this post was submitted on 26 Nov 2023
88 points (100.0% liked)

Climate - truthful information about climate, related activism and politics.

5243 readers
303 users here now

Discussion of climate, how it is changing, activism around that, the politics, and the energy systems change we need in order to stabilize things.

As a starting point, the burning of fossil fuels, and to a lesser extent deforestation and release of methane are responsible for the warming in recent decades: Graph of temperature as observed with significant warming, and simulated without added greenhouse gases and other anthropogentic changes, which shows no significant warming

How much each change to the atmosphere has warmed the world: IPCC AR6 Figure 2 - Thee bar charts: first chart: how much each gas has warmed the world.  About 1C of total warming.  Second chart:  about 1.5C of total warming from well-mixed greenhouse gases, offset by 0.4C of cooling from aerosols and negligible influence from changes to solar output, volcanoes, and internal variability.  Third chart: about 1.25C of warming from CO2, 0.5C from methane, and a bunch more in small quantities from other gases.  About 0.5C of cooling with large error bars from SO2.

Recommended actions to cut greenhouse gas emissions in the near future:

Anti-science, inactivism, and unsupported conspiracy theories are not ok here.

founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 1 points 11 months ago (1 children)

Since 95% of current hydrogen production is from fossil fuels with no foreseeable scalable replacement, the benefit is profits for fossil fuel companies who wouldn't make money off those of those proven methods.

[–] ocassionallyaduck 7 points 11 months ago (1 children)

This is largely FUD. Previous industrial H2 use made H2 as a Natural Gas or Methane derivative.

Hydrogen production from electrolysis is being expanded. Hydrogen is favored over other fuels because while it can cause enbrittlement, that can be accounted for by using materials resistant to that. It's how we've handled hydrogen for decades till now, just not in the retail sector, but also why it would not be pipelines around the country like Natural Gas is with the same pipes. This is a solved problem.

Hydrogen when used in a fuel cell or in a hydrogen combustion engine produces 0 or near 0 emissions. That is one of the biggest appeals here. The emissions of a hydrogen fuel cell is water, H2O. You can drink from the tail pipe (don't). In HICE engines, the emissions are a microscopic amount of NOx fumes, in a different world from existing gas or diesel engines.

This positions hydrogen as a much more scalable and less polluting fuel than even batteries long term. And much, MUCH lighter than batteries of similar power density. These are the appeals.

Also, while volatile as a molecule, it's also quick burning and the smallest molecule on the periodic table. Meaning a 700psi tank that has a 2in tear in it, would entirely vent /burn in around 30seconds to 1 minute. Because the molecule can literally leave faster. Unlike the never ending fires that EVs have when they light up, a H2 fire is over rapidly. There are also safety measures like quick disconnects involved. Finally, the tanks are carbon fiber wrapped and reinforced, and the tank of the Toyota Mirai can resist fire from a AR-15 directly. Puncturing these is hard.

[–] CADmonkey 3 points 11 months ago

In HICE engines, the emissions are a microscopic amount of NOx fumes, in a different world from existing gas or diesel engines.

Much less NOx, and we already have technology to reduce NOx for gasoline or diesel engines. Even better, because what usually hurts the systems used to reduce NOx is soot from the exhaust. There will be almost none of that on a hydrogen engine.