing the temperature to lower in the insulated box, the vapor is vented outside the box through an exhaust muffler to minimize noise. This is important with regard to the health and safety of operators and goods.
A SYSTEM DEFINED BY WHAT IT LACKS
The system is more notable for what it lacks rather than what it possesses. The truck or trailer unit is cooled with virtually no operating noise without the use of diesel engine, compressor, or HFC refrigerant.
The recovered R744 in the Thermo King CryoTech systems is obtained as a by-product from industrial processes that would otherwise have been released into the atmosphere. As such there are no new carbon dioxide emissions during operation of the CryoTech system.
OPERATING COSTS SIMILAR TO DIESEL
The cost of operating a CryoTech unit over its lifecycle is broadly comparable to that of an equivalent conventional diesel powered unit, although specific applications may favor one or the other. The initial cost of the unit is likely to be slightly higher, due to current low manufacturing volumes. This is offset by its longer service life due to its long life components and fewer "wear" items.
COOLING PERFORMANCE AND NOISE
It has been proven that CryoTech evaporators deliver significantly more cooling capacity than their diesel equivalent at both fresh and frozen box temperatures. Pull down of an empty box can be up to four times faster with R744, making it an excellent choice for distribution operations with a high number of door openings.
With more countries considering the introduction of noise limits on evening and night deliveries - following the example of the PIEK standard in the Netherlands - urban distribution operations wanting to take advantage of low traffic volumes need a vehicle that can perform at 60 dBA or less. All the CryoTech units are PIEK tested and compliant offering sound levels up to 90% lower than a standard diesel unit.
THE ENVIRONMENTAL IMPACT OF THE SYSTEM
But is the CryoTech solution actually more environmentally sustainable?
Engineers at Thermo King performed a detailed carbon footprint calculation on three equivalent systems. The CryoTech (R744) system was first compared to the latest in "conventional" technology (fossil fuel/HFC refrigerant) and to a different "alternative" approach using liquid nitrogen as a refrigerant. The study measures the environmental impact, or "carbon footprint" of each solution.
The comparison took into account significant sources of carbon dioxide emission from cradle to grave, including emissions arising from the energy required to produce the fuels and average annual operating hours. Also taken into consideration were the fuel consumption and exhaust emissions based on independent ATP test data only applicable to diesel units.
As expected, the diesel unit's carbon emissions were largely due to burning of this fossil fuel. Although the nitrogen unit consumes a similar level of fuel to the R744 unit, nitrogen itself requires about three times more energy to produce than the equivalent amount of recovered R744. The total footprint in tons of carbon dioxide over a ten year life was found to be as follows:
• Diesel unit 166 tons
• Nitrogen unit 143 tons
• CryoTech unit 46 tons
The results, while strongly in favor of the R744 solution, were not entirely surprising. CIT Ekologik AB (Engberg et al.) conducted a similar detailed Lifecycle Analysis in 2002 comparing diesel-powered units with CryoTech units. The study showed that the carbon dioxide refrigerator contributes considerably less to the environmental effects than the diesel refrigerator during refrigeration as well as heating.
THE ROAD AHEAD
The study demonstrates that the recovered R744 solution used in the CryoTech range has a carbon footprint approximately 75 percent less than a conventional diesel system and 68 percent less than a nitrogen cryogenic system. But carbon footprint alone will not make a solution commercially viable. The CryoTech range has been shown to also have a similar cost of ownership to an equivalent diesel system while substantially outperforming diesel on both noise and temperature pull down/recovery. These additional features make it ideally suited for urban distribution.
One current limitation is the availability of R744 filling stations. In the early years, there was little to no infrastructure to support the filling of CryoTech units. Since then great strides have already been made in this area.
Existing diesel fuel stations were willing to have R744 storage and dispensing stations installed so the vehicles can be refueled at the same time as the units. By November 2014, more than 47 R744 filling stations were in operation in eight European countries and the number is expected to grow in the coming years.
Thermo King has demonstrated its commitment to this technology, investing heavily in future product research and development, as well as the expansion of the filling station network.
Over the past decades, the science of transport refrigeration has advanced dramatically and the next years will no doubt bring about further innovations. The future promises to be an interesting time, as it is clear that the industry cannot continue to solely depend on traditional fuels and HFC refrigerants. Industry leaders like Thermo King are applying current and emerging technologies to help their customers achieve sustainable and quiet transport refrigeration.
Anthony Bour is product manager oc cryogenics at Thermo King
The Rolex Awards of Enterprise have been a byword for human innovation and the exploration of the unknown for nearly 40 years. Attracting over 30,000 applicants since 1976, the awards recognise and support those who carry out innovative projects that improve lives, protect the planet or expand knowledge.
Announced earlier this year, 2014's Young Laureates are as follows:
• Neeti Kailas (India)
• Olivier Nsengimana (Rwanda)
• Francesco Sauro (Italy)
• Arthur Zang (Cameroon)
• Hosam Zowawi (Saudi Arabia)
With the Young Laureates spearheading projects on a global scale within the sectors of science and health, conservation and exploration to name but a few, the Rolex Awards of Enterprise continue to be a testament to the ongoing endeavour of the human spirit.
14 Nov 2014
Google's self-driving cars have been driving through America for quite a while now. They have driven a combined 400,000 miles in total with the only reported incident relating to a third party's error. Google's driverless cars are electric Prius models and the technology that goes towards making self-driving vehicles possible is pushing the limits on what can be done at a commercial scale. While other manufacturers have already released some enhancements on pre-existing self-driving features, the Google cars are a step beyond this, creating entirely self-driving cars.
With the tests in America proving successful, the driverless vehicle revolution is making its way to Britain. According to an article in the Telegraph, the city of Milton Keynes in Buckinghamshire will be welcoming its first trial of driverless pods in 2015. 20 cars have been ordered and should they prove to be a success, the city hopes to increase this number to 100 by 2017.
At first these pods will be taking passengers from the train station to the city centre. They will initially be limited to 12mph and passengers will be able to check their emails and read the news while being taken to their destination. The pods can be booked via a smartphone app and a trip will cost £2. Instigators of the government scheme are hoping to make £1m in the first year of operation, with some of the main aims being to reduce pollution, congestion and stress.
The Verge reports that more and more car manufacturers are now looking into the possibilities of self-driving cars. While many models were tested on closed tracks at first, open roads are now becoming available for them. Google has managed to secure 25 permits to release driverless cars onto public roads in California. Other manufacturers that have successfully applied for a permit are Audi and Daimler AG-Mercedes Benz. These initial tests are essential for further trails, such as that being performed in Milton Keynes. The successes of these further trails will further highlight the possibilities for future commercial driverless cars.
Milton Keynes will be the first British city to test out the potential of these driverless cars. The manufacturers are hoping that this will significantly lower the number of accidents as over 90 per cent of car accidents are caused by human error. With the success of the google scheme, this bodes well for the future of driverless cars to be used en masse. The future of the driverless car looks very promising and the most recent developments in the car industry could be ground-breaking. The incredibly low accident rate certainly suggests that self-driving cars could be the way forward.
06 Nov 2014
Ah, the ‘paperless office'. Urban myth, or potential reality? We've been talking about the idea of a paperless office for years, but no matter how hard we try, no matter what kind of ultra-cool new tech comes into the market, we're still cutting down trees and using reams and reams of paper every day. It seems that our love affair with paper is almost as strong as our connection to the internal combustion engine, the electric lightbulb and peanut butter - we just cannot do without them in our lives.
However, there is still the potential to go paperless and for certain industries that could be a real advantage. In particular, any industry or profession that could be considered ‘paper heavy' such as accountancy or finance could save a huge amount of money every year by going paperless. Businesses that are trying to emphasise their green credentials could also benefit, improving their reputation as an environmentally aware organisation that is attempting to minimise the use of consumables.
So what could help the transition over to the paperless office easier? Here are five tips that could benefit your organisation in the long term:
1 - Cloud storage vs filing cabinets
One of the constant gripes about online storage is its accessibility. However, the only way you can ‘access' a filing cabinet is to be standing in front of it! With systems such as the Cloud you can get to your files, data and information from anywhere - all you need is a compatible device and a password. The Cloud is one of the biggest steps forward towards the paperless office, and as security issues are tightened and workers have more confidence in the system its benefits are starting to make a real impact on businesses such as international banking, accountancy and finance.
2 - Everyday reports on e-readers
A report doesn't need to be printed out, especially if reports are a regular feature of your business and need to be distributed to multiple recipients. By providing your regular recipients with e-readers, the reports can effectively be sent directly to each reader as a downloadable file, rather than printing out reams of paper. This is beginning to be adopted in multinational organisations with offices around the world, and is a much more efficient way of distributing information quickly onto devices that recipients are accustomed to using.
3 - Mobile technology
The medical profession in particular has adopted the use of mobile technology in an effort to reduce the use of paper. The traditional clipboards at the foot of each patient's bed are now being replaced by tablets used by medical staff that allow them to instantly access a patient's records. One of the biggest advantages of this is that it eliminates the possibility of making mistakes due to being unable to read a note. It's also more efficient at linking multiple departments together to create a more holistic approach to treatment.
4 - Remote working
Faster Internet connections and a computer-literate workforce mean that remote working or ‘telecommuting' is becoming far more common and much more acceptable. It also means a substantial reduction in the amount of paper used within the office environment, as the vast majority of work is done online. Messages are sent electronically (via email, Skype or instant messaging), reports can be sent as attachments and downloaded without the need for printing off copies, and the use of the Cloud (see #1!) means that accessibility is no longer an issue. Remote working is at the vanguard of the paperless office ideal.
5 - Flexible screen technology
Alongside e-readers is another major advance that could change the way we work; flexible screen technology. Innovative R&D companies such as Plastic Logic are at the forefront in developing flexible plastic screens that are quite literally the same width as a sheet of paper, but with the properties of a tablet or laptop screen. While the frame rate and colour palette is not yet quite at the same level as existing technology, it won't be too long before FST or organic electronics make their mark and bring us a step closer to the paperless office.
6 - A change of attitude
But what will really go a long way to spreading the idea and encouraging other industries to go paperless will be a change in attitudes. We're embracing technology such as flexible screens, e-readers and remote systems like the Cloud much more readily, but there's still a way to go before we achieve an office environment where printed reports are a thing of the past. Will we ever be truly ‘paperless', though? That, despite the progress we're making, could still be some way away.
03 Nov 2014
Located on the outskirts of Abu Dhabi is a city that's not simply a new place to live, but a new place to think. A city where you won't smell smoke from nearby factory chimney stacks, you won't see inconceivably high skyscrapers and you won't hear cars honking and passing by at 100mph. What you will find however, is a habitation that works with nature - not against it.
Its name is Masdar City. The metropolis is a flagship for a low carbon and sustainable lifestyle and has aspirations to become the most sustainable city on Earth. Looking down from above, you'll see a cubed shaped city, but down on street level, you'll find narrowly designed paths no longer than 70 metres which are crafted between terracotta walls of traditional Arabic patterns. These streets provide shade and shut out a strong breeze, reducing temperatures by 20°C Celsius from the surrounding desert.
Driverless electric cars hum quietly in a basement level beneath the feet of pedestrians. Without the need for tracks, the cars are guided by GPS and have the route and speed predetermined - the kind of opportunity that is only possible to a city when built from scratch.
Designed primarily by British architects Fosters + Partners and available to be visited by the public as of now, production of Masdar City began in 2006, with the first buildings being completed around 2010. Slowly but surely, the city is expanding and growing to a planned six square miles and is expected to be completed around 2025. The entire project costs approximately US$18bn and the city hopes to eventually house 90,000 people. It will eventually become headquarters for both Siemens and the International Renewable Energy Agency (Irena). Their respective buildings having been completed, but with employees expected to move in either this year or 2015.
The city is powered by 87,777 solar panels, taking up 22 hectares (or 35 football pitches) that was once simply shifting desert sands. The solar plant is the largest in the Middle East, which incidentally produces more energy than Masdar actually needs, sending the excess energy to Abu Dhabi's power grid.
Close by to the solar panels, a prototype nicknamed Beam Down Project exists as the first and only on our planet. Mirrors beam sunlight up to a tower with its own encompassing mirrors, which in turn shoots down the rays that eventually heats up the water that will drive a giant steam turbine.
Impossible to miss inside the city centre is a 45 metre tall wind tower that works as a giant air-conditioning system. A throwback to a traditional Arabic design which was a common sight in every town, the tower sucks air from above using louvers and pushes down a cool breeze throughout the streets of Masdar, while generators simultaneously emit a fine mist.
Leaving the tap running and exiting the house with the light on are things of the past in Masdar, as movement sensors regulate household energy, effectively cutting usage by 51 per cent for electricity and 55 per cent for water. Additional aspects include walls that are designed with cushions of air to limit heat entering or exciting and systems that can recycle 80 per cent of water systems, the remaining being used to irrigate flora amongst the city.
A Turbulent Path
For all its lust and longing to be the poster child of sustainable living spaces, Masdar still has its doubters. Many have taken Masdar's dreams and desires with a pinch of salt, smiling knowingly when completion targets have been moved further and further back, 2015 turning into 2025 and possibly beyond.
An ambitious project is all well and good, but critics request for the real mission to be bringing sustainability to the rest of oil dependent United Arab Emirates and to cities across the entire world to better control climate change. And then there's the fact that the majority of Masdar's residents are the students and staff of the city's own university, named the Masdar Institute, and that the entire population, buildings and developments are but a fraction of what was planned in the early stages, as hundreds more businesses, parks, schools and mosques are still awaiting construction.
However, regardless of not all visions becoming reality, the point remains that Masdar is increasing awareness of sustainability and the means to assist our planet Earth. Companies such as Neuffer are working tirelessly to manufacture a range of windows with state-of-the-art insulation, likewise with Clorox advancing product packaging and chemically reduced cleaning items. If anything, Masdar City has started an awareness shift that could evolve into a transformation that will benefit all our senses for many generations to come.
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