Not the CO2 - the C. Technically you don't need the Cs at all, you can just burn H2. However, H2 has all sorts of annoyances; running a car on H2 is difficult. Running a boat on it, not really feasible right now.

Your worry about the 'gap' is sensible but (probably) not relevant here.

You're asking to do the job of 'produce energy in a sustainable way' and the job of 'use said sustainably produced energy efficiently' in tandem, never raising one without also raising the other on the same day.

Not. Possible. This market is already far too complicated. So, instead, you work on one of the 2 edges and trust that the market will fix the other edge. If not immediately, then at least create a stable incentive.

For example, right now, solar and wind is generally considered 'cheapest', but that glosses over an important detail: When the sun is out and it's windy, power prices are often __negative__ for it. So cheap, it's negative. That's because so much solar and wind is produced, the demand side hasn't caught up. Power MUST be used IMMEDIATELY, you can't just 'let it go round and round on the power cables', they'd just asplode. If there's a sudden unplanned influx of power then that's bad and thus you get money _back_ if you take more power off the grid in that time. And, the flipside: ON a misty day (no wind, no sun), power is very expensive. Because supply is lower than expected. (Prices go negative because not all solar/wind systems are smart gridded up; if they were, they'd just turn themselves off and stop producing. Which merely reduces the price to 0 instead of negative).

Hence, one of the big missing links in this future renewable energy world we're trying to make happen, is an energy _demand_ that can react perfectly to the inherently fluctuating nature of energy _supply_ where the supply is based on solar/wind.

One solution is to add a really stable or flexible source on the supply side. This is partly why richer countries still are building gas-based fossil fuel powerplants: Gas plants are easily 'tunable' - you can pretty much just rotate a volume knob and the power output responds pretty quickly. Coal is harder to 'tune', and nuclear is MUCH harder to tune (twiddle the knob now, it has an effect hours from now). Regardless of the tuning, a fossil fuel powerplant, even one that is usually running at nearly zero flow, is something we'd prefer to avoid.

So, a better solution is to instead have flexible demand that can respond to fluctuating supply. But that's really hard to do!

The solution so far is to let the grid mediate: Folks producing power just shove it on the grid, prices respond to supply, and the hope is that the cheap (or even negative!) arbitrary price drops incentivize the market to come up with ways to use the free power when its there.

This is sort of working but the biggest issue is the grid part. It's actually really pricey to build a grid that can deal with massive spikes, and the exact places where you want to build wind and solar (far away where there's plenty of space) is where there is no grid. Because nobody lives there.

Methanol offers an enticing way out. Instead of building, say, a wind farm in an urban area (complicated), or a wind farm where there's plenty of space (but no grid connection that can deal with it), you build a wind farm out of the way and hook it up to a methanol factory. You just store the methanol (it's easy to store - liquid and not all that poisonous or volatile), you can even pump it, you can ship it.

The amount of research and money flowing into this model of 'make fluctuating renewable energy sources and hook em up to methanol producing things built right next to them' is limited because the demand for it isn't all that high. But it's not all that technically challenging (within reason. My point is, this is WAAY easier than nuclear fusion, for example) - so, create stable demand for it and it's highly likely the market will provide.

Hence, it's oversimplified but in broad strokes fair to call methanol 'low emission' even if methanol supply today isn't great.