Turning water into watts

Physics World  March 3, 2020 Most approaches to harvesting mechanical energy from ocean waves rely on finding a way to move a conducting wire through a magnetic field to generate electricity. Researchers at Georgia Institute of Technology designed triboelectric nanogenerators (TENGs) in small plastic spheres, about the size of oranges, that float in water. As the waves jostle the sphere, material inside bumps against the outer shell, generating charges. Th charges then flow through an attached wire. In lab tests each sphere could generate about 10 mW of power enough for powering small devices such as sensors on buoys used […]

Russian scientists found an effective way to obtain fuel for hydrogen engines

EurekAlert  February 20, 2020 Catalysts used for releasing hydrogen from an H2O molecule are made from platinum, or molybdenum which are expensive hence the output energy is expensive too. Researchers in Russia used thin films of molybdenum sulfide deposited on the surface of glassy carbon instead. In this case, the material consumption will be minimal, and the surface area of the catalyst will be the same as if it was completely made from molybdenum sulfide. They measured electrochemical characteristics which indicated that the differences in the achievable hydrogen evolution reactions performances of the films could be caused by their unique […]

New droplet-based electricity generator: A drop of water generates 140V power, lighting up 100 LED bulbs

Science Daily  February 5, 2020 An international team of researchers (USA – University of Nebraska, Hong Kong, China) found that the continuous droplets impinging on Polytetrafluoroethylene (PTFE) provides a new route for the accumulation and storage of high-density surface charges. The device consists of an aluminium electrode, and an indium tin oxide (ITO) electrode with a film of PTFE deposited on it. The PTFE/ITO electrode is responsible for the charge generation, storage, and induction. When a falling water droplet hits and spreads on the PTFE/ITO surface, it naturally “bridges” the aluminium electrode and the PTFE/ITO electrode, translating the original system […]

Something from nothing: Using waste heat to power electronics

EurekAlert  February 12, 2020 A thermocell can convert environmental thermal energy to electric energy via thermal charging effect. However, the output voltage is low and depends on temperature. Researchers in Japan developed a thermocell containing a material that exhibited a temperature-induced phase transition of its crystal structure. Just above room temperature, the atoms in this solid material rearranged to form a different crystal structure. This phase transition resulted in an increase in output voltage from zero to around 120 mV, representing a considerable performance improvement over that of existing thermocells. They were able to finely tune the phase transition temperature […]

China’s Next Five-Year Energy Plan Will Shape the Global Energy Future

Next Big Future  January 23, 2020 The 14th Five-Year Plan will cover 2021-25. The full plan will be released around March 2021, but partial drafts and releases will be published in 2020. China is projected to reduce the proportion of coal in its energy mix to below 58% by 2020. There are proposals to set a target of coal usage at 55% of China’s energy mix by 2030 for the 14th five-year plan covering 2021-2025. Greenhouse gas emissions to peak around 2025-2030. In March the China Electricity Council suggested that coal-power capacity should grow to 1,300 GW by 2030. Hydropower […]

High-performance anode for all-solid-state Li batteries is made of Si nanoparticles

EurekAlert  December 23, 2019 In conventional liquid electrolytes, the use of polymeric binders is necessary to hold the active material particles in the electrode together and maintain their adhesion to the surface of metal current collectors. The repeated huge volume change of Si causes the particle isolation and thus leads to losing the active material, which results in a continuous capacity loss. Researchers in Japan have shown that in solid electrolytes, an Si anode composed only of commercial Si nanoparticles prepared by spray deposition exhibits excellent electrode performance, which has previously been observed only for film electrodes prepared by evaporation […]

Scientists harvest energy from light using bio-inspired artificial cells

Nanowerk  December 12, 2019 Researchers at the Argonne National Laboratory created cell-like hollow capsule structures through the spontaneous self-assembly of hybrid gold-silver nanorods held together by weak interactions. By wrapping these capsules’ walls with a light-sensitive membrane protein called bacteriorhodopsin, the researchers were able to unidirectionally channel protons from the interior of the artificial cells to the external environment. The key to the research came from coupling the group of artificial cells that were generating protons to a second, distinct group of artificial cells. These cells contain molecular motor machinery that uses the proton gradient to generate ATP which is […]

Using mountains for long-term energy storage

Science Daily  November 11, 2019 To close the gap between existing short- and long-term storage technologies an international team of researchers (Austria, Denmark, Italy) proposes Mountain Gravity Energy Storage (MGES) and hydropower which moves sand or gravel from a lower storage site to an upper elevation. The higher the height difference the greater the amount of stored energy as this technology is constrained to the topography of the location. MGES cost varies from 50 to 100 $/MWh of stored energy and 1–2 M$/MW of installed capacity. It could be a feasible option for micro-grids, for example, small islands and isolated areas, […]

System provides cooling with no electricity

MIT News  October 30, 2019 An international team of researchers (USA – MIT, Chile) has developed polyethylene aerogel (PEA)—a solar-reflecting (92.2% solar weighted reflectance at 6 mm thick), infrared-transparent (79.9% transmittance between 8 and 13 μm at 6 mm thick), and low-thermal-conductivity (kPEA = 28 mW/mK) material that can be integrated with existing emitters to address these challenges. Using an experimental setup that includes the custom-fabricated PEA, they demonstrated a daytime ambient temperature cooling power of 96 W/m2 and passive cooling up to 13°C below ambient temperature around solar noon. This work could greatly improve the performance of existing passive […]

Nano bulb lights novel path

Eurekalert  September 19, 2019 Researchers at Rice University made an incandescent light source by breaking down a one-element system into two or more subunits. They put sub-elements together in such a fashion that they interact with each other. The idea is to rely upon collective behavior, not just a single element. Breaking the filament into many pieces provides more degrees of freedom to design the functionality. The resonator’s output can be controlled by damping the lossy resonator or by controlling the level of coupling through a third element between the resonators. The ability to tune the oscillator phase provides new […]