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MIT researchers have developed a new application of carbon nanotubes that shows promise as an innovative approach to storing solar energy for use whenever it's needed. Storing the sun's heat in chemical form - rather than first converting it to electricity or storing the heat itself in a heavily insulated container - has significant advantages: in principle, the chemical material can be stored for long periods of time without losing any of its stored energy. The researchers created carbon nanotubes in combination with a compound called azobenzene. The resulting molecules, produced using nanoscale templates to shape and constrain their physical structure, and the concept that can be applied to many new materials. This material is vastly more efficient at storing energy in a given amount of space - about 10,000 times higher in volumetric energy density, making its energy density comparable to lithium-ion batteries, the researchers said. Ref.: Alexie M. Kolpak, Jeffrey C. Grossman, Azobenzene-Functionalized Carbon Nanotubes As High-Energy Density Solar Thermal Fuels, Nano Letters, 2011; 110705085331088 [DOI: 10.1021/nl201357n]

(PhysOrg.com) -- A Brigham Young University physics student and his professor had some fun with their new method of growing tiny machines from carbon molecules.

It's a sports car few people will be able to get their hands on. In production since last December, only 500 Lexus LFAs will be produced and they were already sold out in early June 2010 (see photo below). But it's not just its top speed of 325 kilometres per hour that's attracting buyers. The car is being used as a test bed for newly-designed parts made from carbon fibre and plastic. Compared to steel or aluminium, it makes the car stronger and lighter but producing these components is much more time-consuming: only one car is currently being assembled per day. One of the key technologies being used is a high-tech circular loom, guided by lasers, that can weave 3D objects (see video above). The machine's futuristic design attracted lots of media attention two years ago, but the video was pulled for fear it would expose company secrets. Now Lexus is revealing how the loom is being used to create complex 3D parts with varying thicknesses and curved shapes. For example, it can create roof rails by weaving fibres around a core, two layers at time, until twelve layers later a hollow roof rail is produced. The piece can then be moulded and injected with resin to create the finished part. The machine was also used to create the car's chassis and front pillars as well as the steering wheel.

The supply of secure, clean, sustainable energy is arguably the most important scientific and technical challenge facing humanity in the 21st century. Rising living standards of a growing world population will cause global energy consumption to double by mid-century and triple by the end of the century. Even in light of unprecedented conservation, the additional energy needed is simply not attainable from long discussed sources these include nuclear, biomass, wind, geothermal and hydroelectric. The global appetite for energy is simply too much. Petroleum-based fuel sources (i.e., coal, oil and gas) could be increased. However, deleterious consequences resulting from external drivers of economy, the environment, and global security dictate that this energy need be met by renewable and sustainable sources. The dramatic increase in global energy need is driven by 3 billion low-energy users in the non-legacy world and by 3 billion people yet to inhabit the planet over the next half century. The capture and storage of solar energy at the individual level personalized solar energy drives inextricably towards the heart of this energy challenge by addressing the triumvirate of secure, carbon neutral and plentiful energy. This talk will place the scale of the global energy issue in perspective and then discuss how personalized energy (especially for the non-legacy world) can provide a path to a solution to the global energy challenge. Daniel G. Nocera is the Henry Dreyfus Professor of Energy at the Massachusetts Institute of Technology, Director of the Solar Revolutions Project and Director of the Eni Solar Frontiers Center at MIT. His group pioneered studies of the basic mechanisms of energy conversion in biology and chemistry. He has recently accomplished a solar fuels process that captures many of the elements of photosynthesis outside of the leaf. This discovery sets the stage for a storage mechanism for the large scale, distributed, deployment of solar energy. He has b