Comment by johnmorrison | Hacker News Reader

Comment by johnmorrison | Hacker News Reader

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This is true.

We should be able to reach net-zero emissions in the energy industry by around 2040 (optimistic, but realistic target), and even produce enough clean electricity to power clean electric solutions in transport/agriculture/industrial/appliance sectors (which are the other main contributors to net GHG emissions).

The only problem is that a lot of this technology is still missing / not adopting fast enough. Electric cars and cleaner farming will probably get there in time, as well as lots of electric appliances and clean steel.

I'm worried about these though:

- Cement/concrete

- Aviation (electric is on the way [1], but maybe growing too slow)

- Livestock (synthetic meat promising, but once again maybe progress too slow)

- Shipping

- Appliances/civilian buildings: long lifespan to replace systems with electric alternatives, people won't just throw away a working heating system / stove etc

For those, we need CCS or reforestation efforts to be accelerated.

Our best bet in my view is to focus most investment in nuclear energy short term, with large minorities in CCS and transport+industrial electrification, and get electricity prices super low (and TPES super high)

Once we have abundant, clean energy worldwide, we will be able to easily reach net-zero emissions and even induce net cooling if we feel we have overshot the ideal atmospheric carbon level.

(In fact, we should be able to move it either way depending on our needs)

Net zero goal isn't about stopping climate change, it's about putting the control in our hands and having the ability to shift temperatures and GHG levels in the optimal direction in perpetuity.

[1] https://heartaerospace.com (YC-backed)

> and even produce enough clean electricity to power clean electric solutions in transport/agriculture/industrial/appliance sectors

The agriculture part is overly optimistic. Agriculture entails GHG emissions from deforestation, fertilizer production, ruminant methane, NOx emissions, soil carbon depletion and other secondary effects. It's not like we can solve our problems by electrifying tractors.

> deforestation

There isn't net deforestation globally, though.

> ruminant methane

Yeah, this is one of the hardest ones to fix, but I think lab grown meat will get there eventually. Like I said, I'm not optimistic animal agriculture will have sufficient technology to eliminate most of its emissions in time - that's why we need CCS in the meantime.

My point is, the energy industry will be ready with extra capacity to power clean agriculture solutions when they are ready.

> It's not like we can solve our problems by electrifying tractors.

I don't think that's the route we should go.

Primarily indoor farming seems to be a much better long term route for plants, I prefer if we eventually get rid of most rural farmland and slowly shift it back to nature.

Cover our flat city rooftops with small farms and trees, and produce most plant agriculture indoor very close to the consumer in indoor vertical farms. Controlled environment + indoor climate, more resource efficiency, almost no risk of infections, no need for most of the chemicals we use today.

Indoor farms only work for greens and veggies, not for calorie crops. It's hard to beat free sunlight. Rooftops are not sufficient area, difficult to access and also compete for space with PV.

> There isn't net deforestation globally, though.

That would be news to me, afaik this is just a goal and hasn't been achieved yet. And as far as carbon footprint goes net zero deforestation still can release carbon overall since new forests won't be as good a carbon store as old growth forest is for a long time.

> lab grown meat

That may be useful from an ethical point of view, but has anyone shown that this can be done with a lower GHG footprint? After all those cell cultures need to be supplied with nutrients too.

If you want meat then switching from bovines to chicken is a thing you can do today. Chicken doesn't release methane, has a lower overall land and carbon footprint. Still less efficient than staple crops of course.

> compete for space with PV

PV << Fission in cities, so this doesn't matter. My hope is all green rooftops whenever possible. (I should note that this isn't trying to replace actual agriculture - it would be a small minority, the main purpose is to make cities nicer and do something with the wasted surface area.)

> That would be news to me

It's actually not news at all, we've been having net forest cover growth since we began recording it centuries ago. There's never been any long term deforestation trends on net.

(This is not to say that there haven't been awful local deforestation periods, and you're right about old forest vs. new forest, but globally it has always gone up since pre-industrial time)

> has anyone shown that this can be done with a lower GHG footprint?

It's a more physically efficient process. Why grow the whole cow and have it run around losing heat for months when you can just grow the meat you want in the end?

> Chicken doesn't release methane, has a lower overall land and carbon footprint. Still less efficient than staple crops of course.

This is all true but you can't really just replace red meat with white meat or vegetarian diet. Some try but it will never work globally.

>even induce net cooling if we feel we have overshot the ideal atmospheric carbon level.

We’re currently at ~415ppm and that this is the highest the atmospheric level has been in the entire history of humankind. Not human civilisation; humankind.

There’s no future scenario where we achieve neutrality and decide the atmospheric co2 concentration is ‘ideal’.

Apologies for sniping a single snippet of your post, but this bit stuck out to me.

I appreciate the passion in your view but this is not a wise way to think about it.

Currently, the science is not settled on whether warming has so far been net-good or net-bad.

Everything in life is a trade-off: when the temperature rises, there are more deaths due to extremely high temperatures, but less deaths due to extremely low temperatures. (This is just an analogy, there are countless actual examples of trade-offs in this case)

It may very well be that warming has up until this point, and perhaps even for a little longer, has been and will be a good thing overall. The world has been a lot warmer and a lot colder in relatively recent times.

I'm far more concerned about the effects of air pollution, acidification etc than a slight increase in temperatures (do not misinterpret: I say more concerned, both are concerning)

> You understand that we’re currently at ~415ppm and that this is the highest the atmospheric level has been in the entire history of humankind?

This is also highly misleading. We were well above 500ppm for the entirety of 50mya - 250mya.

Homo sapiens is extremely young, we are born of an ice age. 415ppm is among the lowest CO2 concentrations of all time, ever.

>Currently, the science is not settled on whether warming has so far been net-good or net-bad.

When you only have a single Petri dish in which to make observations, and you also happen to eat your lunch out of that same dish, waiting for the science to lock into even greater certainty than that which has been established over the last fifty years or so is a less wise way to approach the matter. Observations of biodiversity loss are, for me, sufficient to move beyond the debating and towards the changing phase.

>I'm far more concerned about the effects of air pollution, acidification etc than a slight increase in temperatures (do not misinterpret: I say more concerned, both are concerning)

Also greatly concerning, but elements of the same whole which needs to be addressed. I think we’re on the same page here - my overall position is that singular focus on targeted solutions for only one aspect of the problem ignores the wider picture and will likely lead to second-order effects which cannot be foreseen.

CO2 as far as air pollution goes it is a nasty topic also. We’re starting to understand the impact of CO2 on human cognition at the local scale. If we consider that the removal of lead from petrol was linked to a significant down-turn in human aggression, what’s the world going to look like if the entire population runs 24/7 with the equivalent of a morning headache, effectively dropping the global IQ by a significant amount?

> Homo sapiens is extremely young, we are born of an ice age. 415ppm is among the lowest CO2 concentrations of all time, ever.

From an anthropogenic POV I’m not sure how this is a good thing. It’s higher than its ever been in the period that allowed humans to develop.

That’s assuming we’re talking about humankind and society as the thing we’re really seeking to save here.

We could also talk about biodiversity, but then the rate of change is probably a more significant element than the resting level. We’re spiking the level at a rate only previously seen during mass extinction events, and it follows that if we did want to draw back down to a lower level again for the purpose of allowing life to flourish again it probably couldn’t be at the same rate.

> Observations of biodiversity loss are, for me, sufficient to move beyond the debating and towards the changing phase.

There's a lot wrong here.

(a) Over the past two centuries, we've been doing hundreds of crazy new things we've never done before. Correlation =/= causation: you can't just assume biodiversity loss is mostly caused by atmospheric carbon (btw: it's not)

(b) You're painting me as a caricature that has no link to reality. I'm not "waiting for science to lock" and spending my time "debating" instead of taking action, I've been working on clean energy development&commercialization for almost my entire career, and it is my primary long term focus in life.

That being said, I think there's very good reason for other people to spend time debating these issues instead of just rallying for radical political fixes to CO2 emissions. Like I've been trying to explain, the science is not at all settled on the subtleties of what we should do long term.

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> Also greatly concerning, but elements of the same whole which needs to be addressed. I think we’re on the same page here - ... effects which cannot be foreseen.

I completely agree with you here - you're absolutely right.

You also bring up very good points about why increased CO2 is nasty - these are accurate and CO2 is fundamentally a toxic gas so of course I'm also leaning towards the "the ideal level is probably below today's level" side - but I don't know yet. With so many different factors to consider, we can't just look at any one thing like human cognition and ignore the other pros / cons.

> That’s assuming we’re talking about humankind and society as the thing we’re really seeking to save here.

I don't think we need to "save" humankind or society (or the planet) - all three of those things are extremely resilient. Some portion of humans will survive just about anything with maybe the exception of a nasty gamma ray blast.

My concern is that GHG emissions will probably cause countless millions of avoidable deaths, negatively affect billions of human lives and cost us trillions of dollars long term in addition to ruining the natural environment and biodiversity.

This is, however, a slow process compared to a human lifetime. It's a really slow, big problem that will do a lot of damage if we don't focus on solving it before it becomes even worse.

> We could also talk about biodiversity

I'm very unsure whether GHG emissions are a leading cause of biodiversity loss in recent years. We do so much other bullshit (global shipping alone basically destroyed the natural barriers between ecosystems) and have already plunged nature into a mass extinction before the industrial revolution even began iirc

There's a lot of things humans do that cause extinctions. We should probably be addressing all of them.

With you on all points. Sorry for the caricature, wasn't intended as a personal judgement.

Thanks! I think we've reached a productive agreement.

I do share your frustration with skeptics in life who just debate, I think this is a natural frustration for people who have an action bias and prefer to make things happen.

The world will always need those kinds of people, though, to keep us on the right track.

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