This particular scandal, though, is that these companies are overstating the SPF rating on their sunscreens, and it looks like the mineral sunscreens are worse on that front.

Forests cannot grow faster than trees decay forever.

Maybe not forever as in the heat death of the universe, but I don’t see why timber can’t be a carbon sink for timelines longer than humanity.

There are structures made of wood that have been standing for over 1000 years. There are lots of structures made of wood that have been standing for over 500 years.

Hominid-harvested wood still exists in archaeological sites dating back from before homo sapiens emerged as a species

And coal is basically timber and other plant matter that has been sequestered underground and subjected to pressure, heat, and time.

Plants can provide a carbon sink that lasts long enough to remove atmospheric carbon indefinitely, especially with modern engineering (making carbon-rich soil with charcoal dust, manufacturing cross laminated timber as a building material that should last centuries, if not millennia, etc.).

But if you kick the can down the road such that the original field where the trees were grown can grow more trees, the your carbon sink can remove atmospheric carbon on net at a rate faster than it releases carbon back into the atmosphere.

Also, solar and wind are intermittent, and therefore not ideal for dealing with real-time grid demand. However, that may make them ideal for passive carbon capture

I think that’s a huge part of the long term solution: intentionally building overcapacity so that lower production days still produce enough energy to meet needs, but especially sunny or windy days have surplus that needs to be used. If the intermittent energy surplus meets a carbon-fixing method to consume that surplus energy, then we can have carbon capture without that energy use displacing a reduction of greenhouse emissions elsewhere.

My question is, wouldn’t the power needed to run these negate the benefits they bring?

The hardest part about green energy is getting it to the time and place where it can be most useful. That’s why real time solar power prices sometimes dip negative (where the producers are literally paying people to take that excess power off the grid), and sometimes in consistent and predictable ways (e.g., California’s “duck curve” in spring and autumn).

So with solar power being the cheapest form of generation, but highly dependent on weather conditions, the solution might be to build up overcapacity where production during cloudy days is enough, and then find some way to store the excess on sunny days for nighttime, and maybe using intermittent power sinks that can productively use energy only when the production is high (charging batteries, preemptively cooling or heating buildings and storing that for later, capturing carbon, performing less time-sensitive computer calculations like data analysis for science, etc.)

If we have systems that produce too much energy, then carbon capture (including through manufacture of fuel or other chemical feedstocks) can vary by time of day to address overcapacity.