> Energy is really useful and we don't have enough to fulfil demand.

Enough sunlight falls on Earth in ~30 min to power humanity for a year. There is currently a capture constraint, not a supply constraint, which is currently being solved for.

> Unless renewables + nuclear are cheaper than carbon and not supply constrained I'd expect both sources to increase in tandem.

Renewables are cheaper than carbon, even when accounting for storage, unsubsidized. Some will say "what about seasonal!?" Not solved for yet; fossil gas for the gaps until solar, wind, transmission, batteries, and demand response/orchestration keep closing that gap. Nuclear will never be cheap unfortunately.

https://ember-energy.org/latest-updates/24-hour-solar-now-ec...

https://www.surrey.ac.uk/news/solar-energy-now-worlds-cheape...

https://www.authorea.com/users/960972/articles/1329770-solar... | https://doi.org/10.22541/au.175647950.09188768/v1

(think in systems)

> China's CO2 emissions have continued to increase rapidly along with renewables

China's emissions fell 2.7% this year. https://news.ycombinator.com/item?id=45108292 Not per-capita emissions, total emissions.

Ultimately cost is just one factor to prime driver like energy, energy security most overwhelming priority in energy trilemma (security, cost, sustainability)... Having dispatchahble power not tied to weather with abundance fuel source is always going to trump all other considerations for any serious grid. PRC got burn going ham on renewable a few years ago, few heat events that fucked over hydro production, increased AC demand and all of sudden you're dealing with opportunity cost of rationing factories that currently far exceeds $ differences in generation. Theoretically countries can size renewable rollout that minimum intermittent power + storage can reliabily power grid even with current tech, but that's like... multidecade megaproject.

Well, not forever. Global population will peak end of century (sometime between 2055-2084) and then begin to rapidly decline based on fertility rate curves. Solar PV panels can be recycled 100% today, trivially, as can lithium and sodium batteries (these materials are abundant in the Earth's crust, but only so much will be needed to establish a circular supply lifecycle loop). I suppose we can argue about the scale of mining operations. Certainly, low carbon powered mass transit whenever possible vs light vehicles and aircraft. This is Africa and India's opportunity to "do better" based on what China has accomplished (having had the chance to ride their high speed rail and ride in their autonomous vehicles) with regards to urban planning, civil engineering, and infrastructure investment, being the last parts of the world that will develop.

https://www.sas.upenn.edu/~jesusfv/Slides_London.pdf

> Not even talking about the absolutely massive mining operations we'll need to build solar and batteries

Less than we need for fossil fuels though.

It's good that ICE cars are replaced by EV over time. Even better if we have less cars overall and more mass transit.

50%+ of the world population is low to low middle income, and they're all going to want to increase emission by 4x for parity high income life styles. Realistically 8x since developing = catching up on infra build out, i.e. extremely emissions intensive fuckton of steel and concrete. IIRC 50% more than current consumption by 2050, i.e. consuming much more is basically locked in and that's based on presumption that developing countries are fucking inept and slow rolling development because they don't have a system to do a PRC modernization push otherwise we'd be looking at 200/300/400% increases in steel and concrete. Net zero is pipe dream, it's not going to happen. We can try to make the transition greener, but it's not going to be green. Ultimately, enviroment pilled brains need to remember, development/poverty reduction is going to be a net good that benefits far more people than climate change will fuck over / displace.

The United States had a chance to lead, they tried to build domestically (Inflation Reduction Act), and it was sabotaged by governance choices. Someone else has demonstrated their ability to execute and deliver. Elections have consequences. Better luck next time.

If Americans cared about the world, they would abolish their military and voluntarily lower their emissions.

Same. It pops into my head a few times per week that I haven't thought about global climate change recently, and it is because we are dealing with the more immediate thread of hypercapitalism-authoritarian-christofascism, and my neighbors in Chicago are being disappeared nightly.

Considering America is literally promoting fossil fuels over renewables and the US administration is publicly saying climate change is a scam, I think America deserves more flack than China here

China is leading the world in renewable energy production. Nuclear buildout, wind farms, solar farms. There's even some minor thermal (even though they're not geographically suited for that).

Sure, they are starting from a high number as the worlds manufacturer, but they're are clearly making strides that the other major industrial nations (the US) are not.

Can't have a discussion on climate change without the obligatory "But what about Chiiiiina!?"

It's time to own up to the fact that China is going out of their way to use renewables, and the U. S. is actively sabotaging renewable energy programs. Whining about China is starting to look pretty silly.

Look at cumulative co2 emissions though, the US created 50% of the global cumulated co2 emissions alone

Let's forget how they make almost everything we and you own.

Until not long ago, they very likely even processed your own trash.

> How does investing in new forms of energy help when old one is not decreasing?

In relation to electricity this is not the case for H1 2025, as shown in the article "Solar and wind growth exceeded global demand growth in the first half of 2025" [1]

> ...so maybe it should not?

Fair point.

1. https://ember-energy.org/latest-insights/global-electricity-...