In this paper we provide an overview of the most important emerging groups of bio-based polymers for bulk volume applications and we discuss market projections for these types of bio-based polymers in the EU, thereby distinguishing between three scenarios. Bio-based polymers are projected to reach a maximum of 1.75–3.0 million tonnes by 2020 in the EU-25 under very favourable conditions. While these are sizable quantities, they are modest compared to the expected production increase of petrochemical polymers. Thus, the market share of bio-based polymers will remain very small, in the order of 1–2% by 2010 and 1–4% by 2020. Energy and greenhouse gas (GHG) emission savings from bio-based polymers were found to be 20–50 GJ/t polymer and 1.0–4.0 t CO2 eq/t polymer compared to petrochemical polymers. Bio-based polymers are thus very attractive in terms of specific energy use and emissions. In absolute terms, savings are rather small: as a proportion of the total EU chemical industry, energy savings amount to 0.5–1.0% by 2010, up to a maximum of 2.1% by 2020. Bio-based polymers therefore cannot offset the additional environmental burden due to the growth of petrochemical polymers (there is a gap of a factor of about 20 to 40). The relatively low contributions compared to the total EU chemical industry are caused by the low production volumes of bio-based polymers compared to petrochemical polymers until 2020. While the growth rates of bio-based polymers are high, the low starting level entails that a longer time period is required until meaningful substitution levels are observed. Nevertheless bio-based polymers represent a worthwhile strategy by gradually reducing the environmental burden as a consequence of replacing fossil resources with bio-based resources. The developments outlined should be seen as the first steps towards a sustainable chemical sector.