Bioenergy Plants Research Articles

Growth performance of Calophyllum inophyllum at a bioenergy trial plot in Bukit Soeharto Research and Education Forest, East Kalimantan

The Indonesian government has committed to providing its entire population with energy through the National Energy Policy, which highlights the importance of diversification, environmental sustainability, and enhanced deployment of domestic energy resources. The contribution of new and renewable energy (NRE) to the nation’s energy supply is mandated to reach 23% by 2025, with bioenergy an important NRE alternative. If developed and deployed appropriately, bioenergy plantations have potential to restore degraded land and enhance biodiversity and environmental services while supporting rural livelihoods. As a potential biofuel tree species suited to the tropics, Calophyllum inophyllum (nyamplung) is being tested across wide-ranging degraded forest conditions in Indonesia. Nyamplung is a potential biodiesel alternative as it grows well in harsh environmental conditions, produces non-edible seed oil, has high amounts of kernel oil and fruits profusely. Here we report growth performance in a plantation trial plot established in February 2018, on previously burned land in Mulawarman University’s Bukit Soeharto Research and Educational Forest. Growth of this two-year-old plantation is strong compared to other Indonesian sites, with average survival rate above 90% on Ultisol soil, which is classified as low fertility and acidic. The findings reveal that different doses of fertilizer applications and slope gradient have no significant effects on growth performance. In addition, trees have already started to flower and fruit, and are colonized by bird species and insects, including bees and butterflies. The study indicates that nyamplung adapts well to different land and soil types. Bioenergy plantations on degraded land are a promising approach for land restoration, and enhance native biodiversity and environmental services while providing a source of renewable energy.

Modeling the ecosystem service of agricultural residues provision for bioenergy production: A potential application in the Emilia-Romagna region (Italy)

Agro-ecosystems have large potentials for supporting human well-being and local development, also by providing large amounts of organic matter for bioenergy generation. The use of agricultural residues was proposed as a possible solution to support energy transition, while avoiding conflicts for the use of agricultural land destined to food production.The present work uses an Ecosystem Services (ES) approach to map and estimate the potential availability of agricultural residues (potential ES supply) in the Emilia-Romagna region (Italy), where high productive croplands are present. The map was overlapped with the bioenergy plants currently present in the region (ES demand) that could be sustained by residues, considering a buffer area of 10 km radius for a sustainable supply chain and under the assumption of using only the 25% of total residues. Additionally, suitable areas for bioenergy development were mapped by means of a hotspot analysis.The results showed that the Emilia-Romagna region has a large availability of agricultural residues to be potentially used for bioenergy generation. The 82.4% of the total installed power of biogas plants and the whole installed power of those using woody biomasses may be supported by using agricultural residues. When considering buffer areas for sustainable supply chains, agricultural residues could meet the 95% and 50% of total demand from biogas and solid biomasses plants, respectively. However, competition for agricultural residues among bioenergy plants could arise because of the overlap of their buffer zones. Moreover, hotspot analysis revealed large suitable areas for the development of environmental and cost-effective biogas plants.Contrasting ES supply and demand may unveil unexplored forms of sustainable development in agro-ecosystems, thus contributing to a more rational use of agricultural production which supports renewable energies without competing for the agricultural land.

Morphological Characteristics of Sugar Palm [Arenga Pinnata Merr.] Seedling Growth Based on Cotyledon Petiole Position

Sugar palm is a bioenergy plant with great potential in food security, biopolymers, biofuel, and herbal medicine. Sugar palm seed germination is indicated by the appearance of cotyledon petiole, where there are several different positions. Morphological characteristics of sugar palm seeds at various positions of cotyledon petiole are not currently available. This research aimed to study the morphology characters of sugar palm seedlings with different cotyledon petiole positions. The research applied Experiment in Completely Random Design with four treatments, each repeated three times. The four treatments are the cotyledon petiole position, namely P1: cotyledon petiole in right-center, P2: cotyledon petiole in left-center, P3: cotyledon petiole in left-bottom, and P4: cotyledon petiole in right-bottom. The results showed that morphologically, there was no significant difference in the sugar palm seedling growth with each cotyledon petiole position [256 DAS]. Range of seed height 47,63-57,50 cm, range number of leaf midribs 2-3,33, range of primary root length 13,73-21,76 cm and, range of secondary root length 28,60-44,26 cm.

Isoprene and monoterpene emissions from alder, aspen and spruce short-rotation forest plantations in the United Kingdom

Abstract. An expansion of bioenergy has been proposed to help reduce fossil-fuel greenhouse gas emissions, and short-rotation forestry (SRF) can contribute to this expansion. However, SRF plantations could also be sources of biogenic volatile organic compound (BVOC) emissions, which can impact atmospheric air quality. In this study, emissions of isoprene and 11 monoterpenes from the branches and forest floor of hybrid aspen, Italian alder and Sitka spruce stands in an SRF field trial in central Scotland were measured during two years (2018–2019) and used to derive emission potentials for different seasons. Sitka spruce was included as a comparison as it is the most extensive plantation species in the UK. Winter and spring emissions of isoprene and monoterpenes were small compared to those in summer. Sitka spruce had a standardised mean emission rate of 15 µgCg-1h-1 for isoprene in the dry and warm summer of 2018 – more than double the emissions in 2019. However, standardised mean isoprene emissions from hybrid aspen were similar across both years, approximately 23 µgCg-1h-1, and standardised mean isoprene emissions from Italian alder were very low. Mean standardised total monoterpene emissions for these species followed a similar pattern of higher standardised emissions in the warmer year: Sitka spruce emitting 4.5 and 2.3 µgCg-1h-1 for 2018 and 2019, aspen emitting 0.3 and 0.09 µgCg-1h-1, and Italian alder emitting 1.5 and 0.2 µgCg-1h-1, respectively. In contrast to these foliage emissions, the forest floor was only a small source of monoterpenes, typically 1 or 2 orders of magnitude lower than foliage emissions on a unit of ground area basis. Estimates of total annual emissions from each plantation type per hectare were derived using the MEGAN 2.1 model. The modelled total BVOC (isoprene and monoterpenes) emissions of SRF hybrid aspen plantations were approximately half those of Sitka spruce for plantations of the same age. Italian alder SRF emissions were 20 times smaller than from Sitka spruce. The expansion of bioenergy plantations to 0.7 Mha has been suggested for the UK to help achieve net-zero greenhouse gas emissions by 2050. The model estimates show that, with such an expansion, total UK BVOC emissions would increase between <1 % and 35 %, depending on the tree species planted. Whereas increases might be small on a national scale, regional increases might have a larger impact on local air quality.

The effects of cultivar and rotation length (5 vs. 10 years) on biomass production and sustainability of poplar (Populus spp.) bioenergy plantation

AbstractPoplars (Populus spp.) managed in short rotation woody crop (SRWC) systems are considered very promising in terms of biomass production for energy purposes in a temperate zone. In this study, several gaps in knowledge regarding the selection of the plant material, cultivar‐specific responses to coppicing and rotation length are addressed. Five‐ and 10‐year rotation lengths were considered, with a focus on the sustainability of the plantation and the quantification of the biomass production of 10 commercially available hybrid poplar cultivars during two consecutive 5‐year rotation cycles versus one 10‐year rotation in northern Poland. The biomass production varied considerably among cultivars, ranging from 1.6 (‘AF8’) to 7.5 (‘NE42’) Mg ha−1 year−1 at the end of the first 5‐year rotation, and 0.0 (‘AF8’)–5.4 (‘Degrosso’) Mg ha−1 year−1 in the second 5‐year rotation, while in a single 10‐year rotation, the mean annual increment (MAI) ranged from 1.0 (‘AF8’) to 15.1 (‘NE42’) Mg ha−1 yr−1. The 5‐year rotation cycles negatively influenced the sustainability of the plantation due to the high mortality of stems and sprouts in the second 5‐year coppice rotation. In the case of 5‐year and longer rotations, replanting (not resprouting) after harvest may be a more advantageous practice for maximizing the regeneration. The 10‐year rotation cycle allowed for enough development of the crown and root systems to produce sufficient basal area and height to achieve maximal MAI in the trees. The study revealed that an age ≥10 is a biologically optimal rotation age as the slope of MAI was equal/close to zero. This study further showed the crucial importance of testing cultivars before introducing them on a commercial scale and provided valuable information on poplar cultivars available to stakeholders in the biomass market.

Global scenarios of irrigation water abstractions for bioenergy production: a systematic review

Abstract. Many scenarios of future climate evolution and its anthropogenic drivers include considerable amounts of bioenergy as a fuel source, as a negative emission technology, and for providing electricity. The associated freshwater abstractions for irrigation of dedicated biomass plantations might be substantial and therefore potentially increase water limitation and stress in affected regions; however, assumptions and quantities of water use provided in the literature vary strongly. This paper reviews existing global assessments of freshwater abstractions for bioenergy production and puts these estimates into the context of scenarios of other water-use sectors. We scanned the available literature and (out of 430 initial hits) found 16 publications (some of which include several bioenergy-water-use scenarios) with reported values on global irrigation water abstractions for biomass plantations, suggesting water withdrawals in the range of 128.4 to 9000 km3 yr−1, which would come on top of (or compete with) agricultural, industrial, and domestic water withdrawals. To provide an understanding of the origins of this large range, we present the diverse underlying assumptions, discuss major study differences, and calculate an inverse water-use efficiency (iwue), which facilitates comparison of the required freshwater amounts per produced biomass harvest. We conclude that due to the potentially high water demands and the tradeoffs that might go along with them, bioenergy should be an integral part of global assessments of freshwater demand and use. For interpreting and comparing reported estimates of possible future bioenergy water abstractions, full disclosure of parameters and assumptions is crucial. A minimum set should include the complete water balances of bioenergy production systems (including partitioning of blue and green water), bioenergy crop species and associated water-use efficiencies, rainfed and irrigated bioenergy plantation locations (including total area and meteorological conditions), and total biomass harvest amounts. In the future, a model intercomparison project with standardized parameters and scenarios would be helpful.

Analysis of Promotion Policies for the Valorization of Food Waste from Industrial Sources in Taiwan

Growing concern about circular bioeconomy and sustainable development goals (SDGs) for the valorization of food waste has raised public awareness since 2015. Therefore, the present study focused on the promotion policies and regulatory measures for the valorization of mandatory recyclable food waste from industrial sources in Taiwan, including the animal/plant production farms and food-processing plants. According to the official data on the annual statistics during the period of 2015–2019, it showed that the food waste from alcoholic beverage manufacturers (i.e., lees, dregs, or alcohol mash) and oyster farms (i.e., waste oyster shell) accounted for about half (about 250,000 metric ton) of industrial food waste generation in Taiwan. In order to effectively reduce the burdens on incinerators/landfills and their environmental impacts, the central governing agencies jointly promulgated some regulatory measures for promoting the production of biobased products from the industrial food waste valorization like animal feed, soil fertilizer, and bioenergy. These relevant acts include the Waste Management Act, the Fertilizer Management Act, the Feed Management Act, and the Renewable Energy Development Act. In addition, an official plan for building the food waste bioenergy plants at local governments via anaerobic digestion process, which was estimated to be completed by 2024, was addressed as a case study to discuss their environmental and economic benefits.

Genomewide comparative analysis of codon usage bias in three sequenced Jatropha curcas

Jatropha curcas has recently emerged as an important bioenergy plant which is an ideal alternative for fossil fuels. It is particularly significant to analyse the codon usage bias (CUB) and further evaluate the intraspecific genetic divergence of three J. curcas in Asia, considering its potential economic benefits and various utilities. In the present study, the patterns of CUB were systematically compared, and the factors shaping CUB were identified in all three genomes of J. curcas. Our observations indicate that the preference for A/T nucleotides and A/T ending codons was present in all the three genomes. Moreover, 11 identical high-frequency codons as well as the optimal expression receptor Nicotiana tabacum were confirmed. Besides, it was observed that CUB resulted from the combined effects of natural selection and mutation pressure, while the natural selection was the determining factor. Eventually, similarity indices based on relative synonymous codon usage (RSCU) values implied low intraspecific genetic divergence in three Asian J. curcas. This study provides useful clues for improving the expression level of exogenous genes and optimizing breeding programmes by molecular-assisted breeding in J. curcas.

A scalable and spatiotemporally resolved agricultural life cycle assessment of California almonds

PurposeCalifornia’s Central Valley produces more than 75% of global commercial almond supply, making the life cycle performance of almond production in California of global interest. This article describes the life cycle assessment of California almond production using a Scalable, Process-based, Agronomically Responsive Cropping System Life Cycle Assessment (SPARCS-LCA) model that includes crop responses to orchard management and modeling of California’s water supply and biomass energy infrastructure.MethodsA spatially and temporally resolved LCA model was developed to reflect the regional climate, resource, and agronomic conditions across California’s Central Valley by hydrologic subregion (San Joaquin Valley, Sacramento Valley, and Tulare Lake regions). The model couples a LCA framework with region-specific data, including water supply infrastructure and economics, crop productivity response models, and dynamic co-product markets, to characterize the environmental performance of California almonds. Previous LCAs of California almond found that irrigation and management of co-products were most influential in determining life cycle CO2eq emissions and energy intensity of California almond production, and both have experienced extensive changes since previous studies due to drought and changing regulatory conditions, making them a focus of sensitivity and scenario analysis.Results and discussionResults using economic allocation show that 1 kg of hulled, brown-skin almond kernel at post-harvest facility gate causes 1.92 kg CO2eq (GWP100), 50.9 MJ energy use, and 4820 L freshwater use, with regional ranges of 2.0–2.69 kg CO2eq, 42.7–59.4 MJ, and 4540–5150 L, respectively. With a substitution approach for co-product allocation, 1 kg almond kernel results in 1.23 kg CO2eq, 18.05 MJ energy use, and 4804 L freshwater use, with regional ranges of 0.51–1.95 kg CO2eq, 3.68–36.5 MJ, and 4521–5140 L, respectively. Almond freshwater use is comparable with other nut crops in California and globally. Results showed significant variability across subregions. While the San Joaquin Valley performed best in most impact categories, the Tulare Lake region produced the lowest eutrophication impacts.ConclusionWhile CO2eq and energy intensity of almond production increased over previous estimates, so too did credits to the system for displacement of dairy feed. These changes result from a more comprehensive model scope and improved assumptions, as well as drought-related increases in groundwater depth and associated energy demand, and decreased utilization of biomass residues for energy recovery due to closure of bioenergy plants in California. The variation among different impact categories between subregions and over time highlight the need for spatially and temporally resolved agricultural LCA.

Economic perspective of ethanol and biodiesel coproduction from industrial hemp

In this study, the economics of producing biofuels from an industrial hemp (Cannabis sativa) genotype – 19m96136 was investigated. A lignocellulosic biofuel plant, hourly consuming 85 metric tons of hemp biomass was modeled in SuperPro Designer®. The integrated bioenergy plant produced hemp biodiesel and bioethanol from lipids and carbohydrates, respectively. The structural composition of the industrial hemp plant was analyzed in a previous study. The data obtained was used to simulate feedstock composition in SuperPro Designer®.The simulation results indicated that Hemp containing 2% lipids can yield up to 3.95 million gallons of biodiesel annually. On improving biomass lipid content to 5 and 10%, biodiesel production increased to 9.88 and 19.91 million gallons, respectively. The breakeven unit production cost of hemp biodiesel with 2, 5, and 10% lipid containing hemp was $18.49, $7.87, and $4.13/gallon, respectively. The biodiesel unit production cost when utilizing 10% lipid-containing hemp was comparable to soybean biodiesel at $4.13/gallon. Furthermore, sensitivity analysis revealed the possibility of a 7.80% reduction in unit production cost upon a 10% reduction in hemp feedstock cost. Furthermore, industrial hemp was capable of producing between 307.80 and 325.82 gallons of total biofuels per hectare of agricultural land than soybean.

The influence of perennial bioenergy crops on the soil fertility restoration

It was found that long-term cultivation of perennial cereal bioenergy plants has a positive effect on the fertility of low-yielding soils. Thus, for the cultivation of switchgrass for nine years, the content of organic carbon in the soil increased from 1.87 to 2.40%, and for the cultivation of giant miscanthus for six years from 1.87 to 2.42%. Conclusions. Laying plantations of perennial cereal bioenergy plants on low-yielding and erosion-prone lands helps to restore their fertility and provides a sustainable supply of high quality feedstock for the production of biofuels.

Agricultural and environmental aspects of sustainable bioenergy development

Purpose.The analysis of the agroecological state of agricultural lands of Ukraine and the factors that cause soil degradation are given in the article. Conclusions. Large-scale use of straw for energy may be one of the key factors in reducing organic carbon in the soil. This will activate the processes of humus mineralization. Therefore, the use of straw for energy production does not meet the criteria of sustainable development and violates Ukrainian legislation on land use. The sustainable bioenergy development must be based on the biomass of high-productive bioenergy plants, which should be grown on low-yielding and degraded (marginal) land.

Technological bases of creation of industrial plantations of high-yield bioenergy crops

Purpose. To develop technological bases of creation of industrial plantations on the basis of highly productive bioenergy crops, their cultivation, harvesting and supply of biomass for ensuring uninterrupted operation of heat-generating equipment in solid fuel boilers throughout the heating season. Research methods. In the research process, we have used the common scientific methods: the system analysis of trends in bioenergy development in Ukraine; series of dynamics of creation of production plantations of bioenergy plants; expert estimates of actual biofuel production; computer processing of acreage sizes, yields and gross harvest of bio-raw materials; forecasting of biofuel production and development of logistical base. Results. Тhe productivity of perennial bioenergy crops has been investigated. The technological basis for the creation of industrial plantations has been developed. Effective methods for collecting and supplying biomass for uninterrupted operation of heat generating equipment in solid fuel boilers throughout the heating season are substantiated. Сonclusions. To create an efficient scheme of thermal energy production under the conditions of the Forest-Steppe of Ukraine it is necessary to organize a planned supply of fuel chips and to develop an individual scheme of the energy conveyor to provide the heating season with raw materials based on the required amount of biomass on average: energy willow and poplar 14 t/ha; miscanthus and swichgrass 20 t/ha.

A Model to Assess Eastern Cottonwood Water Flow Using Adjusted Vapor Pressure Deficit Associated with a Climate Change Impact Application

Short-rotation woody crops have maintained global prominence as biomass feedstocks for bioenergy, in part due to their fast growth and coppicing ability. However, the water usage efficiency of some woody biomass crops suggests potential adverse hydrological impacts. Monitoring tree water use in large-scale plantations would be very time-consuming and cost-prohibitive because it would typically require the installation and maintenance of sap flux sensors and dataloggers or other instruments. We developed a model to estimate the sap flux of eastern cottonwood (Populus deltoides. Bartr. ex Marsh.)) grown in bioenergy plantations. This model is based on adjusted vapor pressure deficit (VPD) using Structural Thinking and Experiential Learning Laboratory with Animation (STELLA) software (Architect Version 1.8.2), and is validated using the sap flux data collected from a 4-year-old eastern cottonwood biomass production plantation. With R2 values greater than 0.79 and Nash Sutcliffe coefficients greater than 0.69 and p values < 0.001, a strong agreement was obtained between measured and predicted diurnal sap flux patterns and annual sap flux cycles. We further validated the model using eastern cottonwood sap flux data from Aiken, South Carolina, USA with a good agreement between method predictions and field measurements. The model was able to predict a typical diurnal pattern, with sap flux density increasing during the day and decreasing at night for a 5-year-old cottonwood plantation. We found that a 10% increase in VPD due to climate change increased the sap flux of eastern cottonwood by about 5%. Our model also forecasted annual sap flux characteristics of measured cycles that increased in the spring, reached a maximum in the summer, and decreased in the fall. The model developed here can be adapted to estimate sap flux of other trees species in a time- and cost-effective manner.

ASSESSMENT OF BIOMASS UTILIZATION FOR ENERGY PRODUCTION FROM AGRICULTURAL RESIDUE

This paper discusses biomass potential utilization for energy production from primary and secondary agriculture residue assessment. The purpose of the paper – to carry out an assessment of the biomass utilization potential from agricultural residue. The research methodology based on analyzing statistical data of Lithuania, to estimate the biomass utilization possibilities from agriculture residue. The research methods involve the methodology for the assessment using the mathematics equations and also based on methods of analysis, synthesis, and others to achieve to solve the problem of competition between the food industry and agriculture sectors for the food gap in the near future. The authors determined that the potential energy yield from primary agriculture residue is higher than secondary agriculture residue, and primary residue utilization for energy production is more useful than secondary residue. The problem with these results discloses that secondary agriculture residue utilization for bioenergy production needs more support with the development of knowledge and skills in Lithuania, especially should apply to attention to researches of non-traditional bioenergy plants. The results of the paper will be useful for further research in energy and agricultural development.  

Biological Parts for Plant Biodesign to Enhance Land-Based Carbon Dioxide Removal.

A grand challenge facing society is climate change caused mainly by rising CO2 concentration in Earth's atmosphere. Terrestrial plants are linchpins in global carbon cycling, with a unique capability of capturing CO2 via photosynthesis and translocating captured carbon to stems, roots, and soils for long-term storage. However, many researchers postulate that existing land plants cannot meet the ambitious requirement for CO2 removal to mitigate climate change in the future due to low photosynthetic efficiency, limited carbon allocation for long-term storage, and low suitability for the bioeconomy. To address these limitations, there is an urgent need for genetic improvement of existing plants or construction of novel plant systems through biosystems design (or biodesign). Here, we summarize validated biological parts (e.g., protein-encoding genes and noncoding RNAs) for biological engineering of carbon dioxide removal (CDR) traits in terrestrial plants to accelerate land-based decarbonization in bioenergy plantations and agricultural settings and promote a vibrant bioeconomy. Specifically, we first summarize the framework of plant-based CDR (e.g., CO2 capture, translocation, storage, and conversion to value-added products). Then, we highlight some representative biological parts, with experimental evidence, in this framework. Finally, we discuss challenges and strategies for the identification and curation of biological parts for CDR engineering in plants.

Assessment of Molecular Diversity in Biofuel Crops.

Sustainable biofuel sources require the new sources of biofuel crops that can be developed into scalable plantation to meet the growing energy demands. Diverse supply sources of bioenergy plantations (edible, nonedible, and perennial grasses) will enable de-risking impact on geography and climate change that humans are likely to face in future. Use of phenotypic descriptors alone does not provide a deep insight into plantation population dynamics and molecular diversity of a biofuel crop. We provide protocols and methods to rapidly assess population parameters for emerging biofuel crops using genomics. This article has an application focus on next-generation sequencing to assess biofuel crop diversity. Use of these methods can accelerate germplasm assessment to accelerate population development and creation of sustainable biofuel plantations.

Nutrient (N, P, K) use efficiency and nitrogen balance in a bioenergy plantation of Populus deltoides clone Lux in San Piero A Grado (Pisa), Italy

Energy crops have proved to be a viable alternative to fossil fuels. However, high biomass production always means that large quantities of nutrients from the soil are removed at harvest. The goal of this work was to estimate nutrient (nitrogen, phosphorous, potassium) use efficiency (NUE) and nitrogen balance in an eight-year-old Populus deltoides clone Lux, short rotation forestry under two cutting cycles, every two (biennial) and three (triennial) years, carried out under Mediterranean climate conditions. Results indicate that NUE, for all the analyzed elements, contained variations with slightly higher values for nitrogen and phosphorous in the triennial cycle. Although poplar cultivation has a positive nutrient efficiency, in terms of nitrogen, there is significant loss of this element in the crop cycle.

Assessment of carbon dioxide removal potentialviaBECCS in a carbon-neutral Europe

The European technical potential for biogenic carbon dioxide removal is assessed considering seven different BECCS configurations that do not require purpose-grown bio-energy plantations.

Calculation of the power of thermal energy consumed for heating the reactor of a bioenergy plant

The issues of calculating the power of thermal energy consumed for heating biomass in the reactor of a bioenergy plant are considered. Based on the Fourier heat equation, a solution for the axisymmetric cylindrical problem under boundary conditions of the first kind is obtained, and the power of additional heat sources in a cylindrical biogas reactor is calculated. The influence of the height of the bioreactor and the temperature difference of the biomass on the power consumption of an additional source of thermal energy is analyzed