The relationships between energy use in food systems, food system productivity, and energy resource constraints are complex. Moreover, ongoing changes in food production and consumption norms concurrent with urbanization, globalization, and demographic changes underscore the importance of energy use in food systems as a food security concern. Here, we review the current state of knowledge with respect to the energy intensity of agriculture and food systems. We highlight key drivers and trends in food system energy use along with opportunities for and constraints on improved efficiencies. In particular, we point toward a current dearth of research with respect to the energy performance of food systems in developing countries and provide a cautionary note vis-à-vis increasing food system energy dependencies in the light of energy price volatility and concerns as to long-term fossil energy availabilities.

Concrete infrastructure represents an enormous investment of materials, energy, and capital, and results in significant environmental burdens and social costs. There is an ongoing effort to identify material alternatives to conventional concrete. Life cycle assessment (LCA) is an important tool to evaluate the environmental performance of alternative infrastructure materials and systems. Here, we present a comparative LCA of two bridge deck systems over a 60 year service life: one using conventional steel expansion joints and the other based on a link slab design using a concrete alternative, engineered cementitious composites (ECC). The ECC link slab design is expected to extend the bridge deck service life and reduce maintenance activities. A life cycle model was developed that accounts for materials production and distribution, construction and maintenance processes, construction-related traffic congestion, and end-of-life management. Results indicate that the ECC bridge deck system has significant adv...

Lithium is a critical energy material in part due to an array of emerging technologies from electric vehicles to renewable energy systems that rely on large‐format lithium ion batteries. Recent growth in demand for lithium is primarily from increased use in batteries, which comprised 46% of total lithium by end use in 2017. These technologies are often deployed to improve environmental sustainability, yet the environmental effects and sustainability of the resources they rely on are often not well understood, especially as demand increases over time. This is the first in a two part article series that together quantify the lithium resource use and its environmental effects over time by coupling a resource production model and life cycle assessment model. In this first part, a novel resource production model is developed to create scenarios of future lithium demand and production characteristics (e.g., timing, location, and ore type). These scenarios are then used to create a life cycle assessment in part two that captures temporal and spatial changes in production systems over time. Results of the resource production model show global lithium resources range from 293 to 527 million metric tons (Mt) of lithium carbonate equivalent (LCE). Global production will likely increase from 237,000 metric tons LCE in 2018 to 4.4–7.5 Mt LCE/year by 2100. Even with rapidly increasing demand, production from high‐grade brines may satisfy most lithium demand through 2035. Though resources can meet demand through 2100, development of lower grade and unfavorable deposits is likely required after 2050.