PHA (polyhydroxyalkanoate) bioplastics manufacturing

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PHA bioplastics manufacturing roadmap

First, this technology roadmap is given a clear and unique identifier:

  • 2MPH - PHA manufacturing

This indicates that we are dealing with a “level 2” roadmap at the product level, where “level 1” would indicate a market level roadmap and “level 3” or “level 4” would indicate an individual technology roadmap within PHA manufacturing.

Roadmap Overview

Plastic pollution. Credit: ead72 - stock.adobe.com Copyright: ©ead72 - stock.adobe.com

The problem of plastic accumulation in the natural environment is becoming a high profile problem. This is because oil-based plastics, while they are cheap and have good material properties, do not biodegrade.

One potential answer to this problem is bioplastics. The term bioplastics covers a lot of different types of materials, some of which are bio-based (i.e. generated from biological feedstocks) but not biodegradable, some of which are biodegradable but not biobased, and some that are both. One family of bioplastics that are bio-based AND biodegradable is PHAs (polyhydroxyalkanoates).

The PHA family of bioplastics is both biobased and biodegradable. Source: https://www.european-bioplastics.org/bioplastic

PHAs have the potential to replace oil-based plastics in terms of material properties!

PHAs demonstrate material properties on par with some types of oil-based plastics. Source: https://www.cambridgeconsultants.com/sites/default/files/uploaded-pdfs/PHA%20-%20plastic%20the%20way%20nature%20intended_1.pdf
Another example of PHA material properties on par with some types of oil-based plastics. Source: https://www.cambridgeconsultants.com/sites/default/files/uploaded-pdfs/PHA%20-%20plastic%20the%20way%20nature%20intended_1.pdf

Unfortunately, PHAs currently are not competitive on a cost basis with oil-based plastics due to the high cost of manufacturing them.

(insert price chart here)

We propose a technology roadmap to reduce the cost of manufacturing PHA to parity or better with oil-based plastics.

Technology roadmap hierarchy for PHA (bioplastic) manufacturing


Design Structure Matrix (DSM) Allocation

Section 2.JPG

The 2-SEA tree that we can extract from the DSM above shows us that the Solar-Electric Aircraft (2SEA) is part of a larger company-wide initiative on electrification of flight (1ELE), and that it requires the following key enabling technologies at the subsystem level: 3CFP Carbon Fiber Polymers, 3HEP Hybrid Electric Propulsion and 3EPS Non-Propulsive Energy Management (e.g. this includes the management of the charge-discharge cycle of the batteries during the day-night cycle). In turn these require enabling technologies at level 4, the technology component level: 4CMP components made from CFRP (spars, wing box, fairings …), 4EMT electric machines (motors and generators), 4ENS energy sources (such as thin film photovoltaics bonded to flight surfaces) and 4STO (energy storage in the form of lithium-type batteries).

Roadmap Model using OPM

We provide an Object-Process-Diagram (OPD) of the 2SEA roadmap in the figure below. This diagram captures the main object of the roadmap (Solar-Electric Aircraft), its various instances including main competitors, its decomposition into subsystems (wing, battery, e-motor …), its characterization by Figures of Merit (FOMs) as well as the main processes (Flying, Recharging).

Section 3.JPG

An Object-Process-Language (OPL) description of the roadmap scope is auto-generated and given below. It reflects the same content as the previous figure, but in a formal natural language.

Section 3 2.JPG

Figures of Merit

The table below show a list of FOMs by which solar electric aircraft can be assessed. The first four (shown in bold) are used to assess the aircraft itself. They are very similar to the FOMs that are used to compare traditional aircraft which are propelled by fossil fuels, the big difference being that 2SEA is essentially emissions free during flight operations. The other rows represent subordinated FOMs which impact the performance and cost of solar electric aircraft but are provided as outputs (primary FOMs) from lower level roadmaps at level 3 or level 4, see the DSM above.

Section 4 .JPG

Besides defining what the FOMs are, this section of the roadmap should also contain the FOM trends over time dFOM/dt as well as some of the key governing equations that underpin the technology. These governing equations can be derived from physics (or chemistry, biology ..) or they can be empirically derived from a multivariate regression model. The table below shows an example of a key governing equation governing (solar-) electric aircraft.

Section 4 2.JPG mnavigated the globe in 2015-2016 in 17 stages, the longest being the one from Japan to Hawaii (118 hours).

SolarEagle and Solara 50 were both very ambitious projects that aimed to launch solar-electric aircraft with very aggressive targets (endurace up to 5 years) and payloads up to 450 kg. Both of these projects were canceled prematurely. Why is that?