Updated: Jan 20, 2021
As research continues into alternative energy sources for the 21st century and beyond, sceptics and enthusiasts alike are marshalling evidence in support of their own vision for a sustainable future. We are still in the foothills of that research and it will take time before we can establish conclusive data on current research projects, the use of new technologies and their own environmental impact on the planet.
The following articles provide an illustration of the dilemma at the heart of the green agenda. The first, comprising two articles from The Economist, discusses the way that current environmental and covid constraints could act as a spur to greater innovation and a new sustainable period of economic growth. The second is a research-based article on the specifics of hydrogen-powered flight and its wider use in daily lives more generally.
"Aviation is under pressure to curb carbon-dioxide emissions by burning less kerosene. And talk of building hydrogen-manufacturing-and-delivery infrastructure for other purposes, such as heating and ground transport, is getting serious, meaning that hydrogen might become available as a commodity, rather than having to be made specially. The balance of advantage may thus be shifting. So a few brave souls are looking once again at the idea of hydrogen-powered flight."
This particular debate would appear to hinge around the use of electric batteries or hydrogen-powered fuel cells. "Proponents of fuel cells say... that these are better than batteries for powering flight because the cells plus their associated fuel store many times more energy per kilogram than batteries can manage. “Batteries really give you the acceleration. But they won’t give you the range,” says Robert Steinberger-Wilckens, a chemical engineer at the University of Birmingham, in Britain. Battery technology is improving, but big breakthroughs will be needed before longer journeys with passengers and freight on board become possible."
And, critically, the article also recognises the trade-off between innovation and its environmental impact:
"Redesigning a turbine engine to run on the stuff (hydrogen) will be a multi-billion-dollar endeavour. Hydrogen burns faster than kerosene, and also burns hotter. That means materials exposed to its combustion experience greater stresses. It also risks increasing the pollution generated in the form of oxides of nitrogen, which would partially negate the environmental benefits of burning hydrogen. And it would be useful as well to arrange matters so that some of the energy used to compress or liquefy the hydrogen for storage could be recovered and put to work."
The full article and enclosed link to the original can be read here:
As an addendum and counter-argument to the broadly optimistic and supportive analysis of renewable research above, we enclose the following article from the Daily Telegraph Saturday Supplement dated 16.01.21
In particular, the author (Harry de Quetteville) cites the environmental hazards of 'rare earth extractions,' the process by which elements are mined for the production of parts of wind-powered technology:
"Most offshore turbine magnets weigh about 650kg for every MW (megawatt) of power they generate. And for most, about a third of the magnet is composed of materials with exotic names like neodymium and dysprosium, from a group of metals known as rare earths.
And while rare earths are not rare, they can be very, very dirty. Yet they are very special too. ‘They have such amazing properties,’ says Guillaume Pitron, a French journalist and documentary-maker who reports on the global commodities trade, and has now written a book, The Rare Metals War. ‘Magnetic, catalytic, optical. You cannot do the green energy revolution without them.’
The article continues: "As these rare elements are distributed in tiny quantities, vast piles of ore need to be dug up, processed and refined to produce minuscule amounts. For a single kilo of gallium – used in energy-efficient light bulbs – 50 tonnes of rock needs to be excavated, according to Pitron.
Here is the article in full with a link to the original at the bottom: