Concrete surrounds us in our cities and stretches across the land in a vast network of highways. It’s so ubiquitous that most of us take it for granted, but many aren’t aware that concrete’s key ingredient, ordinary portland cement, is a major producer of greenhouse gases. (more…)
Berkeley Lab Researchers Report First Fully Integrated Artificial Photosynthesis Nanosystem
In the wake of the sobering news that atmospheric carbon dioxide is now at its highest level in at least three million years, an important advance in the race to develop carbon-neutral renewable energy sources has been achieved. Scientists with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) have reported the first fully integrated nanosystem for artificial photosynthesis. While “artificial leaf” is the popular term for such a system, the key to this success was an “artificial forest.”
“Similar to the chloroplasts in green plants that carry out photosynthesis, our artificial photosynthetic system is composed of two semiconductor light absorbers, an interfacial layer for charge transport, and spatially separated co-catalysts,” says Peidong Yang, a chemist with Berkeley Lab’s Materials Sciences Division, who led this research. “To facilitate solar water- splitting in our system, we synthesized tree-like nanowire heterostructures, consisting of silicon trunks and titanium oxide branches. Visually, arrays of these nanostructures very much resemble an artificial forest.” (more…)
Collaboration at JBEI Identifies the First Enzyme Linked to Galactan Synthesis
Galactan is a polymer of galactose, a six-carbon sugar that can be readily fermented by yeast into ethanol and is a target of interest for researchers in advanced biofuels produced from cellulosic biomass. Now an international collaboration led by scientists at the U.S. Department of Energy (DOE)’s Joint BioEnergy Institute (JBEI) has identified the first enzyme capable of substantially boosting the amount of galactan in plant cell walls.
Unlike ethanol, advanced biofuels synthesized from the sugars in plant cells walls could replace gasoline, diesel and jet fuels on a gallon-for-gallon basis and be dropped into today’s engines and infrastructures with no modifications required. Also, adanced biofuels have the potential to be carbon-neutral, meaning they could be burned without adding excess carbon to the atmosphere. Among the key challenges to making advanced biofuels cost competitive is finding ways to maximize the amount of plant cell wall sugars that can be fermented into fuels. (more…)
Blake Simmons (left) and Harvey Blanch of the Joint BioEnergy Institute led the development of a technoeconomic model for optimizing biorefinery operations. Image cedit: Roy Kaltschmidt, Berkeley Lab Public Affairs
Researchers at the U.S. Department of Energy’s Joint BioEnergy Institute (JBEI) have created a technoeconomic model that should help accelerate the development of a next generation of clean, green biofuels that can compete with gasoline in economics and well as performance. This on-line, wiki-based model enables researchers to pursue the most promising strategies for cost-efficient biorefinery operations by simulating such critical factors as production costs and energy balances under different processing scenarios.
“The high production cost of biofuels has been the main factor limiting their widespread adoption,” says JBEI’s Daniel Klein-Marcuschamer. “We felt that a model of the biorefinery operation that was open, transparent about the assumptions it uses, and updatable by the community of users could aid in guiding research in the direction where it is most likely to reduce the production cost of biofuels.” (more…)
