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by ppf 1809 days ago
>"Why bother doing anything here as China is polluting so much? The reality is that we have to eliminate greenhouse gas emissions. All. That includes every tonne we release here, in our home country. No matter what <insert another country> does, we have to stop our pollution here Now."

Exporting your CO2 emissions to other countries (in the form of battery manufacture) does not achieve this goal. If anything, it's worse, because other countries like China will happily burn brown coal to power their factories.

And if it really is so important to stop CO2 emissions, then I'm surprised the author of this article raved about the touchscreens and other electronic gadgets present in all EVs, as they are incredibly resource- and energy- intensive to manufacture (equivalent to the energy needed to drive 1000s of miles), and are not necessary. In fact, I'm surprised the author can tell us that we should enjoy the driving pleasure of EVs, which seems a completely luxurious thing in an article telling us we need to make significant changes to our lifestyle to save the environment.

Also - the author only managed 1000km in one year on an ebike? That's embarassing, and makes it hard to justify the manufacturing expense in energy and materials of the battery and motor. I've had to start driving to work on more days, as I don't have the energy now I have two kids, but I still manage 2,500km of commuting per year on a regular bike (which is older than me), and on a very hilly route.

2 comments

> Exporting your CO2 emissions to other countries (in the form of battery manufacture)

This does not make sense. Battery manufacture is no way equivalent to ICE emissions.

>Battery manufacture is no way equivalent to ICE emissions.

How is it not? It takes a huge amount of energy to manufacture a battery pack (you spend about the first 1/3rd to 1/2 of an EV's life paying off the "CO2 debt"), and it generates all sorts of pollution in the process.

Because they are two completely different things. One is the environmental cost of manufacture, and one is the environmental cost of usage.

Electric and ICE vehicles both have both of these costs. They are all different. If you want to compare things, you need to actually look at all four numbers, not take two unrelated numbers and comparing them for dishonest reasons.

I'm aware of those numbers, and they are still both an environmental cost, regardless of how they happen. EVs swap high environmental running costs for high environmental manufacturing costs, and then we in developed countries externalise those costs by sourcing most of the component parts from other countries, and tell ourselves that we have done something great for the world.

Edit: It takes 25MWh to manufacture just the battery pack for a Tesla, or about 18,000Kg CO2 (assuming a 0.6Kg/kWh CO2 ratio for the Chinese power grid, which is a very optimistic number).

Assuming the power grid where the EV will be used is 100% sustainable (which is very very far from the truth), given that the CO2 output for gas/petrol is 0.3kg / kWh or 2.3kg / liter, and assuming an average of 35 mpg or 7.7 miles per liter, as well as adding a factor of 1.5 to account for refining, storage, and transport losses (which I think is very generous) you would have to drive your new Tesla for around 40,000 miles on 100% renewable power before you've paid off the increased CO2 debt of its manufacture over an ICE. That mileage, by the way, is the number of miles the petrol-engined car would have to drive to produce the 18,000kg CO2 that it took to manufacture the EV battery pack. I am also assuming that the manufacturing cost of the rest of the EV is comparable to an entire ICE car, which I think is fair, as EVs generally contain a lot more electronics (which are very energy-intensive to manufacture), as well as at least one electric motor. An ICE is basically a lump of metal, which has a surprisingly low relative cost of manufacture.

The UK has a relatively "green" power grid, for a developed country, and even here, the difference in CO2 output between the grid and an ICE is so small, you would basically never break even in overall CO2 emissions between an ICE and an EV. For reference, the calculated CO2 output of the UK grid is 0.23kg/kWh.

Also, just for fun, the embodied energy of a 1960's Fiat 500 (assuming its entire 500kg weight is made of steel, which is probably a good enough approximation) is 3MWh, or three laptops.

So what is more sustainable? Claiming that I am making an "dishonest comparison" just ignores the issues with the "green maths" of EVs.

IDK, if your best argument is that an EV breaks even with an ICE at 40,000 miles on the odometer under current conditions that is a very good argument for buying an EV to help the environment! They last a lot longer than 40,000 miles!

Greening up the energy sources for vehicle production should just be next on the agenda!

My "best argument" is that driving less, maybe combined with switching to a more efficient / smaller ICE car, could do as much good as buying an EV. It also avoids all of the new environmental issues caused by the materials required to manufacture an EV, as well as the financial cost.

>Greening up the energy sources for vehicle production should just be next on the agenda!

That would be great, but the article we are discussing has already strongly stated that we need to focus on what we are doing, not on other countries. This is despite the fact that we are effectively mandating the offloading of CO2 emissions to whichever country is manufacturing the major components of our EVs. The battery pack dominates those, in terms of manufacturing energy and resources, however all the fancy electronic toys and touchscreens that all EVs have also have a non-trivial manufacturing cost. My go-to example is that a laptop, comprised of an LCD, a few PCBs and modern microchips, and battery, takes about 1,700 kWh to manufacture. That's enough to drive an EV over 5000 miles. Start adding up all of those screens, CPUs, memory, and other semiconductors present in an EV, and that manufacturing cost starts to look pretty big, too.

Personally, it's clear to me that one of our biggest issues is the embodied energy, and attendant CO2 emissions, of all the consumer electronic goods we are importing at an incredible rate. It's a ludicrous situation when manufacture in Western countries has been tied down by emissions regulations, but there is no control at all on the products we then import.

Those numbers (18,000Kg CO2) do not seem to line up with what is researchers have reported.
I've seen plenty of numbers reported, but I think I made a reasonable estimate. I'd be curious to see what you have found. This paper does seem to indicate that the estimates have come down recently:

https://www.mdpi.com/1996-1073/13/23/6345/pdf

Let's re-do my maths, assuming I over-estimated the CO2 output of manufacturing the EV battery by 100%, and this time we'll assume a charging grid (that is, where the EV will be charged) CO2 output of 0.3kg CO2 / kWh, which is worse than where I live, but better than the US.

I'll also assume an electrical power transmission loss of 10%, and an EV wall-to-wheel efficency of 80%, as well as keeping my well-to-tank CO2 production factor of 1.5 for petrol.

The answer comes out at around 25,000 miles. Better, but not great. At this point, your EV now continues producing CO2 at a rate of 0.12kg/mi, and the ICE car at 0.47kg/mi. By 100,000 miles, your EV has comparatively emitted 21,000kg CO2 (charging emissions of 12,000kg CO2 + battery pack of 9,000kg CO2), to the ICE car's 47,000kg CO2.

I have not taken into account the manufacture and maintentance of all of the EV charging points, which I expect to be substantial.

Looking at the overall - you have about halved your CO2 output for transport, as well as being able to offload about half of that again to whichever country manufactured the battery pack. You have also offloaded all of the point-of-use emissions, again effectively to whichever country manufactured the battery pack. To achieve this great success, an enormous amount of metals and semiconductors had to be used to manufacture all the charging points, as well as the attendant environmental damage and pollution from mineral mining, and disposal.

The fact that the overall benefits of EVs are even debatable, should tell you that this is not the radical change we apparently need to avert a climate catastrophe. To me, it seems like it would provide at best a modest improvement, all while seriously enriching a select few companies and economies.

If it really were about making radical changes to avert a climate catastrophe, it sounds like we should all be cycling, or at worst, using Honda C50 mopeds.

If you say "well, a 50% reduction is worth it", you could achieve that by driving half as much. Or by driving 75% as much, and changing to a car that is 25% more efficient. Or by car-sharing. None of those require enormous amounts of extra mineral extraction and pollution, but none of those make anyone any money, so there we go.

The unsustainable part of personal transport is the huge metal box we all expect to sit in, not the fuel used to power it.

At least you managed to hide your personal dislike to the authors response in your message...
I dislike being told what to do, when their assertions make no sense to my life choices. Especially when most of the arguments boil down to "most of the environmental benefits are not going to happen yet, but soon!".

My personal choices (mostly, keep my house a bit colder, don't buy new electronics, and cycle to work as much as possible) probably do more good, and right now, than buying an EV ever will.

I also don't need to get my thrills out of driving a nice car. If we need to save the planet from CO2-induced death, then that is an absurd luxury that has no place.