Feedstock sources and supply

Availability of economical feedstock, feedstock flexibility and security are essential. Globally, though not regionally, supplies are insufficient for domestic biodiesel production. Strong partnership with the vegetable oil industry (preferably with on-site crushing facilities) is critical to producer survival. No one feedstock provides the ultimate solution to the biodiesel industry’s challenges. A diverse portfolio of agricultural products for biodiesel is needed. Diversification of the feedstock basis is an ambitious goal. There are rising demands for lower-cost feedstocks (used vegetable oils, tallow), posing collection problems. The use of human food/animal feed for production of biodiesel is a short-term solution only. Investment in exploration and cultivation of alternative, large-volume, high-yield, non­food, non-rainforest-based lipid feedstocks (e. g. jatropha, pongamia, algae) is required. Development of additional feedstock sources with relatively low input requirements (e. g. crops growing in a dryland farming setting) is much needed as well as recultivation of degraded land, waste land and white deserts by oil-bearing plants. The answer to the supply problem, crucial for the success of the biodiesel strategy, is more beans, more means, change genes. Transgenics are imperative for biofuel crops. It is important to use green gene technology for developing better energy plants. Increased adoption of hybrids, high-yielding genetics, new traits and improved production practices will create more value through higher yields and better stress tolerance. Obvious approaches to easing the supply response are dramatic improvements in agricultural (oilseed) yields and oil content of conventional crops, introduction of additional crops into crop rotation schemes and/or increasing the acreage of land farmed. Increasing inter-crop competition for acreage has recently been observed, notably in the US. Increased crop yields are of particular importance because they affect the amount of land needed to meet food, feed and fibre demands.

Short-term development is desired for oilseed crops having desirable agronomic traits (e. g. mustard, crambe, cardoon, camelina, moringa, Lesquerella and Cuphea). Innovative plant design via accelerated plant domestication programmes is required for a sustainable biomass production; in particular, greater domestication efforts should be directed to perennial species as a renewable feedstock for conversion of fuels. Additional measures needed include lowering the input costs of cultivation, increase in seed oil content with concomitant reduction of seed protein, and increase in protein value. Protein engineering should contribute in optimisation of specific enzymes in oil biosynthesis.

A step-change in the (modest) yield of plant oil per hectare is necessary in order to satisfy the demand from the emerging biodiesel sector. More attention should be paid to oil in leaves of plants. Potentially, microalgae provide such a step-change solution in lipid feedstock supply. Renewable algae diesel has high potential. Knowledge of the metabolism of high oil — producing algae, their processing technology and technical potential deserve further development. Bioengineering microalgae constitutes a promising route to biodiesel production.

Development of advanced biofuels by the chemical industry by increased use of oils and fats as renewable raw materials requires a multidisciplinary effort involving chemists, biologists, biotechnologists, agronomists, plant breeders, chemical engineers, fuel specialists and social scientists. Long-term strategies can be approached by a combination of traditional breeding, genetic engineering (quality and quantity of fatty acids exhibiting a combination of improved fuel properties) and materials science. Biotechnologies are vital in addressing the growing demand for fuel. Thorough working knowledge is required of oil biosynthesis in plants that produce high amounts of industrially important fatty acids in order to elucidate metabolic mechanisms and identify genetic tools for oil production. Detailed characterisation of genomic, proteomic, metabolic, cellular and regulatory aspects of oil production is needed. Application of biotechnology may enhance agronomic traits such as seed yield, oil content, disease resistance, and pod shatter that currently limit wider use of many plants. Further breeding programmes and continued improvement of selected plant germplasm are wanted. Industrial biotechnology (biocatalysis, bioprocessing, fermentation technology, in combination with molecular genetics and metabolic engineering) will revolutionise the production of industrial chemicals from biomass in the 21st century. Sufficient focus on the production of biomass and improved agro-forestry management may cover the global energy provision from biomass.

Available land, potential environmental degradation, habitat destruction, and competition with food production are the major limitations for biofuels. Conflicting demand for vegetable oil commodities between food, bioenergy and chemicals development raises both ethical questions and practical problems, requires critical consideration, and anyhow is currently causing a biodiesel backlash. Technology whereby (scarce) food crops are converted into biofuels has a serious impact on global food supplies and has (partly) caused the high spot market prices. Use of edible feedstock, including palm oil, for biodiesel production is just a transition phase of the industry. Biodiesel focus should change from foodstock to (non-edible) feedstock. Non-food source feedstocks for biodiesel will make foodstocks for biodiesel less needed. However, cultivation of non-food oil crops is not a panacea for biofuels.

It is noticeable that some alternative diesels developed by the petro industry, such as hydrodiesel, are currently based on the same renewable natural lipid feedstocks as biodiesel, thus increasing feedstock rivalry. Increasing prices and environmental consciousness are thus rendering alternatives to conventional fuels even more interesting and pressing. The best sources of biodiesel are waste (waste vegetable oils) and other rotational crops (such as mustard) and non-foodstock oils. In the future, both biodiesel and hydrodiesel could benefit from the availability of highly unsaturated algal oil using (selective) hydrogenation processes. Next-generation biodiesel needs to be feedstock rather than foodstock based.

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