Being a fan of all things Lotus, I’ve been following news about their tri-fuel Exige 270E technology demo with some interest. It’s essentially a standard Exige that has been modified to run on either Petrol, Ethanol or Methanol – or any combination of the three. Sensors tell the ECU what fuel is being used and it then adjusts the engines combustion appropriately.
Although there has been a lot of focus on hydrogen as a fuel for the future, Lotus is arguing that due to the inherent problems and costs involved with hydrogen, synthetic methanol may be a better choice. From my layman’s perspective Lotus arguments seem pretty sensible.
Simply storing hydrogen is difficult, you can either compress it to 700psi, or liquefy it at -230 degrees centigrade, neither of which are best suited for transport in vehicles. It’s also not very energy dense, I understand it’s something like a fifth the density of petrol, and once you add in the energy spent creating and storing if the well-to-wheel efficiency drops even further.
One of the biggest problems though is that hydrogen will mean a complete change in engine design and use, a hard change that will cost manufactures and support services like petrol stations huge amounts to implement.
Methanol, whilst not a panacea, does offer some advantages. It’s a liquid at room temperature for a start. It’s also more energy dense than hydrogen, though not as dense as petrol. It does however have a higher octane rating – something that allow the 270E to produce more power than the regular petrol based version.
In my view though the biggest advantage has to be that a move over to methanol can be gradual. The chaps from Lotus reckon most modern engines should be able to run methanol with very few changes. The main physical obstacles seem to be around the fact that methanol is more corrosive so seals, pipes, tanks etc need to be changed.
That being the case, a change over to methanol would be much simpler for manufacturers. Potentially they can future proof their cars against future ethanol or methanol fuels now, or at least within a few years.
If new cars were able to use these fuels in various mixes, fuel producers would be able to add synthetic methanol into their fuels and phase out petrol over a period of time.
Of course, methanol still produces CO2, but as it can be synthetically produced from carbon dioxide and hydrogen the potential exists to recover these from the atmosphere or existing industrial waste collection. The idea being that CO2 emissions at the exhaust will be balanced to a neutral point.
It seems like an interesting technology challenge, and I’m glad to see Lotus taking a lead in it. What I’d love to see though is Lotus taking a lead in delivering tri-fuel cars to customers. It would seem like most of the development for their current Elise and Exige range has been done for this project. If the costs per car weren’t too great it would be a hell of a marketing tool, and would certainly set them apart from their competitors. Would the other manufacturers follow? Who knows, but it’s a Toyota unit that Lotus have been working with, so it would be easy for at least one major company to follow.
