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While electric buses are almost certainly an emissions win compared to the no doubt primitive and dirty Chinese diesel buses, I doubt it is it fair to call them zero-emission? China burns a lot of coal for electrical power.



That is picking nits :-) Not only is China rapidly building nuclear power plants, containing the emissions of one plant burning coal is easier than containing the emissions of the 10,000 buses that plant provides power to operate.

There is also a benefit to China converting from oil (something imported[1]) to coal (something available locally[2]).

[1] https://oilprice.com/Energy/Crude-Oil/Chinas-Becomes-Worlds-...

[2] https://en.wikipedia.org/wiki/Coal_in_China


> That is picking nits

No, actually it's not. The source of electricity matters, and just because something doesn't directly emit pollutants does not mean its power is derived without emitting pollutants.


I don't disagree the source of electricity does matter. But who is to say where the electron coming out of the plug came from? Perhaps it came from one of their existing nuclear plants[1] ?

For me, when you get to the point where you can construct two valid statements that both are supported by available information, yet one disproves a statement and the other proves it, you have reached the point of 'nits'.

In this case :

"They are not zero emission because electricity can come from a coal fired plant."

"The are zero emission because electricity can come from a nuclear power plant."

Pedants could go a different way, they could say "the bus is zero emission but the infrastructure isn't."

We saw a lot of that with solar panels where people would argue that the energy to smelt the aluminum to make the frames and furnaces to grow the silicon ingots far exceeded any amount of energy that the solar cells themselves would provide.

But one has to wonder, what is the point of arguing at that level when, as the article states, the pollution where the buses are deployed is significantly less?

[1] https://en.wikipedia.org/wiki/Nuclear_power_in_China


> But one has to wonder, what is the point of arguing at that level when, as the article states, the pollution where the buses are deployed is significantly less?

Pollution where deployed isn't the issue, overall pollution is (the main impact of CO2 is climate change on a global scale). Significant reductions in pollution are to be celebrated, but it's wrong - and takes away from your point - to emphasise something as "zero emission" when it isn't.


Pollution where deployed isn't the issue, overall pollution is

I think inhabitants of large Chinese cities that have to wear masks when they go for a walk would disagree.

Actually, both things are quite relevant. Pollution in cities poisons and kills people in the short run, climate change would kill us all in the long run.


It’s a toxic argument, because in practice it’s used to absolve diesel or gas cars entirely. It‘s also a way of missing the forest for the trees. Gas cars can never be clean, electric cars are in fact cleaner from the get go and have the potential to be (nearly) entirely clean. Building a world where that is possible requires a large investment in infrastructure and that will only happen if there is a large scale switchover to electric cars.

You are certainly not wrong when you say that also electric cars pollute, but you should be aware of how and when and why this kind of argument is usually deployed.


You can't say they're cleaner from the get go. They could rely on such a different set of polutant products that you can't compare them in general. Also building one electric car when the production chain doesn't exist is obviously going to pollute much more than one has vehicle with its existing infrastructure. It's because we consider the industrial evolution and the usage lifetime that we can compare the two and EVs might be considered less pollutant (even though once again you're comparing very different kinds of pollution). It's not because they seem much better in theory that you should give the EV industry any favorable bias—they need to be held accountable even more than the existing industry because they will probably shape the future of the automotive industry.


A thing that is pointed out is the life of a vehicle, especially a bus might be 15-30 years. During that time the grid will become a lot cleaner. Where with a diesel bus emissions wise you're all in.

There is also the long tailpipe, diesel buses produce toxic emissions where people are, coal fired power plants produce emissions elsewhere. (not necessarily, but likely)


Yes you are nitpicking. It's like if someone says "paper bags reduce wastes by 50%" and you retort "welllll you still need need factories to make those paper bags." It's literally the definition of nitpicking

In this case, you're doing so in an attempt to undermine the activity raised in the parent. Not sure what your intention is, but definitely not supported by logic


I think actual nitpicking would be "welllll paper bags reduce plastic waste by X %, but they also increase paper waste by Y %".


I flew across China last month ... Lots of open cast coal mines, each with a power station next to it .... But they're planning ahead, those power stations are surrounded by thousands of windmills, more than I could count leveraging the power distribution network


how do you contain CO2? its a gas so very voluminous, do you propose liquefying it and keep it refrigerated?



Not yet proven at commercial scale, and likely to be expensive:

"Although the processes involved in CCS have been demonstrated in other industrial applications, no commercial scale projects which integrate these processes exist; the costs therefore are somewhat uncertain. Some recent credible estimates indicate that the cost of capturing and storing carbon dioxide is US$60 per ton,[173] corresponding to an increase in electricity prices of about US 6c per kWh (based on typical coal-fired power plant emissions of 0.97 kg (2.13 lb) CO2 per kWh). This would double the typical US industrial electricity price (now at around 6c per kWh) and increase the typical retail residential electricity price by about 50% (assuming 100% of power is from coal, which may not necessarily be the case, as this varies from state to state)."


Actually increasing my residential rate by 50% to get zero CO2 emissions at the plant sounds like a great deal to me. I would have expected the price to be even higher.


CO2 has numerous industrial applications, so you typically don’t store it but bottle it and send it elsewhere. Beer manufacturing (to add bubbles) is an anecdotic use; green house or urban farm agriculture is a growing need.


the need for CO2 is extremely low, why is carbonating drinks even referenced whenever carbon capture is mentioned?

the amount of CO2 absorbed in the drink will be released upon opening the drink, or else burping or farting.

the amount of CO2 the plants in a green house absorbs is offset by atmospheric CO2 not absorbed by the plant...

yes CO2 has niche uses, but whenever I see people mention CO2 utilization in the context of emissions reduction, it instantly unmasks their lack of knowledge.

The idea that we simply capture it at the chimney, and then bring it to where we need it is in fact very similar to the thought process in a perpetuum mobile.

consider pure graphite as a model of coal, you can burn it, which binds 2 oxygens for each carbon atom, now we capture the CO2, strip the oxygens, and cram all the carbon atoms together into a neatly disposable clump... the burning releases an amount of energy, the reverse process takes at least the same amount of energy.

in the form of CO2 its just incredibly voluminous or incredibly pressurized or incredibly cold to keep stored.

sure you can pump it underground, but the CO2 will still diffuse... then we are just obfuscating the dump

the capture technology is useful if you power it with nuclear or windmills in case CO2 levels and global warming get out of hand. but it is not useful to capture CO2 from the power plant. it is better then to generate the energy with either renewables or nuclear directly.


Thank you for calling the CCS crowd out on their magical thinking.

The amount of CO2 we can pump underground to form carbonates with basalt rock is a drop in the bucket. Unless we find a catalyst that allows us to economically turn tons of CO2 into an inert (and maybe useful) solid or liquid, this is all going nowhere.

No reason to despair, or to stop working on solutions. But today's CCS tech, and the many variations on it, will not solve our problems.

At the moment, our best bet is improved natural sequestration. There is massive potential in better agricultural methods (cf. silvopasture, perennial crops, Upland rice, microbial farming), better land management, re-establishing grasslands in Siberia (cf. Pleistocene Park), farming in the ocean (cf. marine permaculture, upwelling restoration), etc.


I mentioned beer because the process of capturing CO2 from fermentation and re-injecting it was invented by my family a century ago and apparently was the first of its kind (according to my uncle).

My cousin and a friend of my father are working on accelerating plant and algae growth with CO2-rich atmosphere and water, in urban farms (not greenhouse) and mixed-use aqua-farming respectively. Neither have reached scale yet, but the projects seem promising -- enough that both have considered colocating with industrial CO2 emitters.

I also believe that some people are looking into re-using CO2 to store energy from solar power: focus solar rays and get CO2 to react into longer chain hydrocarbons thanks to catalyst. I’m less familiar with that process.


we all know CO2 and H20 can be recombined to form fuels, its where the fossil fuels originally came from. Where do these bacteria get their energy from? Either from photosynthesis elsewhere, or by photosynthesis themselves. In either case, in order to offset the power plant at the rate is converting fuel to electricity, you need a huge area of plants or solar to recover _all_ CO2. But then you could just remove the fossil fuel burning power plant out of the equation.

It is still perpetuum mobile...


The nuclear is much worse than coal. The public perception is different, but a few dozen big catastrophes in the coming few generations as the old reactors are pushed for too long will change all that. The thing about nuclear is that its a problem for hundreds if not thousands of years. Coal is green in comparison, when looking at the entire lifetime of repercussions.


It really depends on your values. If you honestly think the nuclear waste we produce now will make a significant difference in people's lives 10000 years, then sure it's a problem. In my opinion your epistemology is suspect, but within that value framework, it makes sense.

Regardless of the questionable assertion that people won't have figured out a way to safely contain nuclear waste 100 or 200 years from now - I'm more concerned about civilization still being a thing in 100 years from now to be worried about the effects of our waste on the cockroaches that remain when we are gone.

I think if you take an honest look at likely scenarios, Coal is not green in comparison to nuclear regardless of the relative weight you place on the value of human health and lives now vs. 100 years from now.

Nuclear is safer for the far future and is safer for people now.


Every time we talk about EVs someone tries to make this point.

Yes you can call them zero emission because they themselves produce zero emissions. This means in the city which is where the most people and the biggest problem with smog is, there are zero emissions.

One further reason that the HN crowd should understand is that it decouples energy generation from it's usage. So once you have clean energy generation you can turn off the coal and no one driving EVs will notice.


Yup, but it is still beneficial because power generation can be gradually made cleaner without affecting the rest of the infrastructure.


In addition to the possibility of cleaner power in the future; simply moving the emissions from tailpipes on the street to plants 100km from Beijing or Lagos or Mexico City... Still increases overall life expectancy.


Not zero but... consider that just the oil refinery alone uses about the same energy to make gasoline to drive one mile, as an EV uses directly to drive one mile.

EVs are hugely more energy efficient overall, which helps even if what energy requirement is left comes from burning coal.


I think the main point for China is to move the pollution outside the city streets where it directly affects more people. That's nothing to do with CO2 or global warming but to do with people's health, which is obviously super important.


Yep, it’s not zero emissions it’s like 75% less emissions (or whatever you get from adding the generator efficiency plus regenerative braking plus renewable sources.)


Fair point but consolidating pollution emitters to a single point instead of scattering them across public roads is a good thing.




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