I hate to be that guy, but the only reliable way to reduce greenhouse gas emissions is to drastically reduce emissions. Switching to biofuel doesn't fix climate change because biofuel is still terrible. Switching to electric cars doesn't fix climate change because electric power is still terrible (not to mention all the damage from lithium mining, manufacturing and battery replacements).

The only solution is to make neighborhoods more walkable, reduce the need for frequent travel through mixed use zoning and invest in public transit (trains and trams, buses if you can't avoid road traffic completely) so more travel happens in high density vehicles rather than cars.

But that basically means public spending for public services rather than having companies sell more products to consumers and that's just too much like communism to be a legitimate answer because you don't want people to reconsider whether some aspects of socialism might actually be good.

EDIT: Since HN won't let me reply, I'll just pre-empt any further replies by pointing out that the problem with "solutions" like renewables, carbon capture and electric vehicles is that while they sound great in a spreadsheet they ignore externalities, overhead and scale: yes, if we could wave a magic wand and convert all existing cars into electric and backfill the increases energy demand by turning all the now unused infrastructure into wind mills and solar panels and somehow fix the energy storage problem, the situation would undeniably be better than it is now. But that's not how we get there and even that situation would be unsustainable as long as we follow a growth mindset and promote individual transportation as a consumer product rather than addressing infrastructure as a social issue.

I don't think HN is ready to acknowledge that the biggest carbon emission savings in the US don't come from carbon capture tech magic but from offloading the more emission heavy parts of the production chain behind the curtain into third world countries that don't end up on the spreadsheet. We're not going to solve climate change by stuffing all our toys into the broom closet with hopes that the regulators can't see the mess we made. We need to actually clean up the mess and stop adding to it. We can't fix a resource problem by continuing to expend an increasing amount of resources. It's called "reduce, reuse, recycle" because those are the things you can do in decreasing order of effectiveness. Carbon capture is just recycling. Going electric is not even that.