THOUGHTS ON ELECTRIC MOTORS IN VEHICLES
Free thinking innovation was the catalyst behind the Connaught V10 and its derivatives. Here Tim Bishop the original engine designer, emissions expert and Chief Engineer at the newly relaunched Connaught Motor Company shares his thoughts on vehicle emissions and power sources.
Background: The Kyoto agreement created a binding set of emission targets that member states have to abide by. The most critical of these was a drastic curtailment in future CO2 emissions. It is important to understand that CO2 is NOT a pollutant in itself. It is a natural product in nature, and nature has many ways of dealing with it to advantage. But it is a measure of energy consumption, and the human race is masterful at wasting energy to a level that nature might not be able to combat. Hence we have” Global Warming” and the only effective stabilising tool we seem to have is to reduce our overall energy consumption by enforcing a CO2 target. It is extremely unfortunate that Gordon Brown chose to label CO2 as a “pollutant” and lump it in with the true nasties such as Hc, Co, and NoX, which are poisonous and combine with sunlight to blow holes in the ozone layer. It is even more unfortunate that he chose to resort to “Technology Forcing” rather than target setting and thus skewed the market towards diesel rather than petrol powered cars despite the known medical issue of diesel particulates. A little knowledge is a VERY bad thing, especially when it comes to legislation. On paper, diesel engines win on fuel economy (CO2) over petrol by about 30% at part load. Sadly, at full load there is almost nothing in it (apart from a large increase in particulates from the diesel). It follows that diesels have to be larger in capacity to produce economical results (and therefore heavier and more expensive to produce). Unfortunately the taxation classes encourage small engines of all types which have to work hard the majority of the time, and this combination explains why we are now suffering poorer air quality and higher airborne NoX emissions than 20 years ago when 92% of motor cars were petrol engined (and, incidentally, 98% clean at the tailpipe for Hc, Co, NoX and particulates).
Past Solutions: In engineering circles the error of the above enforced technological dead-end known as the Diesel engine has been known since before its inception, and engineers around the world were well on the way to producing petrol engines that were as economical as diesel, but with much better emissions longevity, without the problem of harmful particulates and were much lighter and cheaper to make (thus using fewer raw resources). There are many derivative ways to achieve this, and the workings of the Connaught company during the first period laid the foundation for the current up-to-date R+D into future truly ecological methods of motive power.
Today: It now seems that Governmental folly of Technology-Forcing over target-setting has not been recognised, and that an even bigger upheaval and ecological disaster is being enacted by the forced introduction of electric vehicles across the board. Firstly, it is true that, one day, the power density of batteries might approach that of fossil fuels. It is also true that the lithium battery of today has vastly better PD than the lead-acid batteries of yore. But it has to get at least 50 times better to become a rival to oil on Power Density alone, and last five times longer before failing. Lithium resources are small, finite and consume vast quantities of (fossil fuel) energy to mine and process. In short, there will have to be a second revolution in battery technology that does not involve lithium before the ecological argument can match that of fossil fuel. Secondly, there is the issue of efficiency. The attraction of an electric motor lies in its supreme efficiency (in the upper 90%’s) at energy conversion. Compare that with a current value of 35% for a petrol engine and 38% for a diesel engine. Sadly the attraction stops there. Even without the high cost in manufacturing energy of the fuel “tank” (the batteries), the transportation losses of electricity from the power station to the charging point reduce the overall efficiency to perhaps 15%. Couple that with indeterminate control of emissions up the power station chimney (dependent wholly on the choice of the National Grid at the time) and an electric car can easily be twice as dirty as a wholly unregulated car of the 1930’s. The simple difference is that we improve very local conditions at a huge cost to the global environment. The final point is that, if charging electricity were taxed at the same rate as fossil fuel, the electric car would cost two to three times as much to run as a petrol powered car. And even then the cost does not begin to cover the environmental folly. In short, it is no wonder that internal combustion superceded external combustion rather early on in the development of the motor car. Horses for courses.
The Future: Once again dynamic and far-seeing companies must spend their own resources to prepare for the recognition (hopefully not too far away) that this is yet another technological blind alley. One of those companies is Bevan Davidson International who are pursuing ways of pushing vehicular efficiency past 50% in cost-effective ways that can involve both fossil and non-fossil fuels. Formula 1 and very large ships engines are already there, but the former is not cost-effective and the latter a rather difficult package.