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Production and use of transport biofuels have a history of considerable length. The prototype of the Otto motor, which currently powers gasoline cars, was developed for burning ethanol and sponsored by a sugar factory. The Ford Model T (Tin Lizzy) did run on ethanol. In the early twentieth century, ethanol-fuelled cars were praised because they experienced less wear and tear, were quieter and produced a less smoky exhaust than gasoline-fuelled cars (Dimitri and Effland 2007). Also in the early twentieth century, a significant part of train locomotives in Germany were powered by ethanol (Antoni et al. 2007). In the same country, ethanol from potato starch was used in gasoline as an anti-knocking additive between 1925 and 1945 (Antoni et al. 2007). In the 1930s, ethanol produced from starch or sugar made something of a comeback as road transport fuel in the Midwestern states of the USA, because agricultural prices were very depressed (Solomon et al. 2007). Also in the 1930s, the Brazilian government stimulated gasoline blends with 5% bioethanol. 

Early demonstrations of the diesel motor around 1900 in Paris and St Peters- burg were with a variety of plant- and animal-derived oils. These were thought especially interesting for use in tropical and subtropical countries, where the rela- tively high viscosity of such oils, if compared with fossil diesel, is less of a problem than in colder countries (Knothe 2001). The first patent on making fatty acid esters (biodiesel) was awarded in 1937 and applied in 1938 to powering buses in Belgium (Knothe 2001). During the Second World War, vegetable oils re-emerged as fuels for diesel motors in countries like Brazil, Argentina and China (Knothe 2001). In Japan, soybean oil was used to power ships, pine root oil was used as a high-octane motor fuel and biogenic butanol was used in airplanes (Tsutsui 2003). The Japanese navy conducted extensive research on the production of diesel fuel from coconut oil, birch bark, orange peel and pine needles (Tsutsui 2003). Also, during the Second World War, substitutes for mineral-oil-based gasoline and kerosene were produced in China by the catalytic cracking of vegetable oils (Knothe 2001). Furthermore, thermal destruction of wood was used for producing road transport fuel during the World Wars in Europe (Reed and Lerner 1973). 

The post-World War II re-emergence of transport biofuel use dates from the 1973 hike in petroleum prices, or the ‘first oil crisis’. Tax reductions, subsidies, support for research and development, obligations to fuel providers and artificially high fuel economy ratings for flex fuel cars, which are suitable for high percentages of biofuel in transport fuel, were important government instruments used in this re-emergence (Demirbas ̧ 2007; Szklo et al. 2007; Tyner 2007; Wiesenthal et al. 2008). By now, large sums of money are involved in such support. It has been estimated that in 2006, about US $11 billion was spent on public support measures by the USA, Canada and the European Union (OECD 2008). 

Due to the first oil crisis of 1973, Brazil decided to reduce its dependence on the import of mineral oil by establishing a National Alcohol Program to supply ve- hicles. This program started in 1975, using sugar cane as a feedstock. A second program stimulating the use of ethanol began in the USA in 1978, using mainly corn and to a much lesser extent sorghum as feedstocks (Wheals et al. 1999; Wang et al. 2008a). In the USA, arguments for subsidizing the production of bioethanol since 1978 have included energy security, supporting farm prices and incomes and improvement of air quality (Tyner 2007). Several Canadian provinces started out using 5–10% ethanol–gasoline mixtures in the 1980s (Szklo et al. 2007). The ‘re- discovery’ of biodiesel occurred in the 1980s. Biodiesel initiatives were announced in 1981 in South Africa and in 1982 in Germany, New Zealand and Austria (Kör- bitz 1999). In Europe, substantial production of biodiesel started from about 1987 and in the USA from the 1990s (Knothe 2001). The relatively large production of biofuels in countries such as Germany, France, Italy, Austria and Spain had much to do with an interest in the development of new agricultural markets (Di Lucia and Nilsson 2007). Geopolitical worries about the supply of crude mineral oil and price rises affecting this dominating feedstock for current transport fuels furthered a rapid increase in biofuel production in the twenty-first century, especially after 2004 (Heiman and Solomon 2007). 

The production of conventional mineral oil is likely to peak in the coming decades (GAO 2007; Bentley et al. 2007; Kaufmann and Shiers 2008). An adequate supply thereof may therefore become increasingly expensive and difficult. This has led to calls to – in the words of former US president G. W. Bush – kick the oil ‘ad- diction’ (Bush 2006). Timeliness of a transition to alternative fuels has been stressed (Kaufmann and Shiers 2008). ‘Home-grown’ biofuels, especially, have been argued to be suitable for energy security (Tyner 2007). There is also much concern about the pollution originating in the burning of fossil fuels. Recently, the effects thereof on climate have become important on the international political agenda. This, in turn, has led to increasing calls to reduce the emission of greenhouse gases, such as CO2. Such calls extend to transportation because worldwide transport accounts for about 22% of the total use of primary energy and is overwhelmingly mineral oil based (de la Rue du Can and Price 2008). For instance, regarding the USA, min- eral oil accounted in 2006 for about 97.8% of total transport energy use (Heiman 

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and Solomon 2007). Worldwide, the consumption of petroleum products represents 94% of energy use in the transportation sector (de la Rue du Can and Price 2008), whereas in 2004, about 60% of all mineral oil was used for transportation (Quadrelli and Peterson 2007). Proponents of biofuels have argued that replacement of mineral oil by biofuels is a good way to reduce greenhouse gas emissions. 

It has furthermore been stated that the potential for replacing fossil transport fuels with biofuels is very substantial indeed. de Vries et al. (2007) have suggested that by 2050, up to 300 EJ (= 300 × 1018 J) of liquid biofuels may be produced worldwide. An even higher estimate for liquid biofuel production by 2050 (455 EJ) has been proposed by Moreira (2006). Such amounts can in all probability cover demand for transport fuels in 2050, as the 2007 primary energy consumption for transport amounted to about 100 EJ (de la Rue du Can and Price 2008). Use of transport fuels by means of transport (‘end use’) was probably in the 85–90 EJ range, with the remaining amount used for winning, refining and distribution (Colella et al. 2005; EUCAR et al. 2007; Winebrake et al. 2007). The potential importance of biofuels in replacing fossil transport fuels is by now much stressed by the Brazilian government. In Brazil, ethanol from sugar cane is currently a substantial transport biofuel. In 2004, its share in energy for road transport was near 14% and in 2007 about 20% (OECD 2008). In 2006, 70% of the new cars sold in Brazil were ‘flex cars’, able to run on either 100% ethanol or a fossil fuel–ethanol blend (Quadrelli and Peterson 2007). The claims about the benefits and potential of transport biofuels have, however, been contested. And the resulting debate has been much fuelled by the high food prices in 2008, which have been partially linked to increasing transport biofuel production (OECD-FAO 2007). 

This book will give a seed-to-wheel perspective on biofuels for road transport and will deal with a number of environmental issues that have emerged in the current biofuel debate. This first chapter is introductory and structured as follows: firstly, Sects. 1.2–1.6 will deal with the physical basis and the variety of biofuels and the ways to produce and apply them in transport. Secondly, in Sect. 1.7, developments in production volume, costs and prices will be discussed. Thereafter, in Sect. 1.8, the debate on the pros and cons of transport biofuels that has emerged will be briefly surveyed, and the rest of the book will be outlined. 

Energy security, high atmospheric greenhouse gas levels, and issues associated with fossil fuel extraction are among the incentives for developing alternative and renewable energy resources. Biofuels, produced from a wide range of feedstocks, have the potential to reduce greenhouse gas emissions. In particular, the use of microalgae as a feedstock has received a high level of interest in recent years. 

Microalgal biofuels are promising replacement for fossil fuels and have the potential to displace petroleum-based fuels while decrease greenhouse gas emissions. The primary focus of research and development toward algal biofuels has been on the production of biodiesel or renewable diesel from the lipid fraction, with use of the non-lipid biomass fraction for production of biogas, electricity, animal feed, or fertilizer. 

Since the non-lipid fraction, consisting of mainly carbohydrates and proteins, comprises approximately half of the algal biomass, our approach is biological conversion of the lipid-extracted algal biomass (LEAB) into fuels. We used LEAB from Nannochloropsis salina, and ethanol was the model product. The first step in conversion of LEAB to ethanol was deconstruction of the cell wall into fermentable substrates by using different acids or enzymes. Sugar release yields and rates were compared for different treatments. One-step sulfuric acid hydrolysis had the highest yield of released sugars, while the one-step hydrochloric acid treatment had the highest sugar release rate. Enzymatic hydrolysis produced acceptable sugar release rates and yields but enzymes designed for algal biomass deconstruction are still needed. Proteins were deconstructed using a commercially available protease. 

The hydrolysate, containing the released sugars, peptides, and amino acids, was used as a fermentation medium with no added nutrients. Three ethanologenic microorganisms were used for fermentation: two strains of Saccharomyces cerevisiae (JAY270 and ATCC 26603) and Zymomonas mobilis ATCC 10988. Ethanol yields and productivities were compared. Among the studied microorganisms, JAY270 had the highest ethanol yield while Z. mobilis had the lowest yield for most of the studied conditions. A protease treatment improved the biomass and ethanol yields of JAY270 by providing more carbon and nitrogen. 

To increase ethanol productivity, a continuous fermentation approach was adapted. Continuous stirred tank reactors have increased productivity over batch systems due to lower idle time. The downtime associated with batch fermentation is the time it takes for empting, cleaning, and filling the reactor. Productivity in the continuous fermentation was limited by the growth characteristics of the microorganism since at high flow rates, with washout occurring below a critical residence time. To overcome the washout problem, the use of an immobilized cell reactor was explored. The performance (ethanol productivity) of free and immobilized cells was compared using an enzymatic hydrolysate of LEAB. Higher ethanol productivities were observed for the continuous immobilized cell reactor compared to the stirred tank reactor. 

Seaweed cultivation is a high growth industry that is primarily targeted at human food and hydrocolloid markets. However, seaweed biomass also offers a feedstock for the production of nutrient-rich biochar for soil amelioration. We provide the first data of biochar yield and characteristics from intensively cultivated seaweeds (Saccharina, Undaria and Sargassum – brown seaweeds, and Gracilaria, Kappaphycus and Eucheuma – red seaweeds). While there is some variability in biochar properties as a function of the origin of seaweed, there are several defining and consistent characteristics of seaweed biochar, in particular a relatively low C content and surface area but high yield, essential trace elements (N, P and K) and exchangeable cations (particularly K). The pH of seaweed biochar ranges from neutral (7) to alkaline (11), allowing for broad-spectrum applications in diverse soil types. We find that seaweed biochar is a unique material for soil amelioration that is consistently different to biochar derived from ligno-cellulosic feedstock. Blending of seaweed and ligno-cellulosic biochar could provide a soil ameliorant that combines a high fixed C content with a mineral-rich substrate to enhance crop productivity. 

This practical manual "Better management practices for seaweed farming" is produced by the Philippines national team under the ASEAN Foundation supported project "Strengthening capacity of small holder ASEAN aquaculture farmers for competitive and sustainable aquaculture" implemented by NACA in five ASEAN countries. The long-term objective of the project was to assist ASEAN small- scale aquaculture farmers improve their livelihoods by being competitive in markets and improving farm management practices to deliver quality and sustainably produced aquaculture products.