Rectifying antennas – "rectennas" – are used as parasitic power capture devices that absorb radio frequency (RF) energy
and convert it into usable electrical power. Constructing such devices to absorb and rectify at optical wavelengths has proved impractical in the past, but the advent of carbon nanotubes and advances in microscopic manufacturing technology have allowed engineers at the
Georgia Institute of Technology to create rectennas that capture
and convert light to direct electrical current. The researchers believe that their
creation may eventually help double the efficiency of solar energy harvesting.
Thanks to an increase in solar panels and wind turbines, as well as a particularly sunny and windy quarter, renewable energy has supplied a record 25% of the UK’s energy mix in Q2 2015, leapfrogging coal for the first time to come into second place behind gas fired electricity. It’s nearly a 10% increase on the same period last year.
Biofuels can be made from various source materials such as waste from the winemaking industry and woody biomass. Reseachers are also looking for new methods to improve its environmental credentials as there is still controversy as to how green biofuels really are. Now, a team at the Catalysis Institute at Cardiff University is hoping to make biofuel production more efficient and sustainable by recycling the leftovers from the process.
Sunlight can be used to generate electricity either through a
photovoltaic effect, or by harnessing the heat produced by the light.
There are already hybrid systems that combine both, but scientists at
Korea's Yonsei University have now developed a type of hybrid setup that
they claim works better.
For decades we've been promised that hydrogen fuel cells will revolutionize our lives, but it always seems to be around the next corner. But that hasn't stopped one UK company from pursuing a near future in which iPhones and other devices are completely disconnected from the electrical grid and instead use embedded fuel cells to power themselves for a full week between recharges.
It may not be the first airport to fit solar panels to its terminals, but India's Cochin International Airport is set to become the first in the world powered entirely by solar. Situated in Kochi, the airport handled 6.8 million passengers in the 2014-15 financial year and forecasts a 300,000-tonne (330,700-ton) reduction in carbon emissions over the next 25 years as a result of the switch to solar.
The scientists that revealed the "world's first solar battery" last year are now, following some modifications, reporting its first significant performance milestone. The device essentially fits a battery and solar cell into the one package, and has now been tested against traditional lithium-iodine batteries, over which the researchers are claiming energy savings of 20 percent.
Wind turbines might be common sight all around the world, but situating them in open fields or on breezy ridges isn't always a practical option. Ideas like placing turbines under bridges have been proposed, but is that a viable alternative? According to new research out of Europe, the answer is yes.
It's now fairly common to hear about batteries being used to store power
generated by solar cells. A group of Indian scientists, however, have
eliminated the middleman. They've created a battery that incorporates a
titanium nitride-based photoanode in place of a conventional anode,
allowing the battery to charge itself using solar or artificial light.
Researchers have discovered an unlikely source of renewable energy, the naturally-occurring cycle that is water evaporation. Scientists at New York's Columbia University replicated this process in the laboratory and harnessed its energy to power tiny machines, one of which was a moving, miniature car. The team says the technology could potentially to be scaled up to one day draw power from huge resting bodies of water such as bays and reservoirs.