Food-based Biofuels Research Articles

Transportation Biofuels in Latvia: A Life Cycle Thinking Approach

Abstract Transport consumes around one-third of Latvia’s final energy demand being the largest sector that produces greenhouse gas emissions. In Latvia, in the year 2019, the share of renewable energy sources in the transport sector was only 4.8 % of the total gross consumption with a target of 7 % of not food-based biofuels by 2030. To tackle climate change problems, one significant task is reducing pollution in the transport sector by substituting fossil with biomass-based fuels. The goal of this study is to develop a methodology for evaluating biofuel production in Latvia considering economic, social, environmental, and technological aspects. A total of 16 specific criteria were selected for biofuel comparison. The methodology is based on a combination of two quantitative approaches, namely Life Cycle Assessment and Multi-Criteria Analysis. The proposed method aims to identify the most sustainable biofuel in Latvia according to a set of specific indicators.

Production and Testing of Butyl and Methyl Esters as New Generation Biodiesels from Fatty Wastes of the Leather Industry

Climate changes caused by the greenhouse effect make it necessary to look for new sources of energy. One of them is waste of a biological origin. They are often difficult to dispose of and such a process can be expensive. Increasingly, they are used to produce biofuels that can replace petroleum-based fuels. They are also an alternative to food-based biofuels. The aim of the work was to propose a method of using fatty waste generated in a plant dealing with tanning animal skins and to evaluate the properties of the produced biofuels. The authors decided to use this waste to produce biodiesel. A patented reactor and technology developed by one of the co-authors was used for this purpose. Two alcohols, butyl and methyl, were used to produce esters in the transesterification process. Animal fats butyl esters (AFBE) and animal fats methyl esters (AFME) have been produced. A high efficiency of the transesterification process was obtained. It amounted to 99.2 (wt.%) for AFME and 98.9 (wt.%) for AFBE. The physicochemical properties of AFBE and AFME biodiesels, diesel fuel, and mixtures of these biodiesels and diesel fuel were tested. Most of the tested properties of AFBE were more favourable than those of AFME. The produced AFBE in relation to AFME was characterized by better cetane number, heat of combustion and calorific value, density, dynamic viscosity, kinematic viscosity, and flash point. For example, the kinematic viscosity for AFBE was 3.6 mm2/s and for AFME 4.1 mm2/s. In contrast, the calorific value of AFBE biodiesel was 39.2 MJ/kg, and that of AFME biodiesel was 38.4 MJ/kg. The use of butanol from the point of view of the properties of the produced biodiesel turned out to be more advantageous in relation to methanol. Due to the fact that the production uses waste fat, the produced biodiesels can be regarded as second-generation biofuels. Producing biodiesel from waste is a way to utilize waste and is beneficial in terms of environmental protection. It can be a way to increase the share of biofuels in the energy balance of regions where large amounts of fat waste products of animal origin are available.

Novel Solutions to Atmospheric Carbon Maintain Advantages of Petroleum

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 196109, “Promising Pathways to Lower Atmospheric Carbon Without Sacrificing the Petroleum Advantage,” by Subodh Chandra Gupta, Cenovus Energy, prepared for the 2019 SPE Annual Technical Conference and Exhibition, Calgary, 30 September-2 October. The paper has not been peer reviewed. The traditional advantages of petroleum-based transport fuels are challenged by the need to lower atmospheric carbon. Despite significant research, development, and investment during the last few decades, humanity still seeks carbon-neutral alternatives to petroleum that can be commercially viable. This paper presents novel approaches to carbon abatement using petroleum that have a strong chance to succeed in fulfilling technological and economic goals. Comparing Renewable Fuel With a Fossil-Fuel/Carbon-Offset Combination Typically, renewable liquid fuels are more expensive than their fossil-fuel counterparts on a unit-energy basis, but they result in lower carbon dioxide (CO2) addition to the atmosphere. Fossil fuels could also be used in such a way that produced CO2 is sequestered at a cost. With carbon-offset costs added to fossil fuel, both can be considered to provide carbon-neutral energy and can be compared on bases of cost and availability. Commodity prices fluctuate because of a variety of factors. Aside from the higher costs of renewables, reading too much into exact crossover points is not useful. Nonetheless, a general statement could be made that, at carbon-abatement costs of approximately $80-100/tonne of CO2, a renewable energy source can compete with fossil fuels. The cited costs of carbon capture and storage also have varied in the range of $100-150/tonne of CO2. The costs depend on emission sources and locations and the technology used for carbon capture. Even at reduced carbon costs, one would still be better off using gasoline - that is, if both commodities (renewable fuels and fossil fuels) were equally available at needed amounts. Technology for food-based bio fuels (e.g., corn-based ethanol) has advanced sufficiently and mostly is used commercially in the US for making bio ethanol for blending with gasoline. However, food-based biofuels compete with the availability of food and result in rising food prices. Data suggest that food-based biofuels are neither cost-competitive nor quantitatively sufficient to supplant fossil fuels. While they can play a role in carbon abatement to an extent if the carbon offset costs rise above $100/tonne of CO2, at present, they do not appear to be the solution to reduce emissions on their own. Can Useful Products Be Monetized From CO2 Conversion? Little other than energy is consumed in proportions greater than 4 billion tonnes/year (e.g., cement). Even if produced CO2 is converted to something that can replace cement, for example, the supply of that substance will be far greater than the amount of cement the world needs and, hence, it will not be able to retain its market - or any - price. If CO2 is converted to other substances, the quantity of products or byproducts will be on the order of 10-plus billion tonnes. This means that no prospective revenues from the useful byproducts can be relied upon, and, thus, it is prudent to only include costs involved in carbon abatement.

Policy feedback and self-reinforcing and self-undermining processes in EU biofuels policy

ABSTRACTThis article traces European Union (EU) biofuels policy development from the late 1990s through to 2015, demonstrating the effects of the early multiple rationales for biofuels in generating both self-reinforcing processes of policy continuity as well as self-undermining processes of policy discontinuity. It argues that features of the EU political and institutional context – most importantly, institutional imperatives for a consensus across multiple EU decision-making bodies and the provision of institutionalised opportunities for policy reviews – are deeply implicated in both self-reinforcing and self-undermining feedback processes. The shift in the balance away from self-reinforcing feedback processes to self-undermining processes after 2009 is explained by the interaction of biofuel interpretive feedbacks with contextual changes, including processes of knowledge accumulation regarding the negative environmental impacts of food-based biofuels.

Sustainable bioenergy production from marginal lands in the US Midwest

Legislation on biofuels production in the USA and Europe is directing food crops towards the production of grain-based ethanol, which can have detrimental consequences for soil carbon sequestration, nitrous oxide emissions, nitrate pollution, biodiversity and human health. An alternative is to grow lignocellulosic (cellulosic) crops on 'marginal' lands. Cellulosic feedstocks can have positive environmental outcomes and could make up a substantial proportion of future energy portfolios. However, the availability of marginal lands for cellulosic feedstock production, and the resulting greenhouse gas (GHG) emissions, remains uncertain. Here we evaluate the potential for marginal lands in ten Midwestern US states to produce sizeable amounts of biomass and concurrently mitigate GHG emissions. In a comparative assessment of six alternative cropping systems over 20 years, we found that successional herbaceous vegetation, once well established, has a direct GHG emissions mitigation capacity that rivals that of purpose-grown crops (-851 ± 46 grams of CO(2) equivalent emissions per square metre per year (gCO(2)e m(-2) yr(-1))). If fertilized, these communities have the capacity to produce about 63 ± 5 gigajoules of ethanol energy per hectare per year. By contrast, an adjacent, no-till corn-soybean-wheat rotation produces on average 41 ± 1 gigajoules of biofuel energy per hectare per year and has a net direct mitigation capacity of -397 ± 32 gCO(2)e m(-2) yr(-1); a continuous corn rotation would probably produce about 62 ± 7 gigajoules of biofuel energy per hectare per year, with 13% less mitigation. We also perform quantitative modelling of successional vegetation on marginal lands in the region at a resolution of 0.4 hectares, constrained by the requirement that each modelled location be within 80 kilometres of a potential biorefinery. Our results suggest that such vegetation could produce about 21 gigalitres of ethanol per year from around 11 million hectares, or approximately 25 per cent of the 2022 target for cellulosic biofuel mandated by the US Energy Independence and Security Act of 2007, with no initial carbon debt nor the indirect land-use costs associated with food-based biofuels. Other regional-scale aspects of biofuel sustainability, such as water quality and biodiversity, await future study.

Biofuel production on the margins

An analysis shows that fuel made from wild, herbaceous vegetation grown on land currently unsuitable for cultivating field crops could contribute substantially to the United States' targets for biofuel production. See Letter p.514 Productive agricultural land that could otherwise be used to produce much-needed food crops is being diverted towards grain-based ethanol production in both Europe and the United States, partly in response to government legislation. An alternative is to grow cellulosic crops on so-called marginal lands. An evaluation of the potential of marginal lands in the Midwestern United States to produce biofuel while mitigating direct greenhouse gas emissions now finds that they have the capacity to produce a significant amount of biofuel energy without the initial carbon debt and indirect land-use costs associated with food-based biofuels.

Microbial Profiles of Rhizosphere and Bulk Soil Microbial Communities of Biofuel Crops Switchgrass (Panicum virgatumL.) and Jatropha (Jatropha curcasL.)

The production of biofuels from the low-input energy crops, switchgrass (Panicum virgatumL.) and jatropha (Jatropha curcasL.), is a sustainable approach that can provide more usable energy and environmental benefits than food-based biofuels. Plant rhizosphere affects the microbial community structure due to variations in root exudation rates and residue chemistry. The objective of this investigation was to determine the profiles of microbial communities associated with rhizosphere and bulk soils of switchgrass or jatropha using phospholipid fatty acid (PLFA) analysis and length heterogeneity PCR (LH-PCR). Switchgrass soil contained a significantly (P<0.05) higher abundance of Gram-positive (i14:0, i15:0, a15:0), Gram-negative (16:1ω5c, 16:1ω7c, 18:1ω5c), and saturated (14:0, 15:0) PLFAs compared to jatropha soil, whereas jatropha had a higher abundance of fungal (18:2ω6, 9c), 18:1ω9c, 20:1ω9c, and 18:0 PLFAs compared to switchgrass soil. Irrespective of plant type, rhizosphere soil contained a significantly (P<0.05) higher abundance of saturated PLFAs (16:0, 18:0, 20:0), actinomycetes (10Me17:0), and fungal (18:2ω6, 9c) PLFAs compared to bulk soil; whereas bulk soil had higher abundance of saturated (14:0), Gram-negative (16:1ω9c, 16:1ω5c, 16:1ω7c), and 18:1ω9c PLFAs compared to rhizosphere soil. Multivariate principle component analysis of PLFAs and LH-PCR percent relative peak areas successfully differentiated the microbial communities of rhizosphere and bulk soils of switchgrass and jatropha.

Optimization of a corn steep medium for production of ethanol from synthesis gas fermentation by Clostridium ragsdalei

Fermentation of biomass derived synthesis gas to ethanol is a sustainable approach that can provide more usable energy and environmental benefits than food-based biofuels. The effects of various medium components on ethanol production by Clostridium ragsdalei utilizing syngas components (CO:CO(2)) were investigated, and corn steep liquor (CSL) was used as an inexpensive nutrient source for ethanol production by C. ragsdalei. Elimination of Mg(2+), NH(4) (+) and PO(4) (3-) decreased ethanol production from 38 to 3.7, 23 and 5.93 mM, respectively. Eliminating Na(+), Ca(2+), and K(+) or increasing Ca(2+), Mg(2+), K(+), NH(4) (+) and PO(4) (3-) concentrations had no effect on ethanol production. However, increased Na(+) concentration (171 mM) inhibited growth and ethanol production. Yeast extract (0.5 g l(-1)) and trace metals were necessary for growth of C. ragsdalei. CSL alone did not support growth and ethanol production. Nutrients limiting in CSL were trace metals, NH(4) (+) and reducing agent (Cys: cysteine sulfide). Supplementation of trace metals, NH(4) (+) and CyS to CSL (20 g l(-1), wet weight basis) yielded better growth and similar ethanol production as compared to control medium. Using 10 g l(-1), the nutritional limitation led to reduced ethanol production. Higher concentrations of CSL (50 and 100 g l(-1)) were inhibitory for cell growth and ethanol production. The CSL could replace yeast extract, vitamins and minerals (excluding NH(4) (+)). The optimized CSL medium produced 120 and 50 mM of ethanol and acetate, respectively. The CSL could provide as an inexpensive source of most of the nutrients required for the syngas fermentation, and thus could improve the economics of ethanol production from biomass derived synthesis gas by C. ragsdalei.

The Ecological Impact of Biofuels

The ecological impact of biofuels is mediated through their effects on land, air, and water. In 2008, about 33.3 million ha were used to produce food-based biofuels and their coproducts. Biofuel production from food crops is expected to increase 170% by 2020. Economic model estimates for land-use change (LUC) associated with food-based biofuels are 67–365 ha 10−6 l−1, leading to increased greenhouse gas emissions for decades compared to business as usual. Biodiversity is reduced by about 60% in U.S. corn and soybean fields and by about 85% in Southeast Asian oil palm plantations compared to unconverted habitat. Consequently, the largest ecological impact of biofuel production may well come from market-mediated LUC. Mitigating this impact requires targeting biofuel production to degraded and abandoned cropland and rangeland; increasing crop yields and livestock production efficiency; use of wastes, residues, and wildlife-friendly crops; and compensatory offsite mitigation for residual direct and indirect impacts.

Land-Use and Alternative Bioenergy Pathways for Waste Biomass

Rapid escalation in biofuels consumption may lead to a trade regime that favors exports of food-based biofuels from tropical developing countries to developed countries. There is growing interest in mitigating the land-use impacts of these potential biofuels exports by converting biorefinery waste streams into cellulosic ethanol, potentially reducing the amount of land needed to meet production goals. This increased land-use efficiency for ethanol production may lower the land-use greenhouse gas emissions of ethanol but would come at the expense of converting the wastes into bioelectricity which may offset fossil fuel-based electricity and could provide a vital source of domestic electricity in developing countries. Here we compare these alternative uses of wastes with respect to environmental and energy security outcomes considering a range of electricity production efficiencies, ethanol yields, land-use scenarios, and energy offset assumptions. For a given amount of waste biomass, we found that using bioelectricity production to offset natural gas achieves 58% greater greenhouse gas reductions than using cellulosic ethanol to offset gasoline but similar emissions when cellulosic ethanol is used to offset the need for more sugar cane ethanol. If bioelectricity offsets low-carbon energy sources such as nuclear power then the liquid fuels pathway is preferred. Exports of cellulosic ethanol may have a small impact on the energy security of importing nations while bioelectricity production may have relatively large impacts on the energy security in developing countries.

Sustainability of food, energy and environment with biofuels.

Abstract Growing reliance on food-based biofuels has created considerable controversy about their impact on food prices and the environment and led to scepticism about their sustainability. This review describes the concept of sustainability in the context of biofuels and then discusses the factors affecting the economic viability of current and next-generation biofuels and their environmental and social sustainability. Cellulosic biofuels from dedicated energy crops offer considerable promise for reducing the competition for land and avoiding many of the negative environmental impacts associated with corn-ethanol. But the production of any type of biofuel is likely to involve trade-offs among the multi-dimensional aspects of sustainability. Technological innovation and policy incentives are needed to develop more sustainable biofuels and to guide the mix of feedstocks, their methods and locations of production.

The Biofuel Controversy

About a decade ago, the main OECD countries decided to promote the use of biofuels so as to reduce greenhouse gases, to contribute to energy self-sufficiency and to create additional demand for agricultural commodities. The introduction of mandatory blending requirements and lavish subsidies spurred fast adoption of this technology. In the course of 2008, the already existing controversy about the effectiveness of this strategy culminated as the resulting upward shift in demand contributed to staggering rises in food prices on world markets. It is uncertain as yet whether this will tone done current ambitions among policy makers to expand biofuel production. The paper shows that high ratios of energy prices to food prices are needed to make biofuel production profitable without the mandatory blending and subsidies. Yet, even if food-based biofuels disappeared, the issue remains that rising high energy prices will promote intensified use worldwide of land for energy crops, requiring huge amounts of mineral fertilizers and putting nature under additional pressure. In policy terms, this defines three major tasks. The first is replacing the current excise taxes on energy carriers by a uniform carbon tax, so as to mitigate greenhouse gas emissions in an efficient manner, the second to prevent price fluctuations on the oil markets from destabilizing food markets, as happened in recent years. Introduction of upper limits on the use of food for biofuel could prove effective here. The third, much wider, task is to make the transition to a partly biomass based energy production possible and sustainable, that is establishing fair distribution of property and user rights over the lands, while safeguarding biodiversity and soil fertility and maintaining adequate labour standards and living conditions, also during periods that these become non-profitable following a drop in energy prices.

Environmental, economic, and energetic costs and benefits of biodiesel and ethanol biofuels

Negative environmental consequences of fossil fuels and concerns about petroleum supplies have spurred the search for renewable transportation biofuels. To be a viable alternative, a biofuel should provide a net energy gain, have environmental benefits, be economically competitive, and be producible in large quantities without reducing food supplies. We use these criteria to evaluate, through life-cycle accounting, ethanol from corn grain and biodiesel from soybeans. Ethanol yields 25% more energy than the energy invested in its production, whereas biodiesel yields 93% more. Compared with ethanol, biodiesel releases just 1.0%, 8.3%, and 13% of the agricultural nitrogen, phosphorus, and pesticide pollutants, respectively, per net energy gain. Relative to the fossil fuels they displace, greenhouse gas emissions are reduced 12% by the production and combustion of ethanol and 41% by biodiesel. Biodiesel also releases less air pollutants per net energy gain than ethanol. These advantages of biodiesel over ethanol come from lower agricultural inputs and more efficient conversion of feedstocks to fuel. Neither biofuel can replace much petroleum without impacting food supplies. Even dedicating all U.S. corn and soybean production to biofuels would meet only 12% of gasoline demand and 6% of diesel demand. Until recent increases in petroleum prices, high production costs made biofuels unprofitable without subsidies. Biodiesel provides sufficient environmental advantages to merit subsidy. Transportation biofuels such as synfuel hydrocarbons or cellulosic ethanol, if produced from low-input biomass grown on agriculturally marginal land or from waste biomass, could provide much greater supplies and environmental benefits than food-based biofuels.