Carbon positive: Produce MORE CO2 than you consume
Carbon neutral: Produce same amount of CO2 as is consumed
Carbon negative: The green plants consume more than is produced by the ugly carbon units.
Anybody who believes the DimWIT's carbon story of glowbull warming is an idiot.
The second step is the captured sunlight energy has to be deep-sixed in the ground, initiating the process of making coal, else the carbon will soon be returning to life.