Energy and Biogenic carbon theory
An important consideration in Product LCA modelling is energy (PERM & PENRM) and biogenic carbon content balancing. This is required for all materials that contain energy and/or biogenic carbon as an inherent property.
Energy carriers are organic materials which have a calorific value, and so produce energy when they are incinerated. For example, wood (renewable) and plastics (non-renewable). Materials with biogenic carbon content include wood, paper, cardboard, etc.
Both energy and biogenic carbon content balancing should be done in the life cycle stage where these materials leave the system, i.e., go to waste treatment. For materials where energy or biogenic carbon content does not come from the material itself (usually coming from upstream processes), for example metals, balancing of biogenic carbon is not required, while energy balancing should be done in the same life cycle stage the material enters the system.
Balancing Energy and Biogenic Carbon
There are two possibilities for energy and biogenic carbon balancing:
Manual balancing
Automatic balancing
Manual balancing
Manual balancing is done by adding balancing datapoints when materials containing energy and/or biogenic carbon as an inherent property are leaving the system. This requires finding the values for biogenic carbon and energy in the datacards to ensure the right balance.
More details about manual balancing can be found in the Academy course, including an example model (commercial user access only).
Automatic balancing
The feature can be used for automatically balancing the biogenic carbon content and energy, and can be found in the material input row by scrolling to the right of your screen, as shown below.
Four different options are available:
1a. Balance in EOL (C3, C4): to balance at end of life, where the product is sent for reuse, recycling, or energy recovery (C3) and/or disposal (C4). To be used for input materials only. Example: wooden material in A1 Manufacturing materials.
1b. Balance in Installation (A5): this is only available for packaging materials input in A3, which are usually leaving the system in A5. To be used for input packaging only. Example: pallet in A3 Packaging materials
2. Balance in the same LCA stage: this is used in different cases for biogenic carbon and energy balancing. Please refer to the attached summary table for guidance.
3. Do nothing: this is the default setting, for cases where balancing is not required or has been done manually.
Example: in A1 raw materials you input 1 kg of "Glued laminated timber production". This material will leave the system in C3 "Treatment of waste wood, untreated, municipal incineration"
Select "Balance in EoL" in the A1 raw material resource, allocating 100% to module C3 for both Biogenic carbon balancing (shown below) and Energy as material balancing.
Then add "Treatment of waste wood, untreated, municipal incineration" as the output process in C3 and select "Do nothing" for this process.
Additional information
Please note that if you have a production loss % added in A1, the Biogenic carbon and Energy as material content of the loss will automatically be balanced in A3 Manufacturing.
If you are working with construction groups, the group should be set to "Do nothing".
Currently, any biogenic carbon transfer or renewable/non-renewable energy transfer to module D should be done manually, even if the automatic feature has been used for modules A to C.
Biogenic carbon and Energy as Material features are not always set to the same option. For example, in the case of non-biobased materials such as polyethylene, in A1, "Balance in the same LCA stage" should be chosen for Biogenic carbon, as it's not biobased. This would offset possible small traces of Biogenic carbon that the datapoint might have. For the Energy as material, "Balance in EoL" should be selected, as the Energy should still be balanced when the material leaves the system.
If you have any questions about using this feature, please don't hesitate to Contact Us.