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Power-hungry, fossil-fuel dependent Japan has successfully tested a system that could provide a constant, steady form of renewable energy, regardless of the wind or the sun.

For more than a decade, Japanese heavy machinery maker IHI Corp. has been developing a subsea turbine that harnesses the energy in deep ocean currents and converts it into a steady and reliable source of electricity. The giant machine resembles an airplane, with two counter-rotating turbine fans in place of jets, and a central ‘fuselage’ housing a buoyancy adjustment system. Called Kairyu, the 330-ton prototype is designed to be anchored to the sea floor at a depth of 30–50 meters (100−160 feet).


Tested in one of the world’s strongest ocean currents, a prototype generator could herald the start of a new stream of renewable energy.

Chemical reactions that are driven by light offer a powerful tool for chemists who are designing new ways to manufacture pharmaceuticals and other useful compounds. Harnessing this light energy requires photoredox catalysts, which can absorb light and transfer the energy to a chemical reaction.

MIT chemists have now designed a new type of photoredox that could make it easier to incorporate light-driven reactions into . Unlike most existing photoredox catalysts, the new class of materials is insoluble, so it can be used over and over again. Such catalysts could be used to coat tubing and perform chemical transformations on reactants as they flow through the tube.

“Being able to recycle the catalyst is one of the biggest challenges to overcome in terms of being able to use photoredox catalysis in manufacturing. We hope that by being able to do flow chemistry with an immobilized catalyst, we can provide a new way to do photoredox catalysis on larger scales,” says Richard Liu, an MIT postdoc and the joint lead author of the new study.

Ford Motor Company recently filed a patent for a combustion engine that will run on hydrogen, Motor1 reports. The patent isn’t like your normal hydrogen-powered vehicle which uses a propulsion system that converts energy stored as hydrogen to electricity via a fuel cell. The patent Ford filed is for a turbocharged combustion engine that runs on hydrogen.

Muscle Cars and Truck, which initially discovered and reported on the patent, noted that on paper, Ford’s engine should be capable of operating across a wide range of air/fuel lambda, which is the Greek letter used to represent a fuel’s stoichiometric value as 1.00, with values depending on torque demands. MCT also noted that internal exhaust gas recirculation and valve timing will be used to control combustion.

MCT quickly touched upon the importance of the stoichiometric value of a fuel, which is the ratio by which all of the fuel is mixed with all of the oxygen to produce a competitive burn. Notably, Ford’s new method of turbocharged hydrogen will explore lambda values in excess of 2.00. This means that the new engine would be able to operate in an extremely lean state and use more than double the amount of air required for the stoichiometric combustion of hydrogen. You can read more about this here.

Green Gravity, a startup proposing to use old mine shafts for gravitational energy storage, has secured AUD 1.4 million ($990,000) in its first formal capital raise.


From pv magazine Australia

Green Gravity is turning to the former cornerstone of Australia’s wealth, coal mining, to remove the final hurdle for a fully renewable electricity system. It is proposing to lift and release ultra-heavy weights in legacy mine shafts, in a reimagining of how the universal force of attraction, gravity, can be used to store renewable energy.

While the hyped Swiss startup Energy Vault recently hit rocky waters, Green Gravity CEO Mark Swinnerton is adamant that his company has distinct merits, many of which stem from the fact that its concept is rooted in redeploying abandoned but very abundant infrastructure. In recent weeks, Green Gravity secured AUD 1.4 million in its first formal fundraising round with a range of private investors, “with plenty of surplus interest,” Swinnerton told pv magazine Australia.“We are working toward a larger raise in a few months time when we firm up the capital cost for the demonstration plant.”

Circa 1978


Summary. The energetics of the gravitationally powered dynamo have been studied with the aid of a compressible-earth model which allows for the growth of the solid inner core. The basic premise of this study is that as the Earth gradually cooled over geological time the solid inner core continually accreted dense material which crystallized from an outer core composed of a molten binary alloy. This process requires a continual rearrangement of matter which generates the fluid motions needed to sustain the dynamo. These motions maintain the outer core in a well-mixed state, in apparent contradiction to Higgins & Kennedy’s hypothesis that the outer core is stably stratified. The vigour of these motions is dependent primarily upon the composition of the solid inner core, but is surprisingly independent of the density of the light constituent in the core. If the solid core is composed entirely of heavy metal, then as much as 3.7 × 1012 W may be transferred from the core to the mantle as a result of cooling and gravitational settling. This is roughly equal to estimates of the amount of heat conducted down the adiabat in the core, but it is argued that there is no direct relation between the amount of heat conducted down the adiabat and the amount transferred to the mantle if the convection is driven non-thermally. The gravitational energy released per unit mass of the solid inner core is remarkably constant and may be as much as 2 × 106J/kg, roughly five times the value of the latent heat of iron. These values are reduced if the solid inner core contains some light constituents. It was found that the efficiency of the gravitationally powered dynamo may exceed 50 per cent, a much higher figure than is possible for either the thermally or precessionally driven dynamo. Also, the amount of gravitational energy available to drive the dynamo in the future is many times that expended so far. The size of the magnetic field sustained by gravitational settling was related to the density jump at the inner—outer core boundary and the field strength was estimated to lie between 390 and 685 G, strongly suggesting that the dynamo is of the nearly-axisymmetric type developed by Braginsky.