PRC extracts ~4 million barrels per day, they're a continental sized land power with resources, not JP. IIRC US military consumes 90 million barrels per year / 240k barrels per day. PRC domestic consumption is 14m barrels per day. ~6m goes to transportation, 2m goes to heating, both in process of being electrified. 2m goes to other. Industry, uses ~4m barrels, of which PRC MIC uses relatively little as % of output relative to behemoth that is entire PRC manufacturing/industry. TLDR short/medium term, they can ration transportation, focus industry on MIC, and sustain military multiple times their current size on wartime economy, indefinitly. Medium/long term with rapid electrification and some RU piplines they can operate normally. There's also estimated 300m barrels and growing in strategic reserves. And that's assuming US blockades PRC MENA oil, in which case US refineries on CONUS probably going boom. It doesn't matter how much oil you have in the ground if you can't protect your extraction infra. Entire PRC Malacca dilemma assumes US can choke PRC SLOC unilaterally with little consequence to herself, the calculus changes when CONUS serenity is on the line, which looks like PRC end game when they indicated they're pursuing conventional global strike program a few years ago.