1. Microbes could be engineered to store energy, according to a study published May 3 in the Journal of Biological Engineering. Energy storage works as an important complement to renewable sources such as wind and solar because their production varies according to the amount of wind or sunshine available. The microbes would store energy in the form of biofuels. If the theoretical process works, the microbes would borrow electrons from the electricity, use the energy to break apart carbon dioxide molecules from the air, and then take the carbon atoms to make biofuels.
  2. Another new technology might work for grid-level energy storage: potassium-oxygen batteries, invented in 2013. They're cheaper than today's widely used lithium-ion batteries and can store twice the energy. Researchers at The Ohio State University have just reported a breakthrough that greatly increases the number of times they can be recharged. "Now that we've shown that we can make a battery this cheap and this stable, then it makes it compete with other technologies for grid power backup," said Vishnu-Baba Sundaresan, professor of mechanical and aerospace engineering. He is co-author of a study about the research published on April 5 in Batteries & Supercaps.
  3. New fermentation techniques can cheaply and efficiently turn food waste into a biodegradable chemical that can be refined as a source of energy, say researchers at the University of Waterloo in Ontario, Canada. The process produces a carboxylate that can be refined into fuel. The carboxylate can also replace petroleum-based chemicals in such products as drugs and plastics. "People like me, environmental biotechnologists, look at food waste as a tremendous resource," said Hyung-Sool Lee, a civil and environmental engineering professor at Waterloo. He and his collaborators are publishing the latest in a series of papers about their work in Bioresource Technology.
  4. Here's a wild idea for getting the greenhouse gas methane out of the atmosphere: transform it into a different greenhouse gas. "If perfected, this technology could return the atmosphere to preindustrial concentrations of methane and other gases," said Rob Jackson, lead author of a study that discusses the idea, published May 20 in Nature Sustainability. Jackson is the Michelle and Kevin Douglas Provostial Professor in Earth System Science at Stanford University's School of Earth, Energy & Environmental Sciences. The study describes a process for converting methane into carbon dioxide, a much less potent contributor to global warming.