Why are biomass as well as bio-oil considered CO2-neutral? Isn't it true that CO2 is released during combustion?

While it is true that the combustion of biomass produces just as much CO2 as fossil fuels, the big difference is that the raw materials for biomass have absorbed an equal amount of CO2 during growth.
Fossil fuels are also the product of trees and plants that absorbed CO2 while they were growing, but this was a process lasting several thousands of years.
The problem is that we are now returning the CO2 stored for such a long time back into the atmosphere in a relatively short period of time, so that the biological equilibrium on earth is being disturbed.


Van der Kooy Pijnacker (Bio-fuel information)