Right, so there are a bunch of other fossil fuel burning CO2 sources that get lumped into industrial, housing, transportation, and "other" categories (basically

Right, so there are a bunch of other fossil fuel burning CO2 sources that get lumped into industrial, housing, transportation, and "other" categories (basically, all decentralized fossil fuel burning doesn't get lumped into the quarter I initially stated). A sufficiently capable renewable grid (or cheap enough off-grid generation and storage) could displace many of those uses. Skimming through the page, I'd eyeball roughly 25% (from electricity and heating), 12% (~60% of 21% industrial), 10% (of the 14% from transport), 4% (from the 6% of buildings... note that this is only counting heating and onsite energy production, not life-cycle costs), and say 5% (from the 10% of other...). That works out to ~55%. Agriculture, Forestry and Land use takes a massive piece of the pie at 25% by itself. That alone makes it difficult for renewables alone to make things work. That's why most models for net-zero include significant carbon capture projects, and why agriculture and land-use reform and conservation is so important.