The green car market

The Committee on Climate Change said on Monday it expected electric and hybrid vehicles to form up to 40 per cent of cars on the road by 2020.

That\’s an interesting target, isn\’t it? Wonder where they got it from. Is it something that\’s reasonable or likely? Made from whole cloth or thin air?

There are about 1,100 all-electric cars currently on British roads — 0.004 per cent of the total.

Right, but sales are at least soaring are they?

Only 156 electric cars were sold from January to October, compared with 374 for the same period last year.

Ah, no.

They\’re dreaming, aren\’t they?

13 comments on “The green car market

  1. California put legislation in place to demand a certain percentage of non-petrol cars and it seems to be working well, with few complaints from the manufacturers given the reasonable timescale.

    I’m not an expert in this area by any means and targets tend to be aspirational rather than realistic, but cutting down petrol emissions has got to be a good thing in the long run.

  2. As I understand it, the principle push for electric/hybrid cars is for reduction in CO2 emissions.

    However, for electric cars, the electricity must be generated somewhere, stored in suitable form and then used to propel the cars. This process, at least currently, is distinctly energy inefficient; it will always have some inefficiency compared to direct use of the energy source in the vehicle. Thus, the CO2 generated by the original energy source will be multiplied by that inefficiency. This makes it extremely difficult to have a system that reduces CO2 overall, unless the original energy source does not generate CO2 (eg nuclear, hydroelectric – and all those wind/tide things that are vastly expensive). Given this, there is no chance of real CO2 emission reduction until substantially all our other electricity comes from CO2-free sources, because it is easier to generate and use electricity more efficiently for non-mobile purposes than it is with vehicle propulsion, so non-mobile use should come first.

    Concerning the hybrid case, the main benefit is from dynamic braking: that is extracting and storing energy from the motion of the vehicle during braking, so that the energy can be ‘reused’. With an electric motor that can be reverse used as a generator, dynamic braking is made somewhat easier: providing that there are also rechargeable batteries to store the energy (which has an inevitable inefficiency). Another approach uses flywheels, either in conjunction with electric motor/generator or by some ‘purely mechanical’ process of temporary energy storage.

    Overall, the problem (or perhaps non-problem) is that petrol and similar liquid combustibles are one of the better ways (in terms of efficiency, cost and safety) of storing and transferring energy in a way suitable for vehicles, and especially smaller vehicles like private cars. [Aside: direct use of combustibles such as gas, oil and even coal is one of the more efficient and cost-effective ways of providing energy for heating of buildings.]

    [Oh, and Catastrophic Anthropogenic Global Warming (CAGW) through CO2 emissions is, very likely, non-existent: but that is another whole argument.]

    Best regards

  3. It depends on the definition of “hybrid”. All car manufacturers are working on “micro-hybrids” where a small generator and motor are used to assist the engine at very low speeds, but without the giant batteries like the Prius uses. This allows the engine to be turned off when slower than 5mph. In city driving, with all the stop-start driving, this can increase mileage 30% or more

    By 2020, every car on sale will be at least a “micro-hybrid” so the figures are not about what % of cars on sale in 202 will be hybrids, but what the launch dates of the technology are and what the fleet replacement rate is.

  4. “…cutting down petrol emissions has got to be a good thing in the long run…”

    By replacing them with emissions from power stations instead?

  5. “Given this, there is no chance of real CO2 emission reduction until substantially all our other electricity comes from CO2-free sources”

    There are some major savings in the well-to-wheel CO2 emissions from switching to electric. Take a look at the Tesla web site where they show the figures (which uses the current mix of oil/gas/coal/nuclear in the US as the electricity baseline).

  6. @Kay Tie: well, I’ve had a look and it is rather interesting. However …

    I note that all of ‘Tesla’s electricity’ is generated from natural gas, which must affect their CO2 and well-to-station claims. However, if we all switch to electric cars, we are going to need rather a lot more electricity. Whether or not we claim it is generated by natural gas or not, now much of it will not be because of the power stations that exist; in the future, much of it will not be because we need security of supply in the event of gas running out or stopping for some other reason. The UK looks as if it might going to run out of electricity capacity soon (let alone if we add powering our cars), because the government cannot make up its mind whether coal or nuclear is the lesser evil.

    More importantly, I struggle to follow this well-to-wheel stuff. They seem to be imputing some energy value for crude oil, natural gas etc and then claiming that because one needs more processing than the other, there is some efficiency change. If it is a CO2 emissions thingy, why not compute it a grammes/km. The thing that matters to me is the fuel cost per mile travelled.

    Concerning the fuel cost, I calculated from Tesla’s 110Wh/km and my current electricity price of 10.7p/kWh (incl. 5% VAT), and with 95% recharge efficiency for the lithium ion batteries (not quite convinced about the 99.9% at a reasonable charge rate), that the electricity cost would be 1.982 pence per mile. This is actually quite good, though I saw that Tesla were claiming US$0.01 (ie one cent); maybe electricity is much cheaper in the USA (coal, not gas, perhaps).

    As a fair comparison, I used their 51mpg for the petrol-driven Honda Civic. Allowing for petrol at 98p/litre (incl VAT), 50.35 pence fuel tax (excl VAT), and apportioning VAT between the fuel tax and petrol costs, this gives 3.427p/mile fuel costs. [Presumably it is fair to subtract the fuel tax as, with electric cards becoming more popular, other means of taxing for road build/maintenance will have to be found.]

    So on Tesla’s figures, their electric powered car does better on cost/mile by a factor of 1.72, though not by as much as their claimed well-to-wheel factor of 2.19. Over 100,000 miles, this is a saving of £1,445.

    As for the rest: the car seats only two; it has an unspecified price; the range of 244 miles is a bit of an issue, especially as filling up takes hours (presumably one could add more batteries with some loss of storage or elegance, and hard cash); service (yearly or 12,000 miles) is by return to store (I read that as just 4 places in the USA – can anyone else do kinder?). Finally, I prefer to get my facts on technology and society from an independent source and not from product advertising.

    Still, it is food for thought.

    Best regards

  7. There is a CO2 cost to fuel production (e.g. Tar sands). The well-to-wheel figures try to capture that, which is why a simple fuel burned figure isn’t good enough.

    I’m not arguing that Tesla cars can replace our fleet, simply that the calculations are more complex than the “zero emissions” claims for electric cars. Cost wise you’re completely right – leccy cars are largely fuel tax free, which wouldn’t remain so if they were popular.

  8. the government cannot make up its mind whether coal or nuclear is the lesser evil.

    Easy decision – we should build more of both. We are a relatively large country, so diversity of energy supply is essential. Nuclear is low CO2, supports other important activities, and building more nuclear plants on existing sites would have the added benefit of deferring a lot of the decommissioning costs of the old plants. Coal is relatively cheap and abundant in different countries from the large oil and gas producers (and Russia). What is so difficult that the entire government couldn’t make that decision in over 10 years?

  9. It’s bollocks not because of technology – you have too little faith in free markets — but because 2020 is only 11 years time and as cars tend to have a lifespan of about 12 years, so next years sales will still be on the road in 2020. So to get to 40% of vehicles on the road, from zero (or if you count hybrids 1% or so) now will either require 100% of sales to be electric/hybrids in 2020, or very quickly for sales to start to increase.

    On the other hand the way sales are going perhaps the point is there’ll only be 100 cars on the road by 2020, so it’ll only need 40 electric ones…

  10. Nigel: electricity around these parts is about 10 cents per kWh.

    Matthew: quite. I could just about believe 40% of 2020 sales as electric or hybrid cars.

  11. Ed wrote: “[… coal or nuclear …] Easy decision – we should build more of both. We are a relatively large country, so diversity of energy supply is essential.”

    I agree entirely, and am sorry that I did not make that clearer. That does not stop the UK government’s paralysis, rabbit-like in headlights, being the problem. The rabbit should run, in a straight line just about any-which-way; the government should approve powerstations to be built: just about any-which-type and (within broad constraints) just about any-which-where.

    Sam [presumably from the USA] wrote: “electricity around these parts is about 10 cents per kWh.”

    That’s great to hear, both for y’all over the pond, having cheaper electricity than here (really) and for confirming my sceptical view that Tesla had somewhat overstated their case: claimed 1 cent/mile against an actual 1.85 cents/mile.

    However, as I implied earlier, the saving on whole life costs of car ownership and use might not really apply, if car purchase cost differences significantly exceed the fuel saving.

    Though I am willing to concede that, later on, economies of scale of production might well change that balance. This is as and when the costs, volume and weight of rechargeable batteries (and electric engine) ever get to match those of a petrol tank (and petrol engine), and with driving all day for the same (or a tolerable) refuelling delay.

    Whether that will come at 40% of cars by 2020, like Tim, I doubt.

    Best regards

  12. Sorry to nitpick Nigel, I agree with most of what you say. However, it is possible to reduce CO2 emissions by replacing a lot of small IC engines burning fossil fuels at very low efficiencies, with a smaller number of much larger turbines at power stations, converting fossil fuel to electrical power much more efficiently. Obviously some energy is lost in the grid, but not as much as you’d think. I haven’t seen any studies directly comparing CO2 emissions for electric & petrol powered cars, but certainly the potential for savings exists. Also separating the generation of power from the consumption of power allows more flexibility – an existing stock of electric vehicles could take advantage of future advances in power generation efficiency, while with the current fossil-fuel powered cars we can’t really take advantage of technological improvements during the lifetime of the vehicle.
    I don’t see where the breakthrough in battery performance is going to come from to enable all this, but when it does, electric cars seem likely to be better for some applications. No chance of them being 40% of cars by 2020 though.

  13. If you compare parallel hybrids, just see how that daft crate the Prius operates and you will then know why its MPG can be soundly beaten by many traditional vehicles. It has a motor so small that it cannot absorb enough energy in regeneration. A car of that size would need something like 700bhp of brake effort. This is now achievable.

    A series hybrid would come close, for it just has, in effect an on-board generator running at an optimum speed with a buffer of batteries and supercapacitors. Of course, the motoring industry hates series hybrids because all those jobs in gearboxes, engine management, cam profiling, cylinder head design, exhaust system tuning and fuel injectors will be at risk as all we need are steady speed engines. So don’t hold your breath.

    To me the biggest problem with plug-in cars is the time to recharge. To enable a vehicle to have a sensible time to recharge, i.e. 3 minutes, would need something over a 5MWh connection from a charging station to the vehicle (do the math re range and recharge time). That would require a cable thicker than my arm. It can be done or will be done very soon once nanotech gets batteries that can recharge that quickly and robustly.

    In the interim we can work well with series hybrids which can run more efficiently than parallel hybrids or normal vehicles, can have “city” ranges on electric power but 500+ mile ranges using the backup generator. Once we get the recharge infra and battery tech in place those vehicles could be upgraded to work with it.

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