According to the IPCC (Intergovernmental Panel on Climate Change) when calculating CO2 emissions from burning or otherwise processing biomass we should count it as neutral. The rationale for this comes from a stand that CO2 emitted by burning biomass will be eventually absorbed by the plants.
In a time when lowering CO2 emissions is paramount for saving the planet this sounds counterintuitive. That is because it is, but not because of the reason you think it is.
It is worth mentioning that many scientists disagree with this policy and this is our contribution to the ongoing argumentation on how to change this stand.
There are two aspects to this problem. By supporting this principle you are giving a mandate to all actors who use wood or biomass for heating, to continue emitting CO2 into the atmosphere.
Without this mandate, they would need to switch to other renewable sources of energy (electricity from wind and solar, or use hydrogen as an energy carrier made from wind and solar.) I will not debate the economics of this as this is not the point of this argument although market statistics show that electricity from wind and solar is the cheapest one.
Another important factor is that by excessively using biomass for energy we are destroying the ecosystem, one thing we are bound to protect from the negative effects of climate change. Not to mention that we are polluting the air.
The other aspect that explains the wrongfulness of the assumption that releasing CO2 from the atmosphere is neutral is the one that humans have broken the balance of the natural ecosystem.
Before the industrial revolution, which we take as the point in time when humanity began altering the balance of the ecosystem there were certain levels of CO2 in the atmosphere. The commonly agreed number is 280ppm and it was mostly constant for the last 5-6000 years. In that time humans have (along with natural causes) burned wood and biomass for heating and cooking. Despite all of this activity levels of CO2 remained stable.
After the industrial revolution levels of CO2 began to soar and are now over 400ppm resulting in an average temperature rise of 1-1.5C. Anything above 0,5C is considered dangerous and the sole mission of the IPCC is to prevent this from happening.
During the last 150 years, the world has lost more than 1/3 of its forests. This means that we have a negative balance. If we would be able to acheive the level of land forest occupied 150 years ago we could be in a possition to start using the neutral formula for the usage of biomass for heating (i.e. burning and releasing CO2).
Even then we would need to put a limit on how much wood we can burn as it has to be balanced with the number of trees we can plant and its ability to sequester CO2 from the atmosphere.
The solution to this dilema would be, as we explained, to rigorously start tracking every tree we are logging and start systematically on a worldwide level planting trees ie. restoring forests. After we have restored the balance we had 150 years ago we will be able to start counting CO2 emissions from burning wood and biomass and CO2 neutral. Of course, we should do it in a controled manner.