Sustainable production of algae will depend on understanding trade-offs at the energy-water nexus. Algal biofuels promise to improve the environmental sustainability profile of renewable energy along most dimensions. In this assessment of potential US freshwater production, we assumed sustainable production along the carbon dimension by simulating placement of open ponds away from high-carbon-stock lands (forest, grassland, and wetland) and near sources of waste CO 2 . Along the water dimension, we quantified trade-offs between water scarcity and production for an ‘upstream’ indicator (measuring minimum water supply) and a ‘downstream’ indicator (measuring impacts on rivers). For the upstream indicator, we developed a visualization tool to evaluate algae production for different thresholds for water surplus. We hypothesized that maintaining a minimum seasonal water surplus would also protect river habitat for aquatic biota. Our study confirmed that ensuring surplus water also reduced the duration of low-flow events, but only above a threshold. We also observed a trade-off between algal production and the duration of low-flow events in streams. These results can help to guide the choice of basin-specific sustainability targets to avoid conflicts with competing water users at this energy-water nexus. Where conflicts emerge, alternative water sources or enclosed photobioreactors may be needed for algae cultivation.
Link to the website with documentation and download instructions for the PNNL Global Change Assessment Model (GCAM), a community model or long-term, global energy, agriculture, land use, and emissions. BioEnergy production, transformation, and use is an integral part of GCAM modeling and scenarios.
The paper describes an approach to landscape design that focuses on integrating bioenergy production with other components of environmental, social and economic systems. Landscape design as used here refers to a spatially explicit, collaborative plan for management of landscapes and supply chains. Landscape design can involve multiple scales and build on existing practices to reduce costs or enhance services. Appropriately applied to a specific context, landscape design can help people assess trade-offs when making choices about locations, types of feedstock, transport, refining and distribution of bioenergy products and services. The approach includes performance monitoring and reporting along the bioenergy supply chain. Examples of landscape design applied to bioenergy production systems are presented. Barriers to implementation of landscape design include high costs, the need to consider diverse land-management objectives from a wide array of stakeholders, up-front planning requirements, and the complexity and level of effort needed for successful stakeholder involvement. A landscape design process may be stymied by insufficient data or participation. An impetus for coordination is critical, and incentives may be required to engage landowners and the private sector. Hence devising and implementing landscape designs for more sustainable outcomes require clear communication of environmental, social, and economic opportunities and concerns.
Bio-oil derived via fast pyrolysis is being developed as a renewable fuel option for petroleum distillates. The compatibility of neat bio-oil with 18 plastic types was evaluated using neat diesel fuel as the baseline. The plastic materials included polyphenylene sulfide (PPS), polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polyoxymethylene (POM), POM copolymer, high density polyethylene (HDPE), polybutylene terephthalate (PBT), polypropylene (PP), polyethylene terephthalate glycol (PETG), polythiourea (PTU), four nylon grades, and four thermosetting resins. Specimens of each material were immersed in the test fuels for a period of 16 weeks to achieve full saturation. Except for PP and HDPE, the plastic materials underwent higher volume expansion in bio-oil than in the baseline diesel (which was negligible in most cases). This volume increase corresponds to the higher polarity of the bio-oil. PPS, PET, and PTFE were unaffected by bio-oil exposure, but modest swelling (between 2 and 5%) occurred for the two acetals (POM and POM copolymer), Nylon-12, PBT, PETG, and the four resin grades. More moderate swelling (8–15%) was noted for Nylon-6, Nylon-6/6, and Nylon-11, and excessive swell (>40%) occurred for PTU. The nonpolar nature of PP and HDPE matches that of diesel, leading to higher solubility (swell) in this fuel type. The relatively low volume expansion following exposure indicates that many of the existing infrastructure plastics (excluding PTU) should be suitable for use with bio-oil.
Energy market conditions have shifted dramatically since the USA renewable fuel standards (RFS1 in 2005; RFS2 in 2007) were enacted. The USA has transitioned from an increasing dependence on oil imports to abundant domestic oil production. In addition, increases in the use of ethanol, the main biofuel currently produced in the USA, is now limited by the blend wall constraint. Given this, the current study evaluates alternative biofuel deployment scenarios in the USA, accounting for changes in market conditions. The analysis is performed with a general equilibrium model that reflects the structure of the USA biofuel market as the transition to advanced biofuels begins. Results suggest that ethanol consumption would increase, albeit slowly, if current biofuel deployment rates of about 10% are maintained as persistently lower oil prices lead to a gradual increase in the consumption of liquid transportation fuels. Without the blend wall constraint, this study finds that the overall economic impact of a full implementation of the USA RFS2 policy is largely neutral before 2022. However, the economic impacts become slightly negative under the blend wall constraint since more expensive bio-hydrocarbons are needed to meet the RFS2 mandates. Results for a scenario with reduced advanced biofuel deployment based on current policy plans show near neutral economic impacts up to 2027. This scenario is also consistent with another scenario where the volume of bio-hydrocarbons deployed is reduced to adjust for its higher cost and energy content relative to deploying the mandated RFS2 advanced biofuel volumes as ethanol. The important role of technological change is demonstrated under pioneer and accelerated technology scenarios, with the latter leading to neutral or positive economic effects up to 2023 under most blend wall scenarios. All scenarios evaluated in this study are found to have positive long-term benefits for the USA economy.
This analysis estimates the cost of selected oil and biomass supply shocks for producers and consumers in the light-duty vehicle fuel market under various supply chain configurations using a mathematical programing model, BioTrans. The supply chain configurations differ by whether they include selected flexibility levers: multi-feedstock biorefineries; advanced biomass logistics; and the ability to adjust ethanol content of low-ethanol fuel blends, from E10 to E15 or E05. The simulated scenarios explore market responses to supply shocks including substitution between gasoline and ethanol, substitution between different sources of ethanol supply, biorefinery capacity additions or idling, and price adjustments. Welfare effects for the various market participants represented in BioTrans are summarized into a net shock cost measure. As oil accounts for a larger fraction of fuel by volume, its supply shocks are costlier than biomass supply shocks. Corn availability and the high cost of adding biorefinery capacity limit increases in ethanol use during gasoline price spikes. During shocks that imply sudden decreases in the price of gasoline, the renewable fuel standard (RFS) biofuel blending mandate limits the extent to which flexibility can be exercised to reduce ethanol use. The selected flexibility levers are most useful in response to cellulosic biomass supply shocks.
As a promising alternative energy source, biofuel imparts a remarkable role for the sustainability and security in energy sector. Strategies, including policy recommendations have been set to put forward the development and implementation of biofuel by different countries. Recent exploitation of Asian biofuels policy is one step towards destination. These types of activity behind the biofuels would be the catalyst for the productiveness of policy set by individual territory like Malaysia, Thailand, Vietnam, etc. This is the high time to standardize, policy recommendation and implementation of biofuels taking into consideration on the feedstock, geographical location, and availability. Pertinent comparison with well-established ASTM and European standards are highly recommended. Sector wise (viz. transportation, industrial) bio fuel policy is now crucial as well. Factors, which would be taking into account, prior to recommend a policy includes feed-stocks available, biofuel infrastructure of the country, compatibility with present automotive materials and performance and emission behaviour. This study sought to explore the investigation of several policies with regards to biofuel and advocates some key factors which could be helpful for diminution of biofuels inferiorities.
Exports of woody pellets from the southeastern United States (US) for European power plants have expanded since 2009, leading to concerns about major negative environmental effects. US exports of wood pellets have grown from essentially nothing in 2008 to 4.6 million metric tons in 2015, with 99% of US pellets being shipped to Europe. To examine effects of this recent expansion of the pellet industry on forest conditions, we use US Department of Agriculture Forest Service (USFS) Forest Inventory and Analysis (FIA) annual survey data for 2002–2014 to analyze changes in timberland trends since 2009 for two fuelsheds supplying pellets to the ports of Chesapeake, Virginia, and Savannah, Georgia. This analysis reveals that the Chesapeake fuelshed had significant increases in acreage of large trees and harvestable carbon after 2009. Furthermore, the timberland volume within plantations increased in the Chesapeake fuelshed after 2009. The Savannah fuelshed had significant increases in volume, areas with large trees, and all carbon pools after 2008. Increases in carbon in live trees for the Chesapeake fuelshed and all carbon pools for the Savannah fuelshed for the years before and after 2009 provide empirical support to prior estimates that production of wood-based pellets in the southeast US can enhance greenhouse gas sequestration. Both fuelsheds retained more naturally regenerating stands than plantations; however the number of standing dead trees increased within naturally regenerating stands and declined within plantations (but only significantly for the Savannah fuelshed). While the decrease in the number of standing dead trees per hectare for the Savannah fuelshed plantations after 2009 warrants investigation into its effects on biodiversity, others have recommended thinning and hardwood mid-story control within pine plantations to provide habitat for regionally declining bird species, which is consistent with use of biomass for energy and reducing the risk of fire. While all energy use affects the environment, these results show that benefits accrue when sustainable forest management provides wood pellets for energy that keep fossil fuel in the ground. By contrast urbanization is the greatest cause of forest loss in the SE US. It is essential to consistently monitor and assess forest conditions to assess changes, for exports of wood-based pellets for the southern US are expected to grow. Even though use of pellets for energy has more than doubled, the pellet industry constitutes < 1% of US forest products by weight. Therefore, any recent changes in SE US forest conditions are more likely related to the 2008 declines in the housing market. Continued analysis of annual FIA data using the methods outlined in this manuscript provides a scientifically valid approach for ongoing assessment.
The ongoing debate about costs and benefits of wood-pellet based bioenergy production in the southeastern United States (SE USA) requires an understanding of the science and context influencing market decisions associated with its sustainability. Production of pellets has garnered much attention as US exports have grown from negligible amounts in the early 2000s to 4.6 million metric tonnes in 2015. Currently, 98% of these pellet exports are shipped to Europe to displace coal in power plants. We ask, ‘How is the production of wood pellets in the SE USA affecting forest systems and the ecosystem services they provide?’ To address this question, we review current forest conditions and the status of the wood products industry, how pellet production affects ecosystem services and biodiversity, and what methods are in place to monitor changes and protect vulnerable systems. Scientific studies provide evidence that wood pellets in the SE USA are a fraction of total forestry operations and can be produced while maintaining or improving forest ecosystem services. Ecosystem services are protected by the requirement to utilize loggers trained to apply scientifically based best management practices in planning and implementing harvest for the export market. Bioenergy markets supplement incomes to private rural landholders and provide an incentive for forest management practices that simultaneously benefit water quality and wildlife and reduce risk of fire and insect outbreaks. Bioenergy also increases the value of forest land to landowners, thereby decreasing likelihood of conversion to nonforest uses. Monitoring and evaluation are essential to verify that regulations and good practices are achieving goals and to enable timely responses if problems arise. Conducting rigorous research to understand how conditions change in response to management choices requires baseline data, monitoring, and appropriate reference scenarios. Long-term monitoring data on forest conditions should be publicly accessible and utilized to inform adaptive management.
This report provides a status of the markets and technology development involved in growing a domestic bioenergy economy. It compiles and integrates information to provide a snapshot of the current state and historical trends influencing the development of bioenergy markets. This information is intended for policy-makers as well as technology developers and investors tracking bioenergy developments. It also highlights some of the key energy and regulatory drivers of bioenergy markets. This report is supported by the U.S. Department of Energy’s (DOE’s) Bioenergy Technologies Office (BETO), and, in accordance with its mission, pays special attention to the progress and development of advanced liquid transportation fuels from cellulosic and algal biomass.
The bioenergy economy engages multiple industrial sectors across the biomass-to-bioenergy supply chain—from agricultural- and forestry-based industries that produce biomass materials, to manufacturers and distributors of biomass-based fuels, products, and power, to the ultimate end-user markets. The breadth of this report focuses on activities that occur after the production of biomass.
After opening with a discussion of the overall size and composition of the bioenergy market, this report features two major areas: one detailing the two major bioenergy markets—biofuels and biopower—and another giving an overview of bioproducts that have the potential to enable bioenergy production.
The biofuels section is broken out by fuel type with sections on ethanol, biodiesel, and hydrocarbon fuels (gasoline, diesel, and jet fuel). Ethanol includes both conventional starch ethanol and cellulosic ethanol. This report covers the development of the conventional ethanol industry as a backdrop for emerging cellulosic ethanol production, and discusses challenges with absorbing new production into the market. Hydrocarbon fuels include the developing renewable hydrocarbon biofuels market. Finally, the report offers an overview of the renewable natural gas, biopower, and bioproducts markets.
In total, the information contained in this report is intended to communicate an understanding of portions of the U.S. bioenergy market.