Bioplastics have much in common with conventional plastics. Two main characteristics separate bioplastics from conventional plastics: 1) The use of renewable biomass materials in the manufacture of bioplastics. Bioplastics are manufactured from sources such as starch and vegetable oil rather than fossil fuel based plastics which are derived from petroleum. 2) the biodegradability and compostability of bioplastics. Some, but not all, bioplastics are biodegradable or compostable. The aim of the bioplastics industry is to close the production loop, mimicking nature's example (as indicated in the introduction image).
Most biodegradable bioplastics are used for disposable items such as packaging or organic waste bags. Nondisposable applications include items such as mobile phone casings, carpet fibres and car interiors. In these areas, the goal is not biodegradability, but to create items from sustainable resources.
Initial research into bioplastics started several decades ago. Novel biodegradable bioplastic products have been on the market in Europe for about a decade (European Bioplastics, no date). Mostly, these products are compostable biowaste bags and loose fill. The expansion of production plants for bioplastics resulted in the dynamic development of the market for packaging film since around 2002 (European Bioplastics, no date).
Like with conventional plastics, the application spectrum of bioplastics is very broad. Several applications have already established themselves successfully in important markets. Figure 2 shows several segments of the economy in which bioplastics have already successfully been established. Many of these bioplastic products are being used in areas where compostability is a significant benefit. Commercial success occurs above all when the particular properties can be transformed into useful product functionality and added value (European Bioplastics, no date).
[media:image:2]In 2007, global production capacity of bioplastics was estimated to be 0.36 Mt (million metric tonnes), and constituted approx. 0.3 % of the worldwide production of all plastics (PRO-BIB, 2009). Current worldwide production of plastics is dominated by petrochemical plastics. However, the bioplastic market has been experiencing dramatic growth: from 2003 to 2007 the average global growth was 38 % (PRO-BIP, 2009). In Europe, the market even grew with 48 % over the same period (PRO-BIP, 2009).
According to the PRO-BIP study the bioplastics industry is at the beginning of the S-shaped learning curve. Although newly constructed plants are still small, they are rapidly increasing in size. Therefore, it will not be long until turn-key plants with production capacity similar to conventional plastic production plants will be commercially available (PRO-BIP, 2009).
The video below, made by the Massachusetts Institute of Technology, gives a basic introduction to bioplastics and its advantages over conventional plastics.
The total technical substitution potential of bioplastics is estimated to be 270 Mt, or 90 % of the total polymers that were consumed in 2007 (PRO-BIP, 2009). However, it will not be possible to exploit this potential in the short to medium term, according to the study, because of economic barriers, technical scale up challenges and the need for time for the industry to adapt to the new plastics (PRO-BIP, 2009). But the authors of the PRO-BIP study stress that the potential of bioplastics is very large, and that future developments might increase the potential.
Current status of the technology of bioplastics is illustrated in figure 3. It can be seen that the sector is characterized by high growth and strong diversification among different bioplastics. Number of materials, applications and products, number of manufacturers, converters and end users has increased considerably over the last years. In addition, significant financial investments have been made into production and marketing and are expected to be made in the years to come.
From a geographic point of view, the U.S. and Europe are leading in the bioplastics production (See Figure 4). However, the geographic distribution has changed to a more balanced distribution among the world regions (PRO-BIP, 2009). For instance, the U.S. share of production decreased from 84 % in 2003 to 33 % in 2007. Europe's share increased over the same period from 15 % to 36 %. The Asia-Pacific region and South America have upcoming markets. This development is illustrated in figure 4.
[media:image:4]Based on company announcements, the geograhic distribution is expected to further balance out over the regions of the world (PRO-BIP, 2009). Figure 5 illustrates the estimated geograhic distribution per world region in 2020 based on the company announcements (PRO-BIP, 2009). A long and sustained growth trajectory of production and demand for plastics is expected in the developing world (PRO-BIP, 2009).
[media:image:5]Next to the advantages of conventional plastic (such as being lightweight and multifunctional) bioplastics have certain other advantages that can contribute to socio-economic development and environmental protection. Because bioplastics are made from renewable resources the use of fossil resources is limited. In addition, the biodegradable aspect of some of the bioplastics can be useful in developing countries with arid conditions where the soil lacks humus. Composting the plastics would provide fertiliser and substrate to improve the soil quality (European bioplastics, no date). Moreover, the biodegradability of bioplastics reduces the stress on landfills.
Currently, no CDM projects have been registered by the CDM Executive Board  that address the shift from the production of conventional plastics to bioplastics. As noted, such a shift would prevent the emissions of GHG as bioplastics are produced from a renewable resource. As of July 2010, no CDM methodology exists that would support the shift in production from petrochemical based plastic production to bioplastics.
However, there are certain situations in which a project could potentially apply for CDM status. For instance, when the biomass used for the production of the bioplastics is derived from biomass waste streams the project would prevent GHG emissions as it prevents the biomass decay. The following methodology might be suitable in this situation: 'Avoided emissions from biomass wastes through use as feed stock in pulp and paper production or in bio-oil production --- Version 2.2'. This methodology assists in the calculation of the avoided emissions because of the prevention of the decay.
Because petrochemical based plastics have been developed and used extensively for over seventy years they are relatively cheap compared to bioplastivs. While there are a number of bioplastics with great potential, and unique features, to compete in a wide range of applications currently dominated by petrochemical based plastics, certain barriers still exist that prevent this from happening. Ideally, to compete, a bioplastics should be environmentally sustainable, inexpensive and functionally equivalent to conventional plastics. Usually bioplastics are both environmentally friendly and sustainable, but they are still relatively expensive and they can't replace petrochemical based plastics in some applications (Barker & Safford, 2009).
Currently, bioplastics are two to four times more expensive than conventional plastics (Barker & Safford, 2009). Barker and Safford identify several reasons for this: 1) there is a high cost for the plant production, 2) a high cost of the raw materials used, 3) the current smale scale of production doesn't provide economies of scale, and 4) the research and development costs of bioplastcs are high (Barker & Safford, 2009).
The price of conventional plastics is linked to the price trend of oil, as byproducts of the petroleum industry are key ingredients for production of plastic (Barker & Safford, 2009). Because bioplastics are based on another resource bioplastics are not linked to the fluctuating oil price. Bioplastics are therefore not accompanied by the high price volatility of oil. According to the European Bioplastics organization current economic competetiveness of bioplastics is restricted by high development costs and lack of economies of scale for mass production. Mass production of bioplastics is expected to increase economic competetiveness. As can be seen from figure 2, and from the statement that it is likely that bioplastics production is at the beginning of the S-curve, it seems likely that economies of scale will be reached in the near future. In addition, forecasts on the development of crude oil prices illustrate that rising oil prices will make use of renewable resources increasingly economical in the future (European Bioplastics, 2009).
Barker, M., & Safford, S., (2009). Industrial uses for crops: Markets for bioplastics. Project report 450: HGCA. Retrieved on 16 July 2010 from: http://hgca.co.uk/publications/documents/cropresearch/PR450_Final_Project_Report.pdf 
European Bioplastics, no date. The association European Bioplastics, based in Berlin, website: http://www.european-bioplastics.org/index.php?id=189 
PRO-BIP, (2009). Product overview and market projection of emerging bio-based plastics. Authors: Shen, L., Haufe, J., & Partel, M., Copernicus Institute for sustainable development and Innovation at the University of Utrecht. Commissioned by European Bioplastics and the European Polysaccharide Network of Excellence. Retrieved on 9th of July from: http://www.european-bioplastics.org/index.php?id=191