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Opinion Agricultural

Opinion Agricultural Resources for Bioplastics Feedstock for bio-based plastics today and tomorrow By Michael Carus CEO nova-Institute Achim Raschka biotech expert at the nova-Institute Hürth, Germany 1 st and 2 nd generation crops: Pros and cons To produce bio-based plastics there is a broad spectrum of feedstock options. Today biobased plastics are mainly based on sugar, starch, plant oil and natural rubber, the so-called first generation feedstock. Because of potential competition with food and animal feed politicians and scientists have introduced, in the last ten years, the idea of using lignocellulose feedstock by transforming it into fermentable sugar (whether this will have less impact on food security will be discussed below). Lignocellulose means wood, short rotation coppice such as poplar, willow or miscanthus, or lignocellulose containing agricultural by-products. Another option is to use by-products which contain sugar and starch. The following table shows the pros and cons for different feedstock options: Criteria Yield per hectare in terms of fermentable sugar equivalents Green House Gas Emissions for biomass derived Bio-based Plastics (cradle to factory gate) First Generation (Sugar, Starch, Oil, Natural Rubber) Second Generation (Lignocellulose – Wood and Short Rotation Coppice) Broad range, but more or less on the same level Broad range, but more or less on the same level Technical maturity Very high Still a lot to do Economically competitive Secure supply with raw materials at a reasonable price Not yet (except for specific properties) Competing for food, animal feed and bioenergy Not yet Competition with bioenergy and traditional industrial material use By-products from agriculture and forestry If the by-products have no markets yet, this means an extra yield Very low, because of the methodology of LCA Depending on the content of the by-product Not yet, but close Still a huge potential for inefficiently used by-products, or even those not used at all Direct competition with food and feed Yes No No Indirect competition to food and feed Yes – on land use No Emergency reserve for food and feed Yes No No Feedstock for Bio-based Plastics and Composites (source: nova-Institute) Second Generation Lignocellulose Saccharification First Generation Sugar Starch Plant Oil Natural Rubber feedstock Natural Fibres Wood Timber Byproducts Lignin Wood Plastics Composites for example bagasse Natural Fibres Reinforced Plastics Compressionmoulded parts Biobased Plastics thermoplastics or thermosets biodegradable or permanent Elastomers biomaterials Carbon Fibre 44 bioplastics MAGAZINE [06/11] Vol. 6

Opinion The table shows in a clear way that there is no easy answer. Are second generation feedstocks really a better solution? To answer this question on a solid scientific base nova will conduct a multi-client study in 2012/2013: What is the best sustainable feedstock to generate fermentable sugar? Interested companies and associations can still join the advisory board. Non-food discussion Forced by the public discussion during the food crisis in 2008 politics and industry gave a very simple answer to the potential food versus industry conflict: Industry should only use non-food crops as feedstock. From our point of view the question of food versus non-food crops for industry is itself oversimplified and misleading. The real questions and conflict are different: • Question 1: Are there - in the EU, in the member states or in the region – free agricultural areas left, which are not necessary for food and animal feed, domestic use and export? If yes (and in many regions the answer is yes), continue: • Question 2 (the real question): How can we use these free areas for industry with the highest resource efficiency and the highest climate protection? • In many cases food crops will best fulfil these criteria - just because they have been specially cultivated to produce maximum yields over many, many years and all logistics are established. • Food crops for industry can also serve as an emergency reserve for food and feed supply – second generation lignocellulose cannot! This is exactly what is happening this year in Brazil. The Brazilian government has reduced the bioethanol fuel quota to save sugar for the demanding food and feed market. So ‘No food crops for industry’ can lead to a misallocation of agriculture resources. We need a comprehensive concept for feedstock for food, feed, industrial material use and bioenergy. The amount of land needed to grow feedstock for bio-based plastics - How much is needed, and how much will be needed in the future? Both answers to the above questions show how the agricultural area is used today. Most of the arable land is used for animal feed (69%), followed by food (17%), material use (7%, including bio-based plastics) and finally bioenergy (3.5%). The data on biomass in tonnes look slightly different and the main reasons are different yields per hectare for different crops, dedicated to certain applications. For example cotton, the leading crop for industrial material use, has considerably lower yields than most of the energy crops. Using the recent data from Prof. Endres (FH Hannover) and European Bioplastics, today (2010) about 724,000 tonnes of bio-based plastics are produced, and this will increase to 1.71 million tonnes by 2015. According to a rough average estimation 2.5 tonnes of bio-based plastics can be produced per hectare and per year. This means that crops for bio-based plastics were grown on 290,000 hectares (0.02% of global arable land) in 2010 and will be grown on 684,000 hectares (0.05%) in 2015. To substitute all 250 million tonnes of plastics in the world with bio-based plastics will demand 100 million hectares or 7% of the global arable land. This will only happen when crude oil is really scarce and very expensive. Then solar and wind energy will also be taking over the energy sector, including bioenergy, so these arable areas will be set free for bio-based chemicals and plastics. Global land use for food production and renewable resources 2008 (source: nova-Institute) Use of harvested agricultural biomass worldwide (2008) (source: nova-Institute) Total land area world wide 13.4 bn. ha cities, residental area, 0.2 road and rail Arable land world wide 5.0 bn. ha Cropland world wide 1,500 mn. ha Total biomass ca. 10 billion tonnes Biomass for industrial material use 4,3 % Biomass for energy use 3,7 % waste land (deserts, mountains, ...) 4.3 3.55 pastures 260 Food 18 % Food forest 3.9 1.030 Feed agricultural area 5.0 1.45 cropland today 55 100 Bioenergy Material use 74 % Feed in bn. ha in bn. ha in mn. ha Allocation of biomass to production target (main product). Respective amounts include raw materials and by products, even if their use fall into a different category. bioplastics MAGAZINE [06/11] Vol. 6 45

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