Polyhydroxyalkanoates (PHA) production in a circular CO2 economy: it's role in mitigating global CO2 emissions
Bibliographic record
Abstract
• A universal carbon footprint model demonstrates that PHA production results in negative emissions. • The cradle-to-grave carbon footprint of PHA derived from waste cooking oil can be reduced to half that of fossil-based plastics. • Compared to fossil-based plastics, PHA production shows lower impacts on resources, ecosystems and human health even when green electricity is not fully available. • With a carbon tax credit, PHA production would be 11 % more cost-effective than fossil-based plastics. • 83 % of CO 2 equivalent emissions from the plastic industry can be mitigated through the use of alternative PHA combined with advanced recycling technologies. The use of fossil-fuel derived plastic significantly contributes to resource depletion and global warming. This study provides a life cycle assessment of PHA production, including (1) fully transparent in-plant data with a cradle-to-grave scope, (2) a universal life cycle model with varying input variables to ensure results are adaptable to different scenarios, (3) optimization pathways for both environmental and economic aspects, and (4) forecasts of potential impacts and compare with recycled plastic across different future timelines and locations. The cradle-to-grave carbon footprint of PHA is determined to be 5.77 kg-CO 2 e/kg-PHA today - nearly equivalent to that of conventional fossil-based plastics (5.52 kg-CO 2 e/kg-plastic) – however, with reasonable improvements projected for 2030/35, PHA would result in a carbon footprint of 2.01 kg-CO 2 e/kg-PHA. The cost is also found to be similar ($1168/t vs $1320/t).
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".