http://nordic.businessinsider.com/i-talked-to-finlands-only-self-made-energy-billionaire---and-now-i-realize-how-utterly-futile-electric-vehicles-are-in-addressing-climate-change-2017-2/

Interesting article in the above link which lays out one man's view as to why electric vehicles will not solve the problem of carbon emissions as the increasing demand for jet fuel and plastics means that an increasing amount of crude oil will be extracted and processed and refineries will continue to produce petrol from that crude.

If the petrol is not used for transportation it will just be diverted to some other use, so there is no point in reducing demand for petrol if we don't also reduce demand for all the other products refined from a barrel of crude.

I'm not qualified to dispute the figures and it all appears worryingly logical to me. It seems like if we don't address the world's increasing appetite for air travel and plastics we are all doomed.

His company, St 1, covers about a fifth of the region's petrol retail network.

So no point-of-view issues there, then?

I have very mixed feelings about EVs. They're clearly better in many ways than directly fossil fuelled cars but they're not “the answer” because there isn't a single answer and they still have plenty of problems of their own. We need to be re-engineering society to move away from so much transport in the first place. When that's done EVs would be a less bad solution for some of what's still needed.

I don't think it's anything like as simple as a certain amount of crude oil going in and a fixed amount of each of the products coming out - as I understand it there's a lot of processing going on which can convert one part to another in various ways.

Still, the big thing is that we need to be cutting back on the amount of aviation fuel burned, too.

Pretty much all the existing cars will be run to the end of their natural lives. The question is what is the mix in the next generation.

I care more about the local pollution in our town than I do about climate change

One of these shortens some city-dwellers lives by a few days/weeks/months. The other could well cause complete civilisational collapse, or maybe 'only' worldwide misery, starvation, migration and war. So I'm not convinced about your priorities, but insofar as both these problems tend to have similar solutions, it may not actually matter much.

You are not alone, so I forsee legal action to improve air-quality being a significant driver of decarbonisation activities over the next decade. Fine by me. Sooner the better. I await my 18-yr old diesel being made illegal in more places than just London.

I have asked this question before, but never got a satisfactory answer ('Never answer the question that is asked of you. Answer the question that you wish had been asked of you". Robert McNamara)


So I shall ask again, but in a different way.

As we know the amount of energy that can be had from a chemical reaction via combustion in oxygen, and we use it ever day, do we now the maximum electrical energy we can get out of a non combustion chemical reaction.
Or to put it simply, burn a kilo of gasoline and get about 10 kWh out of it, what is the best that we can get out of a chemical battery, in theory.
Not out of some magical fusion reactor.

Still, the big thing is that we need to be cutting back on the amount of aviation fuel burned, too.


It has got to be taxed on an international basis and soon

If you have't just spend a moment to view

https://youtu.be/DrCX_mawAmk

some people have watched it I believe and AFAIK no-one has claimed it to be untrue.



As a first step I could like to see ALL taxis and mini cabs being EVs.

+!

and most of those electric cars do not need to have sport car performance

or a massive range so many are carting about a load of unwarranted weight quite unnecessarily.

The EV's could be quite a bit cheaper with less weight and less battery.

Car sharing should be encourage and possibly even subsidised so that people needing to do the occasional long journey could leave the EV for someone else to use .

So many cars choking up our roads and only being used for for a few minutes in the day .

mine now I suspect only gets used for 10 or 20 hours in the course of the year .

@ST,

Is this what you are looking for?
https://en.m.wikipedia.org/wiki/Energy_density

Posted By: bxmanStill, the big thing is that we need to be cutting back on the amount of aviation fuel burned, too.

It has got to be taxed on an international basis and soon

Yep

Posted By: bxmanIf you have't just spend a moment to view

https://youtu.be/DrCX_mawAmk

some people have watched it I believe and AFAIK no-one has claimed it to be untrue.

It's actually a bit worse than he claims as he doesn't take into account the extra global-warming effect of emissions in the stratosphere which are something like double (estimates vary quite widely) those of the same amount at ground level.

@ST,

I did think my answer was too easy but had to check:-)

I am sure you know how efficient electric motors are in converting electicity into work, around 80% or so. However, I'm not sure what you mean by theoretical efficiency of a battery. Could you expand?

Mike

I am not anything like expert enough on battery technology to comment further. I am sure there will be further improvements because there is more investment. I am somewhat sceptical about any dramatically new chemistry that will produce a step change. Batteries have been around for a very long time and the need for electrolyte and electrodes will impose physical limits.

What about supercapacitors?
A little way to go yet but densities are going up and costs are falling at decent rates.
And they are supposedly very green to manufacture and easy to recycle.

And as a driving force for technology change electric vehicles surely have to be a better influence than fossil fuel combustion engines?

Posted By: SprocketWhat about supercapacitors?

Space and mass energy densities is not very good, and is unlikely to every be, however they can be charged/discharged VERY fast. So great for recovering energy from breaking etc if there cost come down.

Firstly we have to define what a battery is….

Let’s say it is something that can give electrical power output on demand and be recharged by plugging it into the main. Additionally I will allow it to use the air while charging or discharging, and to have a water tank that needs filling up at the time of charging. It must not give out any gases into the air that are not already there, and must reuse any gases it gives out – so it can give out CO2 while discharging providing it then uses up the CO2 while charging. (Or use 02 while discharging, and release it while charging.)

Given the above, a fuel cell is a battery provided the car has a on-board system to make fuel from mains power!
There is no reason the fuel cannot be as least as energy dance as diesel, we just need the correct catalyst to allow low temperature splitting (and recombining) of CO2 and H20 to make the fuel….

Current batteries have very little of their mass (or size) used to store energy, most of it is used to encase the storage chemicals and to separate cathode from the anode. By using the oxygen in the air batteries can be half in size (google lithium-air battery).

Therefore I expect we can get at least a tenfold improvement on what with have at present just by steady development of what we already have – this is more then we need for cars….

Posted By: ringi

Posted By: SprocketWhat about supercapacitors?

Space and mass energy densities is not very good, and is unlikely to ever be, however they can be charged/discharged VERY fast. So great for recovering energy from breaking etc if there cost come down.

I would not be so sure. Tungsten oxide has demonstrated up to 100Wh/kg already, with graphene not far behind and potentially way cheaper and with plenty of headroom left yet ... ie. around the same storage density as the lower end of the range for Lithium Ion.
And in combination with other power technologies they may open up a whole range of new options.
There are also various battery/capacitor hybrids (ie. not combinations of battery+caps but electrochemical cells with tech adapted from supercapacitors) in development that will offer some advantages of both.

I expect there will be plenty of dramatic changes in battery chemistry in the next couple of decades given all the impetus from new market uses. eg. Not really vehicle based but...
https://www.seas.harvard.edu/news/2017/02/long-lasting-flow-battery-could-run-for-more-than-decade-with-minimum-upkeep

Slight twist of topic: apparently the Daily Mail [¹] claimed that if we went to completely EVs then 20 new nuclear power stations would be required. The usual EV cheerleaders [²] poo-poohed it and it seems the Times has apologized for its version of the story [³]. Somewhere else I saw comment that it was a kW vs kWh mixup - possibly.

One argument made against it was that EVs would take power from the grid off peak so no or little extra generation capacity would be required. This rather misses the point that EVs, while good from the particulate and other local pollution points of view, are likely also to be part of a wider decarbonisation strategy which will including electrifying other things such as space and DHW heating which will also likely be off peak.

My calculation: 25 million EVs, 20'000 km/year·vehicle, 5 km/kWh, 8'000 hours per year = 500 W/vehicle = 12.5 GW total extra average grid generation needed. You can offset a bit of that with less energy use in the processing of crude oil into petrol and transporting it to filling stations, etc, but I suspect that's not going to knock off more than the 0.5 GW on the end.

Anyway, 12.5 GW is not far short of 20 nuclear *reactors* - power stations often have multiple reactors and I think the common boiling water ones are often around 800 MW per reactor with usually two in the power station. See, for example, Hinkley B which has two 660 MWe reactors [⁴].

You can also fiddle around as much as you like with what time you charge cars and with car batteries being used to reduce demand during peaks but still that extra electricity has to be generated somewhere and sometime.

Personally I think that's a good trade off against the problems of internal combustion engines but still we shouldn't kid ourselves that EVs are somehow virtuous: just somewhat less harmful than the alternative.

[¹] https://t.co/42ydpugKsv is said to be a link to the article - nope, not going to click on that myself.

[²] https://twitter.com/bobbyllew/status/831283739946737665 https://twitter.com/QuentinWillson/status/830759292240265216

[³] https://twitter.com/dpeilow/status/831717762259099648

[⁴] https://en.wikipedia.org/wiki/Hinkley_Point_B_Nuclear_Power_Station#Specification

Posted By: ringiEven if we generate 100% of the additional electricity using large diesel generators I believe the EV are a net gain, as the large diesel generators can operate at full load without having to speed up and slow down all the time.

I think I probably agree, mostly. Not least because large diesel generators can likely have better and better maintained emissions controls, be away from spraying their emissions directly in people's faces and there's at least the potential for some carbon capture. But that's not an excuse for saying that EVs won't need any more generation than would otherwise be needed.