Emission issues

Question

Hello,  I am currently modelling Biomass (wood pellets) being used to generate 1MWh of electricity, using ReCiPe 2016 midpoint H, ecoinvent 3.1.1 and openLCA version 2.4.1.

The problem is, I'm currently getting a ghg emissions of 142g for the combustion of 1.25 tonnes of wood pellets via a sterling heat and power generator, I've tried using coal combustion generator, but I'm getting the same unrealistic value.

Can anyone help me out here, but possibly pointing out what may have went wrong?

Thanks.

 

Answer 1

ReCiPe midpoint H does not consider biogenic C emissions in climate change if they are not from soil or stock. Wood pellets burned emits "carbon dioxide, non fossil" which does not have a characterisation factor in the ReciPe midpoint H climate change category (I checked the ecoinvent LCIA methods but assume it is the same for the openLCA method pack).

edit: I do not understand your coal combustion part - this cannot burn wood pellets?

Comments

Thank you for your swift response, are there any alternatives for the impact method?

Also we have tried CML 2016 and have had the exact same problem, secondly we have tried using the non fossil option when selecting the flow contributions, this also gives us basically zero ghg emissions for pelletisation and energy production to make 1MWh

The only realistic ghg emissions are that of  the transport, one of which is by freight ship and other is rail.

The CO2 emission through generating the electricity in itself is zero

Essentially what im asking here is, which process best models the combustion of wood pellets when needing to generate 1MWh of electricity.