Lotus Exige 270E Tri-Fuel
Lotus Engineering has unveiled its latest development towards carbon neutral road transport. The Lotus Exige 270E Tri-fuel is the most powerful road version yet of the Exige (0-60mph/96kph in 3.88 seconds, a top speed of 158mph/255kph, 270hp with 201kW and 273PS at 8000 rpm) and it runs on any mixture of gasoline, bio-ethanol and methanol. Emerging technologies will allow alcohol fuels such as methanol, already a proven internal combustion fuel, to be made synthetically from CO2 extracted from the atmosphere.
An alcohol-based fuel derived renewably from atmospheric CO2 would allow society to transfer relatively easily to sustainable, renewable, carbon-neutral internal combustion. Lotus Engineering is researching the use of sustainable synthetic alcohols as potential future fuels, possibly for introduction within 15-20 years. The 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.
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. 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.
An alcohol-based fuel derived renewably from atmospheric CO2 would allow society to transfer relatively easily to sustainable, renewable, carbon-neutral internal combustion. Lotus Engineering is researching the use of sustainable synthetic alcohols as potential future fuels, possibly for introduction within 15-20 years. The 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.
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. 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.
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.
Lotus Engineering’s Lotus Exige 270E Tri-fuel technology demonstrator illustrates how easy it is for synthetic methanol to be embraced over time as a future fuel for road transport. The Exige 270E Tri-fuel, with its supercharged 2ZZ-GE VVTL-I engine, could be the forefather of a new generation of conventionally driven cars that have the potential to 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.
Lotus Engineering’s Lotus Exige 270E Tri-fuel technology demonstrator illustrates how easy it is for synthetic methanol to be embraced over time as a future fuel for road transport. The Exige 270E Tri-fuel, with its supercharged 2ZZ-GE VVTL-I engine, could be the forefather of a new generation of conventionally driven cars that have the potential to be environmentally-neutral.
Synthetic methanol’s green credentials arise from its potential to be CO2 completely neutral. The most likely future mass-production of the fuel is by using electrochemical techniques to combine oxygen, hydrogen and carbon:
• Carbon could be sourced from carbon dioxide recovered from the atmosphere using either large scale extraction facilities or biomass.
• Oxygen would be taken from the atmosphere
• Hydrogen would be acquired through the electrolysis of water; challenges remain in the electrical power required; in a green future, this could be supplied from renewable sources, an issue already being addressed by supporters of hydrogen as a fuel
Techniques for the production of synthetic methanol are well developed and understood, although not yet at an industrial scale. An early solution would be the co-location of a nuclear or hydroelectric powerplant with a conventional power station – the hydrogen generated by hydrolysis of water would be combined with CO2 from either fossil or biomass sources to make liquid methanol. In the future, large volumes of CO2 could be extracted from the atmosphere.
As well as being green, another crucial advantage of synthetic methanol is that it can be introduced relatively simply. As the Exige 270E Tri-Fuel demonstrates, only small changes to engines are required, such as:
• Sensors to detect alcohol content
• Slightly modified software for engine management controls/ECU’s over ethanol/gasoline and flex fuel
• Fuel lines compatible with alcohol
• Higher flow rate fuel pump and injectors
• Fuel tank material, compatible with alcohol
In addition, as a liquid, synthetic methanol can be transported, stored and sold to motorists exactly as today’s liquid fuels are, with only minor modifications.
Synthetic methanol is better suited to spark-ignition combustion than today’s liquid fuels, delivering better performance and thermal efficiencies, due to its higher octane rating and better resistance to ‘knock’. As a result, it is a fuel that will benefit the motorists in terms of driving experience. For example, the Exige 270E Tri-fuel is quicker to 60mph from standstill and has a higher top speed when using 100% synthetic methanol fuel than with conventional petrol/gasoline. Synthetic methanol is also ideally suited to pressure-charging, a trend already well underway as car makers look to downsize engines to cut emissions.
• Carbon could be sourced from carbon dioxide recovered from the atmosphere using either large scale extraction facilities or biomass.
• Oxygen would be taken from the atmosphere
• Hydrogen would be acquired through the electrolysis of water; challenges remain in the electrical power required; in a green future, this could be supplied from renewable sources, an issue already being addressed by supporters of hydrogen as a fuel
Techniques for the production of synthetic methanol are well developed and understood, although not yet at an industrial scale. An early solution would be the co-location of a nuclear or hydroelectric powerplant with a conventional power station – the hydrogen generated by hydrolysis of water would be combined with CO2 from either fossil or biomass sources to make liquid methanol. In the future, large volumes of CO2 could be extracted from the atmosphere.
As well as being green, another crucial advantage of synthetic methanol is that it can be introduced relatively simply. As the Exige 270E Tri-Fuel demonstrates, only small changes to engines are required, such as:
• Sensors to detect alcohol content
• Slightly modified software for engine management controls/ECU’s over ethanol/gasoline and flex fuel
• Fuel lines compatible with alcohol
• Higher flow rate fuel pump and injectors
• Fuel tank material, compatible with alcohol
In addition, as a liquid, synthetic methanol can be transported, stored and sold to motorists exactly as today’s liquid fuels are, with only minor modifications.
Synthetic methanol is better suited to spark-ignition combustion than today’s liquid fuels, delivering better performance and thermal efficiencies, due to its higher octane rating and better resistance to ‘knock’. As a result, it is a fuel that will benefit the motorists in terms of driving experience. For example, the Exige 270E Tri-fuel is quicker to 60mph from standstill and has a higher top speed when using 100% synthetic methanol fuel than with conventional petrol/gasoline. Synthetic methanol is also ideally suited to pressure-charging, a trend already well underway as car makers look to downsize engines to cut emissions.
The Lotus philosophy is all about performance through light weight. The Exige 270E Tri-fuel is built to the lightest specification possible without resorting to expensive and rare materials. The performance improvements of using synthetic alcohol have been made through increasing the power of the engine without increasing the weight of the engine and therefore the overall weight of the car.
The Engine
The heart of the Exige 270E Tri-fuel is a Roots-type supercharger (with a sealed-for-life internal mechanism meaning that it does not require the use of the engine’s oil) and air to air intercooler attached to the tried and tested 4-cylinder, 1.8 litre 2ZZ-GE VVTL-i engine. Using a development of the supercharger and intercooler package from the Exige S, the Exige 270E has peak power of 270 hp (201 kW, 273 PS) at 8000 rpm, 184 lbft (260 Nm) of torque (at 5500 rpm) up by 51 hp (38 kW, 52 PS) or 19% and 25 lbft (45 Nm) or 21% over the standard gasoline Exige S. Maximum engine speed is 8000 rpm (8500 rpm transient for up to 2 seconds).
The low carbon number alcohol fuels methanol and ethanol give more power when burned in the engine than conventional gasoline (petrol) fuel. The performance benefits come largely from the high heats of vaporization of methanol and ethanol, which give strong charge-cooling effects, and the increased octane ratings. There are other secondary thermodynamic effects. Methanol's higher heat of vaporization leads to a slightly higher performance relative to ethanol. The roof scoop ensures that the air-to-air intercooler works as efficiently and effectively as possible in all climates and environments. All charge air ducting has been kept as short as possible with large diameter pipes making sure that the bends in these ducts are not too tight, to the benefit of throttle response and efficiency. The Roots-type Eaton M62 supercharger is run from the crankshaft, and has an integral bypass valve for part load operation.
The 2ZZ VVTL-i engine has two cam profiles – a high speed cam and a low speed cam. The seamless switch point between these two cams is completely variable depending upon driving conditions and engine load. This gives the Lotus Exige 270E Tri-fuel a smooth and linear surge of power from idle speeds all the way to the maximum 8500 rpm. An electronic drive-by-wire throttle ensures the quickest engine response possible whilst keeping the emissions as clean and as low as possible, to meet relevant legislative demands. Six fuel injectors have been fitted to increase fuel flow to the engine at normal and higher engine speeds and loads.
The Engine
The heart of the Exige 270E Tri-fuel is a Roots-type supercharger (with a sealed-for-life internal mechanism meaning that it does not require the use of the engine’s oil) and air to air intercooler attached to the tried and tested 4-cylinder, 1.8 litre 2ZZ-GE VVTL-i engine. Using a development of the supercharger and intercooler package from the Exige S, the Exige 270E has peak power of 270 hp (201 kW, 273 PS) at 8000 rpm, 184 lbft (260 Nm) of torque (at 5500 rpm) up by 51 hp (38 kW, 52 PS) or 19% and 25 lbft (45 Nm) or 21% over the standard gasoline Exige S. Maximum engine speed is 8000 rpm (8500 rpm transient for up to 2 seconds).
The low carbon number alcohol fuels methanol and ethanol give more power when burned in the engine than conventional gasoline (petrol) fuel. The performance benefits come largely from the high heats of vaporization of methanol and ethanol, which give strong charge-cooling effects, and the increased octane ratings. There are other secondary thermodynamic effects. Methanol's higher heat of vaporization leads to a slightly higher performance relative to ethanol. The roof scoop ensures that the air-to-air intercooler works as efficiently and effectively as possible in all climates and environments. All charge air ducting has been kept as short as possible with large diameter pipes making sure that the bends in these ducts are not too tight, to the benefit of throttle response and efficiency. The Roots-type Eaton M62 supercharger is run from the crankshaft, and has an integral bypass valve for part load operation.
The 2ZZ VVTL-i engine has two cam profiles – a high speed cam and a low speed cam. The seamless switch point between these two cams is completely variable depending upon driving conditions and engine load. This gives the Lotus Exige 270E Tri-fuel a smooth and linear surge of power from idle speeds all the way to the maximum 8500 rpm. An electronic drive-by-wire throttle ensures the quickest engine response possible whilst keeping the emissions as clean and as low as possible, to meet relevant legislative demands. Six fuel injectors have been fitted to increase fuel flow to the engine at normal and higher engine speeds and loads.
Lotus Engineering regards sustainable alcohols as the third step in a process towards carbon neutral driving. The current E85 (85% ethanol and 15% petrol/gasoline) based movement represents the first stage in building momentum towards sustainable fuels. The valuable learning from the current bio-ethanol vehicles on the market means that synthetic methanol would be managed technically and within the existing transport, storage and distribution infrastructure.
1st Generation: there is a handful of current bio-ethanol models 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.
Lotus Engineering believes governments, fuel suppliers and car manufacturers have a key role to play in the adoption of sustainable alcohols as a future green fuel.
If car manufacturers were incentivised to produce next generation models for introduction over the next 5 to 10 years as flex-fuel, running on any mix of petrol/gasoline, bio-ethanol or synthetic methanol, there would be no need for an unfeasible instant global changeover. Fortunately, E85 bio-ethanol and subsequently synthetic methanol can be introduced gradually to the marketplace.
Should fuel suppliers increase the industrial-scale production of synthetic methanol, it could be introduced to forecourts across the globe within 15-20 years and become a global standard within a further 10 years.
1st Generation: there is a handful of current bio-ethanol models 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.
Lotus Engineering believes governments, fuel suppliers and car manufacturers have a key role to play in the adoption of sustainable alcohols as a future green fuel.
If car manufacturers were incentivised to produce next generation models for introduction over the next 5 to 10 years as flex-fuel, running on any mix of petrol/gasoline, bio-ethanol or synthetic methanol, there would be no need for an unfeasible instant global changeover. Fortunately, E85 bio-ethanol and subsequently synthetic methanol can be introduced gradually to the marketplace.
Should fuel suppliers increase the industrial-scale production of synthetic methanol, it could be introduced to forecourts across the globe within 15-20 years and become a global standard within a further 10 years.