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Hydropower is a valuable renewable energy source, but its effects on the downstream passage of many riverine fish species are not well understood. Turbines that are designed to function as safe downstream passage routes for fish are being developed with the goal of mitigating the effects of hydropower operations on the environment. In this paper, we present the results of a study conducted with the juvenile life stage of the Alewife Alosa pseudoharengus, a major migratory species on the Atlantic coast of North America. The test was conducted at a small hydropower plant located in Freedom, Maine, with a single Restoration Hydro Turbine (RHT) operating under 7.5 m of gross head. Groups of 140–170 fish were released into the intake of a 55‐cm‐diameter RHT and were recaptured with a specialized trap at the turbine discharge outlet. The combined immediate and 48‐h survival rates (±95% CI) for all treatments, corrected for control mortality, were 98.2 ± 2.0% and 100.0 ± 6.6%, respectively. The passage of Alewives through the runner region of the turbine was also captured with high‐speed video. The results of the study demonstrate that the RHT, which is designed for fish safety, is an effective way to pass juvenile alosines downstream at hydropower facilities. [ABSTRACT FROM AUTHOR]

Offshore wind energy is a growing industry in the United States, and renewable energy from offshore wind is estimated to double the country's total electricity generation. There is growing concern that land‐based wind development in North America is negatively impacting bat populations, primarily long‐distance migrating bats, but the impacts to bats from offshore wind energy are unknown. Bats are associated with the terrestrial environment, but have been observed over the ocean. In this review, we synthesize historic and contemporary accounts of bats observed and acoustically recorded in the North American marine environment to ascertain the spatial and temporal distribution of bats flying offshore. We incorporate studies of offshore bats in Europe and of bat behavior at land‐based wind energy studies to examine how offshore wind development could impact North American bat populations. We find that most offshore bat records are of long‐distance migrating bats and records occur during autumn migration, the period of highest fatality rates for long‐distance migrating bats at land‐based wind facilities in North America. We summarize evidence that bats may be attracted to offshore turbines, potentially increasing their exposure to risk of collision. However, higher wind speeds offshore can potentially reduce the amount of time that bats are exposed to risk. We identify knowledge gaps and hypothesize that a combination of operational minimization strategies may be the most effective approach for reducing impacts to bats and maximizing offshore energy production. [ABSTRACT FROM AUTHOR]

Cellulosic biofuel from forest thinning operations is a potential renewable energy source in regions with overstocked forests such as those in western United States. However, it is possible that biomass removal can deplete nutrients from soil, which can alter soil respiration (Rs) and exoenzyme properties, and potentially impact tree growth. This study evaluates the impact of biomass removal on Rs and exoenzyme properties and the capacity of soil amendments to counteract any potential effects. At two study locations, we created four post‐thinning biomass retention levels: full biomass removal (0×), full biomass retention (1×), double biomass retention (2×), and a no‐thin treatment. Four soil amendment treatments were applied to each biomass retention level: N fertilizer (F), biochar (B), fertilizer plus biochar (FB), and an untreated control (C). We evaluated treatment effects on Rs and activity of four exoenzymes to represent C‐cycling, N‐release, and P‐release processes. Biomass retention levels had no effect on Rs (p =.42) or exoenzyme activities (p >.29). Variation in exoenzyme activity was explained by location, season, soil organic matter, soil moisture content, and temperature. Variation in Rs was explained by the same variables, in addition to C‐cycling exoenzyme activity and soil pH. Soil amendments had no effect on exoenzyme activities (p >.49), and no main effect on Rs (p =.48), though amendments influenced Rs differently at each location (p =.02). Short‐term findings suggest small‐diameter biomass removal for cellulosic biofuel production will not impact Rs and exoenzyme properties, and paired with our tree growth study, provide evidence that biofuel systems are a feasible renewable energy source in the western North America. [ABSTRACT FROM AUTHOR]

A comprehensive examination is made of the characteristics and quality requirements of bio-oil from fast pyrolysis of biomass. An appreciation of the potential for bio-oil to meet a broad spectrum of applications in renewable energy has led to a significantly increased R&D activity that has focused on addressing liquid quality issues both for direct use for heat and power and indirect use for biofuels and green chemicals. This increased activity is evident in North America, Europe, and Asia with many new entrants as well as expansion of existing activities. The only disappointment is the more limited industrial development and also deployment of fast pyrolysis processes that are necessary to provide the basic bio-oil raw material. © 2012 American Institute of Chemical Engineers Environ Prog, 2012 [ABSTRACT FROM AUTHOR]

Current policy developments to reduce greenhouse gas (GHG) emissions are falling behind ecological change. The prevalent policy response to mitigate climate change is based on carbon trading mechanisms, which after the 2010 U.S. House of Representatives election and the Cancún climate negotiations, face an uncertain future. After losing its political majority in congress, the Obama Administration has also lost its ability to implement a national cap and trade system in the United States. The inability of climate negotiators to cement clear GHG reduction targets and a firm commitment for a second period for the Kyoto Protocol (KP) in Cancún means that the longevity and widespread applicability of existing carbon trading mechanisms will remain in doubt until the next United Nations Framework Convention on Climate Change (UNFCCC) negotiations in Durban, South Africa, at the end of 2011. These recent developments provide impetus to explore additional strategies to help achieve climate mitigation and the decarbonization of the energy systems of the Americas. Specifically, this article analyzes the feasibility of implementing new collaborative agreements such as the 'California-Chile Partnership for the 21st Century' to advance domestic implementation of renewable energy (RE) initiatives. This article also examines the potential role that new organizations such as the International Renewable Energy Agency (IRENA) can play in enhancing local capacity and policy development in Latin America. El desarrollo de políticas para reducir las emisiones de gases de efecto invernadero (GEI) se están rezagando frente a los cambios en materia ecológica. La principal respuesta al cambio climático está basada en los mercados de carbón que después de las elecciones de congreso y senado en Estados Unidos y de las negociaciones mundiales sobre el cambio climático en Cancún, representan una fórmula que enfrenta un futuro incierto. Después de perder su mayoría en el congreso, la administración del presidente Obama enfrenta también una reducción en sus posibilidades de implementar un sistema de límites y comercio de emisiones en Estados Unidos. Además, el hecho de que representantes gubernamentales no pudieran concretar en Cancún metas claras para reducir las emisiones de GEI o un acuerdo firme para un segundo periodo del Protocolo de Kioto, pondrá en duda hasta las negociaciones de finales de 2011, en Durban, Sudáfrica, la durabilidad y generalización de los mecanismos de comercio de emisiones que son parte del Protocolo de Kioto. Estos eventos recientes incitan a analizar estrategias adicionales que puedan ayudar a mitigar el cambio climático y a mejorar los sistemas energéticos de las Américas. Específicamente este artículo analiza la factibilidad de implementar nuevos acuerdos de colaboración similares al acuerdo 'Chile-California: Una asociación para el siglo XXI' con la meta de avanzar en la implementación de nuevas iniciativas para incrementar el uso de las energías renovables. Este artículo también explora los roles que organizaciones nuevas como la Agencia Mundial de Energías Renovables podrían ejercer para aumentar el conocimiento a nivel local y para ayudar en la gestión de políticas prácticas para el desarrollo de las energías renovables en América Latina. [ABSTRACT FROM AUTHOR]