Lotus Exige Tri-fuel

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The supercharged Exige 270E Tri-fuel is part of Lotus’ research to understand the complex combustion process involved in running on mixtures of alcohol fuels and gasoline, which will be important for a successful transition from today’s fuels to the sustainable, synthetic fuels of the future. The research into sustainable alcohols is progressing at Lotus’ Hethel headquarters in Norfolk, UK and involves input from the Royal Society of Chemistry’s Alternative Fuel Symposium Series, the Low Carbon Vehicles Innovation Platform, developed by the Technology Strategy Board and direct discussions with the University of Sheffield.

This prototype Lotus is capable of switching from gasoline to bioethanol to methanol (CH3OH), which can be produced synthetically from CO2 and hydrogen. Ultimately, emerging processes to recover atmospheric CO2 will provide the required carbon that can entirely balance the CO2 emissions at the tailpipe that result from the internal combustion of synthetic methanol.

Lotus Engineering regards sustainable alcohols as the third step in a process towards carbon neutral driving:

1st Generation: there is a handful of current bio-ethanol cars on sale around the world. These cars run on E85 bio-ethanol, which is produced from valuable arable crops (food). This is unsustainable in the short and medium term as global demand for fuel will outstrip the supply available from farmland to the detriment of food production.

2nd Generation: the next generation bio-ethanol fuels will be based on biomass waste, for example crop stubble, waste vegetable-based oils and any biodegradable waste matter. This is thought also to be unsustainable in the medium to long term as the required volume of biomass increases beyond that which can be supplied.

3rd Generation: sustainable alcohols such as synthetic methanol that can be produced from entirely sustainable, readily available inputs, with an environmentally neutral overall impact.

4th Generation: Direct Methanol Fuel Cells: over the longer term, sustainable alcohols in internal combustion will facilitate the soft introduction of direct methanol fuel cells as a long term sustainable future fuel.

The Brighton to London jaunt in the Exige illustrates how easy it is for synthetic methanol to be embraced over time as a future fuel for road transport.

Methanol (CH3OH) can be produced synthetically from CO2 and hydrogen. Ultimately, emerging processes to recover atmospheric CO2 will provide the required carbon that can entirely balance the CO2 emissions at the tailpipe that result from the internal combustion of synthetic methanol. The result is that a car running on synthetic methanol, such as the Exige 270E Tri-fuel would be environmentally neutral.

As well as being green, the great benefit of synthetic methanol is that it would use similar engines and fuel systems to those in current cars; and synthetic methanol can be stored, transported and retailed in much the same way as today’s liquid fuels such as petrol, gasoline and diesel.

Synthetic methanol also possesses properties better suited to internal combustion than today’s liquid fuels, giving improved performance and thermal efficiencies. And it is ideal for pressure-charging turbo’s and superchargers already being introduced by manufacturers to downsize engines in a bid to reduce emissions and vehicle weight.

Mike Kimberley, Chief Executive Officer of Group Lotus plc, explains: “Lotus is a world-class leader in research into a variety of alternative fuels; each has its merits and challenges and some options could be more easily implemented than others. But while motorists want to be green, we do not want to change culture or their habits, with reluctance to spend more at the pump, or sacrificing the performance of their car.

The Lotus Exige has similar performance levels to the electric Tesla Roadster, begging the question: will there still be a demand for combustion engines in 20 years time?

Geraint Castleton-White, Head of Powertrain at Lotus Engineering explains:
“For car companies and the motorist, the use of sustainable alcohols like synthetic methanol requires relatively few changes to the vehicle. It can also use the current fuel distribution infrastructure, which is a huge advantage for suppliers.

This research is just one aspect of Lotus Engineering’s ground-breaking work on environmentally-friendly vehicles. It is involved with a number of electric vehicle projects, has successfully integrated hybrid technologies into vehicles such as its EVE demonstrator, and recently announced results on a collaboration with Continental Division Powertrain on the Low CO2 downsized three cylinder engine.

David Bott, Director of Innovation Platforms within the Technology Strategy Board in the UK says: “The approach taken by Lotus Engineering is a good balance between the desire for the lowest carbon emissions and the practicality of car evolution. The drive for low carbon transport is a real
imperative and its progress will require short, medium and long term solutions.”

“At present, the motor industry is seeking a route to reduce CO2 emissions just at the tailpipe; this focus is far too narrow. Sustainable alcohols such as synthetic methanol have the potential to reduce the overall CO2 footprint of internal combustion vehicles to zero. As it could be produced through CO2 recovered from the atmosphere and given a tax incentive, it immediately becomes a green, cheap and more desirable fuel. For those compelling reasons motorists, legislators and car manufacturers must switch to a sustainable alcohol like synthetic methanol.”

Tony Ryan, ICI Professor of Physical Chemistry at the Department of Chemistry at The University of Sheffield says: “There is a great opportunity to develop methanol as a transport fuel in a mixed energy economy that embraces a wide range of primary energy sources, including nuclear, solar, and other renewable power sources. Combining atmospheric CO2 with hydrogen to form methanol provides a pathway to personal transport with low carbon emissions that uses the existing liquid-fuel infrastructure and Lotus Engineering offers world leadership in the development of engines to use
these fuels of the future.”