Juan E. Carrasco
A Doctor of Biology, Juan Carrasco is the Head of the Biomass Unit at the CIEMAT Center for Development of Renewable Energies (Spain). He has 30 years’ experience in R&D activity dealing with biomass, particularly in the areas of sustainable biomass production and biomass and biofuels characterization.
He has co-ordinated about forty projects on biomass production and conversion, including the Spanish National Strategic Project for Development and Commercial Demonstration of Energy Crops under Sustainable Conditions, a project developed in 2005 to 2012 with a total budget of EUR 62 million, involving farmers and industry.
He is the coordinator of the European Energy Research Alliance (EERA) Joint Program on Bioenergy, which includes 34 R&D organisations representing 16 European countries.
How important a contribution will bioenergy make to meeting Europe’s 2020 targets?
According to the expectations contained in the National Plans for Renewable Energies, the target is for bioenergy to contribute about 11% of the primary energy consumed in the EU in 2020, or more than 50% of the total primary energy from renewable sources. Furthermore, the share of biofuels by that year should amount to 10%, half of which will come from second generation (2G) biofuels. Additionally, a large part of the expectations to reduce GHG emissions in the EU in the short and long term rely on bioenergy.
In 2012, bioenergy’s contribution was about 8% of the total primary energy consumed in EU countries, which is in line with the planned target. Moreover, in the same year first generation biofuels supplied 4.7% of the transport sector’s needs, representing more than 95% of the target for 2020 for these fuels. However, achieving the goal of biofuels for transport with next generation biofuels is uncertain, since they have not yet reached the commercial stage.
Bioenergy therefore plays a crucial role in meeting Europe´s 2020 targets and in complying with SET-Plan objectives and this will possibly continue to be the case in the coming decades, if the appropriate frameworks and alternatives to exploit its full potential in a sustainable way are adopted.
One of the most controversial aspects of bioenergy has been the competition between land use for energy and for food. How can we ensure sustainability of agriculture for biofuels?
This is quite a tricky subject, in the first place because supplying the world’s population with food depends upon many factors, most of which have a large degree of uncertainty in their definition and projections for the future.
Concerning the potential land available for alternative crops, according to a recent report from the United Nations’ Food and Agriculture Organisation (FAO), more than 2700 million hectares of land not utilised for agriculture are suitable for potential crop production worldwide; and vast areas, including EU agricultural land, are strongly affected by monocultural practises. In the EU, a recent study by the European Environment Agency1 estimates that in 2020 the land surface available for the environmentally sustainable introduction of energy crops, based on resource efficiency criteria, is about 7 Mha, where an annual biomass crop equivalent to 2.3 EJ can be produced. This figure reduces by about 45% the potential for energy crops in a previous study from 20062, but still leaves the energy crop’s potential well above the aggregate waste (including agricultural residues) and forest potentials.
On the other hand, it is worth mentioning that the production of food for the whole world´s population under sustainable conditions up to 2050 does not necessarily imply significant changes in the present agricultural land surface requirements. In fact, there is currently a trend towards the so call 'doubly green' revolution, consisting of increasing crop yields worldwide together with reducing the environmental footprint of agriculture.
Other factors, like the effects of agricultural policies, the actual evolution of the world´s population, the development of the international food and biofuels market or the effects of climate change on agricultural production, will also have a strong influence on the land surface needed for food production in the next decades.
In the above context, and although the results of different studies are controversial, it can be estimated that there is room for the sustainable introduction of energy and, in general, non-food crops into agricultural land, including in the EU. Non-food crops should therefore be seen as an opportunity to create new markets to assure and/or increase farmers’ incomes. A consequence of this is that they contribute to improving the security of food supply, while also encouraging various positive trends, like the diversification of crops and the establishment of new crop rotations in the present monocultural systems, along with the development of low-carbon energy technologies and a reduction in agriculture’s carbon footprint. According to different studies, perennial energy crops may also have additional environmental advantages compared to traditional annual crops, like a reduction in the crop inputs and an increase in soil protection, as well as positive effects on biodiversity, if they are introduced in appropriate conditions.
In any case, the implementation of the new crop systems should be made with prudence and taking into account the local conditions, in order to avoid any significant negative impact. A possible option to effect such a secure introduction is to adopt an integrated view of the new crops in the existing agricultural systems, fixing short term objectives for non-food crops at national or regional levels and making a careful follow up of the integrated systems from the food security, socioeconomic and environmental points of view. Some countries, like the UK, are already adopting this approach and in the US the Environmental Protection Agency fixes annual quotas for biofuels production.
Monitoring the results of the above agrosystems should produce learning curves on its behaviour, thus making it possible to define sustainable conditions, also in economic terms, for their eventual implementation and optimisation.
The development of aquatic crops and waste streams for biofuels production, as land neutral alternatives, as well as of multifuel conversion technologies and of the international biofuels market, are challenges that can contribute to alleviating the competition between food and non-food crops for land use.
Some researchers have concluded that the energy that goes into crop production for fuel far exceeds the energy that the fuel is capable of generating. How sustainable is the use of biomass to produce liquid fuel in reality?
The net energy gains from energy crops and liquid biofuels have been widely debated and are highly variable depending on value chains, local context or the methodological assumptions in the calculations, in particular regarding the handling of co-products.
For feedstock production, however, there exists a wide consensus that the production of raw materials from energy crops used for biofuels production, including agricultural raw materials, present a positive energy balance under the more typical conditions in which those crops are developed. This balance is much more positive for lignocellulosic energy crops, which present energy yield values (specific ratio between the energy contained in the biomass compared to the energy used in the crop production) in the range of 8-15 for average biomass yields under the most common growing conditions.
Considering the entire energy chain, including the energy costs of logistics and the conversion process, the production of first generation biofuels may present a negative energy balance in some particular circumstances (for instance, if grains from low productive areas are used). However, most reviews of these data conclude that current (first generation) biofuels produced in Europe and the USA consume 20% to 70% less fossil energy than their petroleum-based equivalents for a similar distance travelled. These values are even higher for bioethanol produced from sugar cane from high productive areas and with the integration of bagasse for co-generation. Next-generation biofuels are expected to yield even larger savings (70-90%).
One of the focuses of the EERA programme is next generation biofuels. What are the most promising avenues of research in this area?
The generically-titled biomass thermal fuels produced via gasification of biomass, and the bioethanol obtained from the enzymatic hydrolysis and subsequent fermentation of lignocellulosic biomass represent the more advanced routes for the production of 2G biofuels (part of the next generation biofuels), utilising lignocellulosic biomasses. However, important improvements still need to be achieved in order to increase the viability of both pathways, which is the subject of an important research effort. For the gasification-based routes, the ‘flexibilisation’ of biomass fuel requirements, the optimisation of process and gasifier operating conditions and, in particular, the development of viable alternatives for syngas cleaning and syngas upgrading for 2G biofuel production are important research issues.
Regarding the biological pathway, the development of strategies to make the cellulose and hemicellulose more accessible to the action of the hydrolytic enzymes, the genetic improvement of the microbial ability and efficiency to perform the conversion of cellulose and hemicellulose into ethanol, the improvement of the performance and reduction of the costs of hydrolytic enzymes, together with the development of more integrated processes to effect lignocellulose hydrolysis and fermentation are some of most important current R&D activities aimed at making this conversion route more efficient and viable.
Another promising R&D field in bioenergy is the production of synthetic hydrocarbons via thermochemical, biological and/or chemical processes for jet and diesel engine fuel applications, as well as higher alcohols, like buthanol, by biological pathways to improve the performance of the ethanol in fuel mixtures with gasoline.
Hydrothermal gasification and hydropyrolysis are also examples of promising and innovative processes being researched to improve efficiency and reduce the costs of biofuels, as well as the production and use of algae for biofuels (3G) and bioproducts.
In the long term, the EU policy depicts a framework for energy production in 2050 characterized by no public aid, as well as for high efficiency in the use of resources and the implementation of low-carbon and low-environmental-impact technologies. Under the above perspective, it is imperative to find appropriate combinations of raw materials, logistic systems, conversion processes and end fuel uses that comply with the environmental and efficiency policy requirements whilst being economically competitive. The biogas obtained from a mix of different biomass flows, to be used as transport fuel with the integrated production of additional high-value products, is an example of these future processes that needs further research.
For next generation biofuels production, due to the relatively low efficiencies of the conversion processes (50-65%) and with a view to increasing their economic viability, some strategies, including maximising the use of forest and agricultural waste streams involving low-cost and GHG neutral materials and, in particular, the development of the so called biorefineries, are the subject of an intense research and demonstration effort. Biofuels production as part of a biorefinery concept involves the integration of production together with other types of energy and/or other high-value products in order to achieve an efficient utilization of all biomass fractions from an economic point of view. In biorefineries, combinations of raw materials are generally utilised in order to achieve high environmental, economic and efficiency values for the whole process.
In the future context for bioenergy production described, it may occur that the thermal use of biomass and decentralised biomass cogeneration technologies, including micro-cogeneration, could account for a progressively larger share of bioenergy’s contribution at the expense of the generally less efficient technologies for the production of transport biofuels, including next generation biofuels. This means that a considerable research effort will also be required in those areas.
In the above context, the development of ultra-low particle and NOx emission biomass combustion installations adapted to the low heat release and comfort requirements of the houses of the future, and including micro-cogeneration technologies, is a promising area of research. Another promising area to satisfy future heating, cooling and electricity demand in residential, municipal and industrial facilities is the development of intelligent biomass-based small to medium combined heat and power technologies in order to achieve high process efficiency and minimize the carbon footprint.
In addition to developments in conversion technologies, securing biomass supply based on the requirements of conversion plants (and taking into consideration future demand in other emerging markets for biomaterials) is a major issue for the viability of bioenergy and the bioeconomy. The provision of alternatives to maximise the availability of biomass for energy use under sustainable conditions is a priority research avenue which, although it is the subject of a major effort, still requires much more work. There is a limited amount of residue and waste material resources available from biomass, and there are limitations on using the full potential of these resources. As a result, research into sustainable conditions for the production of dedicated non-food crops in EU agricultural and forest land should be a key issue, especially in light of the possible socioeconomic and environmental advantages associated with these crops.
Finally, given the disperse production and low-energy density of in-field biomass, an avenue of major importance in bioenergy RD&D is the development of logistic chains to supply biomass to conversion plants and of model tools to optimise the supply of sustainable biomass to final use sites, taking local conditions into account.
All of the R&D avenues described are being very actively considered in the EERA-Bioenergy Joint Research Program, which is currently a powerful tool for development of bioenergy in the EU.
What is being done to improve the competitiveness of next generation biofuels, and what do you consider to be a realistic time-frame for the commercial use of these fuels?
Some of the most significant research work being done to increase the competitiveness and sustainability of the next generation biofuels has been described in the previous point. This work is the basis for the considerable effort being currently undertaken by the industry, particularly in the USA and in some countries of the EU, to scale up the production of 2G biofuels from different technologies and biomass streams in big pilot and demonstration plants. Forest and agro-industrial waste are most commonly utilized in the pilot and demo projects, but frequently other biomasses, including forest and agricultural residues, energy crops and municipal solid waste (MSW), as well as algae biomass are also being considered in integrated schemes. Many of these projects envisage the production of new fuels with other non-food higher value bioproducts (chemicals, bioplastics, fertilizers…) in biorefineries. As mentioned before, the development of the biorefinery concept is a key issue to increase the competitiveness and sustainability of the next generation biofuels and of the bioeconomy.
In my opinion no full commercial development of next generation biofuels and, in particular, of 2G biofuels, can be expected by the end of this decade. The results obtained in the current demonstration projects will deliver the information required to identify the more competitive alternatives and the real market size and opportunities for the new fuels in the next decade.
The link between transport and fossil fuels seems to be engrained in the public consciousness. What can be done to encourage a societal shift from gasoline to biofuels and how to you evaluate the potential for market uptake?
I think in the last decade public opinion has been very much in favour of a transition from petroleum to agricultural biofuels. But there is an image problem with biofuels, at least in the EU, due to the changing message with regard to the benefits of first generation biofuels. As the results of the various studies in this field become known, there is a loss of credibility for these fuels. The economic crisis has also had a negative impact on public interest in this alternative in many EU countries, given the higher prices of renewable fuels in comparison to fossil fuels.
Clear and consistent messages about the benefits of secure and proven alternatives, the security of use of new products, as well as about the reasonable prices of these alternatives, are key factors to regain public interest in transport biofuels and in low-carbon technologies in general.
The potential market uptake of biofuels is difficult to predict and I think it will rely to a large extent on the policies implemented. The adoption of objectives for liquid biofuel use at the EU level seems to me to be crucial for the development of the market in the short to middle term, but this must be based on a detailed and objective analysis of the real possibilities and alternatives to supply a sustainable future market for these products.
How important has the SET-Plan been in providing a policy framework for the bioenergy sector? What other policy support is needed to ensure that bioenergy achieves its full potential?
The SET-Plan has revealed itself as a crucial initiative in providing an adequate framework for the development of the bioenergy sector. Firstly, by identifying bioenergy as one of the main key areas to support SET-Plan objectives, and then by promoting initiatives to bring together and support complementary R&D programmes (EERA-Bioenergy) and companies (EIBI) in this field. This has strongly contributed to the development of common views in the research and industrial sectors about the needs and priorities for bioenergy, also in view of the global EU situation. Moreover, the implementation of the research Joint Programme in EERA-Bioenergy offers a wide range of possibilities for scientists to exchange knowledge and results, and to share scientific tools and infrastructures in most of the bioenergy research areas, all of which is essential for an efficient use of resources, to increase the scope and quality of the individual results and ultimately to accelerate the development of the bioenergy sector.
The SET-Plan, as well as NER300, Horizon 2020 and ERA Net are also crucial for public Research, Technological Development and Demonstration (RTDD) funding and risk-sharing in the development of advanced bioenergy technologies, flagship projects and innovative industrial implementations in this area.
A stable and predictable framework with appropriate support measures capable of generating private investment, also including the users sector, is a prerequisite for the full development of any new market, and bioenergy is no different. In this context, in the present situation, subjects like ILUC and further sustainability requirements are causing uncertainty over the development potential of the resource. These questions should therefore be clarified and a stable framework for biomass and biofuels production and use should be established in the short term.