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On the road to success...

The automotive industry is one of the biggest and toughest in the world, but David Tonery, the managing director of Oxy-Gen, is determined to prove that a small company based in Dundee can compete with the corporate giants with an invention that could revolutionise engine design – and help to bring about a greener, lower-carbon future...…

On the road to success...

Article by Peter Barr

The Holy Grail of engines has always been the perpetual motion machine, but even though David Tonery has not discovered the secret, he himself never stops moving as he travels the world in his search for a corporate partner to take his young company onto the next stage of growth, in its quest to build a better, “greener” engine for automobiles.
Tonery's interest in making the internal combustion engine more fuel-efficient began at the University of Dundee, where he studied mechanical engineering.  And what inspired his final-year project to develop a more economic engine was buying a 2-litre turbo-charged SAAB which was costing the young Irish student “a fortune” in fuel costs.  With the automotive industry also under pressure to reduce its emissions, it was also a good time to emphasise low-carbon features in engine design. 

After graduating in 2005, Tonery stayed in Dundee and founded Oxy-Gen Combustion, a company whose mission is “to bring about a greener evolution in combustion by delivering low-carbon, lean-burning motor engines.”  Two years later, Tonery won the first of his two SMART awards from Scottish Enterprise to develop his concept, quickly followed by financial help from Michelin Tyre, which has a manufacturing plant in Dundee.  As well as aiming to support small local businesses, Michelin's corporate focus on “sustainable mobility” also fitted well with Tonery's ideas, and this year, the company will showcase Oxy-Gen at a major exhibition in Rio de Janeiro.  In 2008, Oxy-Gen won the Shell Springboard Award for Scotland, in recognition of its efforts to develop low-carbon technology, and also received an Enterprise Fellowship from the Royal Society of Edinburgh  and won the Low Carbon Vehicle Partnership Challenge in 2009.

Interest in Tonery's concept is gathering momentum for a number of very good reasons, and Tonery may have a dual role to play – helping to deliver higher profits at the same time as producing greener vehicles.

The technology

What 29-year-old Tonery is offering the industry is something that researchers have been working on with mixed success since before he was born – a new type of engine which uses a technology called Homogeneous Charge Compression Ignition (HCCI).  An HCCI engine not only reduces emissions of carbon dioxide and consumption of fuel by approximately 15-30 per cent but also improves the overall efficiency of the engine and virtually eliminates emissions of particulates and nitric oxide, and can be incorporated into any type of motor vehicle without the need to modify the vehicle design. 

Several other “green” alternatives are being promoted, including electric cars and hybrid vehicles, but Tonery believes that HCCI will emerge as the dominant engine because all the alternatives have serious drawbacks.  Electric cars, for example, are not only expensive to make but also need a new infrastructure to function, including power points and power management systems to cope with the  drain on the national grid as soon as an electric car is plugged in for charging.  Even  if the infrastructure was in place, electric cars are not low-carbon solutions unless they are able to utilise renewable energy sources.  Using the standard electricity network, the best electric vehicle today produces the equivalent of 99g/km of carbon dioxide – comparable to many conventional passenger cars.  With the huge increase in the number of cars sold in developing countries over the next few decades (see sidebar), the relatively unattractive economics of hybrid or electric cars may hold back sales and persuade more consumers to purchase conventional cars which are “greener” in other respects.  “And the solution,” says Tonery, “is likely to be a fossil- or bio-fuel engine which can burn fuel leaner and reduce emissions without costly after-treatment systems –  for example, HCCI.”

In the longer term, other alternatives may be developed, but in the meantime Tonery sees HCCI as “the stepping stone between present conventional motor engines and the fuel cell, or hydrogen vehicles of the future.”

So what makes Oxy-Gen's new HCCI engine so different?   As Tonery explains, the clue is the company name.  The efficiency of an internal combustion engine depends on the relationship between three different factors: fuel, heat and air.  While other developers focus on new types of fuels (including biofuels) and heat (for example, re-circulating exhaust gas), Oxy-Gen focuses on the “air” aspect of the equation.  

One of the problems in previous HCCI designs is that once you get rid of the spark plug, you need perfect conditions for “spontaneous combustion” – balancing air pressure, temperature and air-to-fuel mix.  Some critics also point out that HCCI operates best when the engine is running at medium speeds, below 55mph.  At low speeds or “light load,” HCCI can lead to problems such as misfiring or partial combustion, while at high speeds or “high load,” ignition tends to run away and lead to “engine knock” which not only harms performance but also damages the engine. 

Tonery's breakthrough was to increase the oxygen used by the engine.  Based on the fact that air is roughly 21 per cent oxygen (which burns well) and about 78 per cent nitrogen (which won't burn), he realised the simple solution was to enrich the oxygen content.  “Altering the composition of the air was one more tool to use to improve HCCI,” says Tonery. “It is more volatile but also increases the ignition, and gives us more control, efficiency and flexibility.”  According to Tonery, Oxy-Gen's current technology can handle the engine load “90 per cent of the time,” and the target is to further improve that to full load.   Oxy-Gen already has two patents for its engine technology, and after the company signs an agreement with an industry partner, this could lead to a flood of new patents as the engine moves into production.  Within two or three years, says Tonery, other manufacturers will try to catch up, but for the moment he has “an idea that works” and is confident he is a few steps ahead of his rivals.


Future plans

Tonery may not be re-inventing the wheel, but with a little help from Michelin and others, (including Zeochem – a world leader in air separation systemswhose technology was used on the NASA Space Shuttles), the next step is for Tonery to build a team of 6-8 people to develop the concept, perform benchtop testing and finally “integrate all the components and get into production.”  Within two years, says Tonery, the company will have a production-ready demonstrator engine.  Stationary versions of the engine (e.g. generators) could be rolling out in three years, followed by marine versions.  HCCI automobile engines could follow in five years. 

A recent survey by NAIGT (the New Automotive Innovation and Growth Team), which polled the major players in the automotive industry, found that most companies agree HCCI will not be widely available until 2020 at the earliest, mainly due to problems with auto ignition.  Although this may appear to be discouraging, for Tonery it means an opportunity, because it buys him time to perfect his invention and prove it is a practical alternative which offers major benefits compared to other HCCI engines, thanks to its unique approach to how the engine uses oxygen. 

According to Tonery, the industry cannot be sure yet exactly how much HCCI will deliver in terms of fuel savings.  Some manufacturers mention a figure of 15 per cent, while others go as far as 30 per cent.  Tonery may play it safe for the moment, saying the reality is likely to be somewhere in between, but he is quietly confident that 30 per cent will be possible within the next few years – especially if Oxy-Gen's technology becomes widely adopted.  Some manufacturers including Honda have already said that only one engine will win the technological race, with HCCI the favourite. 

There have been many false starts in the history of engines, including perpetual motion machines and cars that run on water, but Tonery is driven to succeed with his version of HCCI.  He believes the secret of success in the automotive industry is to understand what manufacturers want, and he is sure HCCI will prevail because it offers multiple advantages.

In  Scotland, we have had James Watt and Robert Stirling, the inventor of the “heat economiser” Stirling Engine.   Will David Tonery and Oxy-Gen be next?  “Asking too many questions can kill innovation,” says Tonery, but his new design for HCCI may be the answer.  








"On the road to success...". Science Scotland (Issue Nine)
Printed from on 03/07/20 11:41:30 PM

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