Office of Energy Policy

Significance Conventional greenhouse gas mitigation policies ignore the role of global wetlands in emitting methane (CH 4 ) from feedbacks associated with changing climate. Here we investigate wetland feedbacks and whether, and to what degree, wetlands will exceed anthropogenic 21st century CH 4 emissions using an ensemble of climate projections and a biogeochemical methane model with dynamic wetland area and permafrost. Our results reveal an emerging contribution of global wetland CH 4 emissions due to processes mainly related to the sensitivity of methane emissions to temperature and changing global wetland area. We highlight that climate-change and wetland CH 4 feedbacks to radiative forcing are an important component of climate change and should be represented in policies aiming to mitigate global warming below 2°C.

Our paper explores potential future implications of climate change on building energy expenditures around the globe. Increasing expenditures result from increased electricity use for cooling, and are offset to varying degrees, depending on the region, by decreased energy consumption for heating. WE conducted an analysis using a model of the global buildings sector within the GCAM integrated assessment model. The integrated assessment framework is valuable because it represents socioeconomic and energy system changes that will be important for understanding building energy expenditures in the future. Results indicate that changes in net expenditures are not uniform across the globe. Net expenditures decrease in some regions, such as Canada and Russia, where heating demands currently dominate, and increase the most in areas with less demand for space heating and greater demand for space cooling. We explain these results in terms of the basic drivers that link building energy expenditures to regional climate.

Climate hazards and extreme weather affect all components of the electric grid system, from generation to end use. Increasing temperatures, decreasing water availability, more intense storm events, and sea level rise affect the ability of the electric grid to produce and transmit electricity from fossil, nuclear, and existing and emerging renewable energy sources. Most electricity infrastructure is built for past or current climate conditions. Due to long lifetimes, electricity systems are likely to be exposed more frequently to more extreme climate conditions than those for which they were designed, and may not operate as intended under changing climate conditions. Utilities, regulators, state energy offices, and other electricity system planners are beginning to conduct environmental risk assessments, develop climate resilience plans, and incorporate changing climate conditions into long-term planning processes. Here, we highlight the analytical resources available for sensitivity assessment of electrical grid components under extreme weather and climate, and identify gaps in the literature on quantitative methods available for assessment of component vulnerability.

Camelina (Camelina sativa) can be used to make biodiesel or biojet fuel. This study compares life-cycle energy, environmental impact and economic performance of making biodiesel versus biojet fuel from camelina oil. The data for camelina field production was obtained from a grower in western Washington, USA. Camelina seeds were crushed, and biodiesel and biojet fuel were produced at the University of Idaho's advanced biofuel research lab. Biodiesel was made via a transesterification reaction, and biojet was made using a technology called hydroprocessed renewable jet fuel. This research found that for a base-case scenario, where transportation and fuel additives were not needed, the ratio of energy in produced biofuel to its life-cycle energy was 3.6 for biodiesel and 1.8 for biojet fuel. Biodiesel reduced life-cycle GHG emissions by 69% compared to conventional diesel. In contrast, camelina biojet reduced GHG emissions by 56.6% compared to jet-A fuel. The cost of ingredients and utilities to make biodiesel was US 75¢/L compared to $2.19/L for biojet fuel taking no credit for byproducts. Considering the potential demand for biodiesel, the price of diesel, and price of jet fuel, it was concluded that biojet fuel is unlikely to compete economically with biodiesel in the foreseeable future.

Abstract This study contributes to the literature by using a spillover index method to examine the changing interrelations in volatility among corn and energy future prices. This methodology allows us to account for endogenously determined economic fundamentals and market speculation. After controlling for market trends and seasonality, we find relative large increases in volatility spillovers between corn, crude oil, and ethanol futures prices. Our results suggest that the cross-commodity spillovers provide useful incremental information in determining future price volatility; however, a commodity's own dynamics explain the largest portion of volatility spillovers.

This report describes a general approach for assessing climate change vulnerabilities of an electricity system and evaluating the costs and benefits of certain investments that would increase system resilience. It uses Tennessee Valley Authority (TVA) as a case study, concentrating on the Cumberland River basin area on the northern side of the TVA region. The study focuses in particular on evaluating risks associated with extreme heat wave and drought conditions that could be expected to affect the region by mid-century. Extreme climate event scenarios were developed using a combination of dynamically downscaled output from the Community Earth System Model and historical heat wave and drought conditions in 1993 and 2007, respectively.

Agribusiness, Resource/Energy Economics and Policy