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The advent of cheap, renewable hydrogen is nigh

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Hydrogen gas has been the pipe dream fuel of clean-energy advocates for decades. Splitting electrons from H2 molecules creates electricity and a waste product: pure H2O. It has the added benefit of being storable (albeit at high pressures or low temperatures), and it can refuel a car or a generator in minutes, as opposed to batteries, which can take hours to recharge.

Unfortunately, most of the hydrogen that is mass-produced today is made by synthesizing it from natural gas (more specifically, methane, or CH4). But it's also possible to make hydrogen using electricity and water, using an electrolyzer. If that electricity is renewable electricity, hydrogen can be nearly carbon neutral in its lifecycle.

The problem is that the electrolyzers that can make hydrogen from renewable energy have historically been prohibitively expensive. But that's changing, according to a new paper in Nature Energy.

Researchers from universities in Germany and at Stanford University created a financial model for a wind farm connected to a hydrogen electrolyzer. They modeled electricity and hydrogen prices as if this theoretical system were based in Germany and then in Texas. The researchers concluded that "renewable hydrogen is projected to become cost competitive with large-scale fossil hydrogen supply within the next decade."

The model

Using research from "journal articles, industry data, publicly available reports, and interviews with industry sources," the researchers built a theoretical model to determine whether wind energy paired with an electrolyzer could be profitable. The system was normalized to a one-kilowatt system (a common technique for this kind of economic modeling) and assumed to be paired with a polymer electrolyte membrane (PEM) electrolyzer, "which can be ramped up rapidly and attain a near-constant efficiency once a small threshold utilization has been reached," the paper noted.

In the model, an investor could either sell all the electricity back to the grid, or, when electricity prices were low, it could use that energy to run the PEM electrolyzer and sell the resulting hydrogen at market prices. The price of electricity was based on historical prices observed in Germany and Texas every hour for a year.

The researchers determined that to build a system with both wind and a hydrogen electrolyzer, the break-even price for hydrogen needs to be €3.23 per kilogram in Germany and US$3.53 per kilogram in Texas. Currently, those prices are about right for small- and medium-scale hydrogen production, but not for large-scale fossil-fuel-synthesized hydrogen, which retails in the range of €1.5 to 2.5 per kilogram ($1.70 to 2.82 per kilogram).

That explains why we don't see more renewable hydrogen systems in the wild today. Currently, big hydrogen systems like Germany's hydrogen train run on Hsynthesized from fossil fuels. Early hydrogen project developers are working to explore renewable systems in the US, but few concrete plans have been made.

System costs projected to decline

But the researchers figured that they could look at trends in wind and renewable hydrogen systems and make an estimate as to when those systems would start popping up. Using historical prices from between 2003 and 2016, they found that the prices of renewable hydrogen systems fell by approximately 4.77 percent. That's because as the cost of wind turbines and electrolyzers fell annually, the capacity factor of wind turbines also increased annually (so a single turbine produces more electricity).

That suggests that "in about a decade, renewable hydrogen will also become competitive with the lower prices paid for large-scale industrial hydrogen."

Of course, large-scale industrial hydrogen will have to compete with cheap, non-renewable energy like fossil fuels at that point. As mentioned above, storing hydrogen can be a challenge, so building appropriate refueling stations is not a trivial task. Hydrogen fuel cell vehicles are also not as common as electric vehicles at the moment, though both industries are nascent enough that hydrogen could catch up if it found a niche in transportation (in long-haul trucking, for instance). But bringing the cost of renewable hydrogen on the same level as methane-synthesized hydrogen is a step in the right direction, and it might encourage more investment in fuel cell vehicles and generators.

Getting to parity faster

To speed up the development of renewable hydrogen facilities, the paper suggests that minor incentives from governments could help. In Germany, renewable power enjoys what's called a "feed-in tariff" that acts as a sort of price premium for clean energy. To bolster the development of renewable hydrogen, the country could waive "the requirement that renewable energy be fed into the grid to be eligible for the price premium." That is, renewable hydrogen could benefit from a mandated price premium over fossil fuel-synthesized hydrogen.

In the US, the researchers recommend an Investment Tax Credit for electrolyzers, just like other renewable energy sources (from solar to biomass to geothermal to batteries) receive. In the US, "for every rebate increment of 10 percent, the break-even prices for renewable hydrogen are shown to accelerate the competitiveness with large-scale fossil hydrogen supply by about 1.5 years," the paper estimates.

Solar has benefitted from years of a 30-percent Investment Tax Credit. If renewable hydrogen systems were to receive the same, we might see competitive renewable hydrogen four and a half years sooner.

Nature Energy, 2019, DOI: https://doi.org/10.1038/s41560-019-0326-1 (About DOIs)

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superiphi
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Idle, Bradford, United Kingdom
719 days ago
hi superiphi, thanks for your post. it's help for me.
acdha
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Searching for the ships Cortés burned before destroying the Aztecs

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Underwater archaeologists are searching the waters off Playa Villa Rica, about 75 kilometers (46.6 miles) north of Veracruz on Mexico’s Gulf coast, for what’s left of conquistador Hernán Cortés’ long-abandoned fleet.

Scouring the seafloor

In 1519, at the very last moment, the Spanish governor of Cuba revoked the charter of an expedition to Mexico after a fierce argument with its leader. But the defiant Cortés set sail with 11 ships and 300 men anyway, and by July, he had worked his way along the Yucatan coast to Veracruz. There, eager to march inland to the Aztec capital of Tenochtitlan, Cortés destroyed 10 of his 11 ships, cutting off his men’s only hope of retreat and leaving them with no option but to head inland.

The expedition ultimately destroyed the Aztec Empire and began the long and often brutal process of colonizing Mexico. Almost no one gave the ships a second thought.

Five hundred years later, underwater archaeologist Roberto E. Junco Sánchez, of Mexico’s National Institute of Archaeology and History (INAH), is giving them that second thought. With a team of colleagues, he’s crisscrossing the waters off Villa Rica with magnetometers and side-scan sonar, looking for Cortés’ abandoned ships. The team is scanning the sea floor for traces of metal that may be the remains of 500-year-old ships’ fittings.

But it turns out a lot of metal is buried beneath the sand off Villa Rica. So far, the team’s survey has turned up between five and six dozen magnetometer targets, any of which could be either Cortés’ ships, a pile of modern junk, or something else entirely.

“Once we have the mag hits, we investigate them using a portable handheld magnetometer, then excavate and look for traces of old metal,” Junco told Ars Technica. If the divers find a shipwreck, they’ll radiocarbon-date samples of the wood to see if it lines up with the dates of Cortés’ expedition. And if there’s enough of the hull left, its design and construction may also yield clues to its origin.

Sixteenth-century high tech

There’s probably not much left of Cortés’ ships after all these centuries on the bottom; tropical waters make short work of wood, canvas, and rope unless they’re well buried. Usually, what's left is the lower section of the hull, protected by seafloor sediment and sometimes the ship’s own ballast stones. Sanchez estimates that about two meters of sediment now cover the wrecks. “It will be interesting to see the state of preservation,” he told Ars.

The state of the wrecked ships may clear up a minor historical debate about how, exactly, Cortés destroyed his fleet. The earliest reports claimed he simply ran them aground, but later historians eventually embraced a more dramatic version of events that featured the conquistador burning his entire fleet.

If found, the scuttled ships could tell archaeologists something about a little-known period of shipbuilding: the cutting-edge 16th-century engineering that paved the way for European colonization, for better or worse. “There are very few early ships located and few 16th-century wrecks known and studied,” Junco told Ars Technica. “These very early ships are the kind of technology that mapped America and the Pacific Islands; they were good vessels to discover and start the process of discovery and colonization.”

The search continues

And Cortés’ ships may not be alone down there.

“There is also the possibility that we might have the fleet of Pánfilo de Narváez, who also, we think, scuttled his ships in the area,” Junco told Ars Technica. Narváez raced to Mexico in 1519 with orders from the Cuban governor to stop Cortés and his mutinous expedition. Despite arriving with a larger force, he failed and lost an eye in the process.

Divers have checked roughly a third of the targets so far, and they’ve found no sign of a shipwreck. But Junco says he’s optimistic. The survey area is relatively small, and they’re looking for the remains of 10 ships clustered together, so it’s less of a needle-in-a-haystack proposition than shipwreck surveys sometimes are. And in 500 years, the INAH team is only the second one to give it a serious try.

“There was an important researcher in the 19th century, Francisco del Paso y Troncoso, who in 1891 put hard-helmet divers in this area to look for the ships,” Junco told Ars Technica. Today’s searchers have the benefit of magnetometers, side-scan sonar, and significantly more advanced dive gear. “Our next move is to keep the mag survey and verify the rest of the anomalies we have,” said Sanchez.

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superiphi
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Green New Deal

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Why Sustainable Agriculture Should Support a Green New Deal.

I don't know whether these ideas about agriculture are valid, biologically and economically. I don't know enough about that field to try to judge, and I don't know of anyone I can regard as an authority on the matter.

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superiphi
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The Ascension in Anglo-Saxon England

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Many fine examples of medieval art remain hidden within the pages of manuscripts. These illuminated books reflect the huge variety of artistic expression present in England and France during the early Middle Ages, as discussed in more detail on our new Medieval England and France, 700-1200 website. Biblical events provided...
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Sutton Hoo and Anglo-Saxon East Anglia

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The British Library’s landmark exhibition, Anglo-Saxon Kingdoms: Art, Word, War, is open until 19 February 2019. Alongside some of the most significant manuscripts from our own collections, and important loans from other institutions, are a number of outstanding archaeological finds. Among them are artefacts from Sutton Hoo. The Sutton Hoo...
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The Sacred Pig

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Greek terracotta pig votive circa 5th century BCE

Pigs in their various forms, from wild boar to domesticated swine, are extremely ambivalent figures in myth, sacred in some contexts, demonic in others, or (in the paradoxical manner so common to magical tales) both revered and shunned at the same time. The pig as a sacred animal seems to belong to the early goddess religions, about which our knowledge is far from complete -- but carvings and other artifacts found all across what is now western Europe indicate that the pig was an aspect of the Great Goddess, associated with fertility, the moon, and the season cycles of life and death.

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As Alison Hawthorne Deming explains in her excellent book Zoologies:

"The process of pig domestication began in the Tigris Basin thirteen thousand years ago; in Cyprus and China, eleven thousand years ago. Sculptures of pigs have been unearthed in Greece, Russian, Yugoslavia, and Macedonia. Marija Gimbutas, in her keystone work The Godddess and Gods of Old Europe, writes that 'the fast-growing body of the pig will have been compared to corn growing and ripening, so that its soft fats apparently came to symbolize the earth itself, causing the pig to become a sacred animal probably no later than 6000 BC.'  The goddess of vegetation sometimes wears a pig mask. Sometimes the pig figurine, fleshy and round, is scored with traces of grain pressed into the clay or is graced with earrings. The prehistoric goddess of vegetation dates back to Neolithic times and is predicessor to Demeter, the Greek goddess of fertility and harvest, whose temple at Eleusis was built in the second century BCE.

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"The Eleusinian Mysteries," Deming continues, "became the principal religious ritual of ancient Greece, begun circa 1600 BCE. Originally a secret cult devoted to Demeter, the rites honored the annual cycle of death and rebirth of grain in the fields. The resurrection of seeds buried in the ground inspired the faith that similar resurrection might A figure of Demeter with a pig, circa 400 BCE, found near Athensawait the human body laid to rest in the earth. The religious rituals of the Eleusinian Mysteries lasted two thousand years, became the official state religion, and spread to Rome. They laid the groundwork for Christianity's belief in resurrection and were ultimately overthrown by the Roman emperor in the fourth century CE.

"The canonical source of Demeter's story, the 'Homeric Hymn to Demeter,' dates from about a thousand years into the practice of these rituals. It is called Homeric because it employs the same meter as The Iliad and The Odyssey -- dactylic hexameter, the rhythm of 'Picture yourself in a boat on the river / With tangerine trees and marmalade skies.'

"The foundation of the Mysteries is Demeter's power over the fertility of the land. When her daughter Persephone is stolen by Hades to be his lover in the underworld, the mother's grief is so acute that she refuses to let the fields produce grain. People are in danger of starving, but Demeter resists, saying there will be no crops until she sees her daughter return. When Persephone does come back, after many trials among mortals and much dealing making among the gods, Demeter's sudden transformation of bare ground into a 'vast sheet of ruddy grain' marks the miracle of fruition returning after a fallow time and sparks the fertility cult of the mysteries. This metamorphosis occurs in mythic time, so it is safe to say that it continues in the present moment for the mind embracing its truth.

Marble piglet votive

"Suckling pigs played a key role in the festival of Thesmophoria, a three-day rite that took place in October, the time for autumn sowing of barley and winter wheat. As I write this, the word sow catches my eye, as both noun for the female pig and verb for planting seeds. The Oxford English Dictionary tells me that the two words come from different Old English roots, but nonetheless history delivers the homograph to modernity still carrying freight from the ancients. Pig = grain. And the corollary, embedded in prehistoric art: pig = Earth = survival."

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In stories from later periods of classical myth, the pig appears in a number of hero tales: not as a sacred animal now but as a monster to be slain. Thesues, for example, kills the Crommyonian Sow who is ravaging the countryside near Crommyon. This was no ordinary pig, but the daughter of Echidna (a snake-woman) and Typhone (the monstrous son of Gaia), named after the woman who raised her. The Crommoyonian Sow was, in turn, the mother of the Calydonian Boar sent by Artemis to punish the region of Calydon, where the king had neglected the rites of the gods. The creature is killed in the famous Hunt of the Calydonian Boar by the king's son Meleager, aided (for complicated reasons) by the goddess Atlanta.

The Calydonian Hunt shown on a Roman frieze at the Amsmolean Museum in Oxford

Pigs appear all throughout The Odyssey, though largely in the background of the story: Odysseus is the king of Ithaca, an island reknown for its farmland and herds of fat swine. He is the son of Laërtes, an Argonaut who participated in the Hunt of the Calydonian Boar. During his long journey home from the Trojan War, Odysseus encounters Circe the sorceress, who turns his men into swine (and other animals)...and then falls in love with Odysseus and releases the crew from enchantment. When our hero reaches Ithaca at last, he hides himself in his swineherd's house while taking measure of all that's gone on in his absence, and it's there, among dogs and pigs, that he is reunited with his son Telemachus. He finally makes his way to his own house, disguised, where his elderly nurse recognizes him: while washing his feet, she spies an old scar he received from a boar hunt many years before.

Aneas, another hero of the Trojan War, is also associated with pigs. In Book VIII of Virgil's Aeneid, the river god Tiberinus appears to Aeneas in a dream to tell him his son is destined to found the great city of Alba. He will know place when he sees this omen: a spotless white sow with thirty white piglets. This comes to pass and the city, which will be Rome, is duly founded.

Circe by Alan Lee

Aneas and his son with the White Sow of Alba

The poor pig does not fare well in the myths the Middle and Near East, including those of the Abrahamic religions, where the animal is viewed as an unclean and defiled creature in Jewish, Muslim, and Christian stories alike. It is tempting to attribute the pig’s fall from grace to its association with women's mysteries -- but while this may have played a role, there are also practical reasons why the animal was shunned. As Mark Essig writes in his fascinating book Lesser Beasts:

Greek terracotta askos in the form of a boar, circa 4th c. BCE"By the start of the Iron Age, about 1200 bc, elites in the Near East had begun to see pigs as polluting, a view that arose in part from the habits of urban pigs. Though cities had grown large, sanitation systems had not kept pace. Residents threw garbage into the streets or piled it in heaps outside their doors....Dogs and pigs had first domesticated themselves by scavenging human waste, but now that role made them pariahs. Filthy animals offended the gods and therefore were excluded from holy places. The people of the Near East practiced many different religions, but all agreed that the key sacrificial animals were sheep, goats, and cattle and that pigs were unclean. In Mesopotamia and Egypt, pigs never appear in religious art. The Harris Papyrus, which describes religious offerings made by King Ramses III, includes a detailed list of every desirable item to be found in Egypt and the lands it had conquered, including plants, fruits, spices, minerals, and meat. Pork does not appear on the list. 'The pig is not fit for a temple,' a Babylonian text reads, because it is 'an offense to all the gods.' A Hittite text declares, 'Neither pig nor dog is ever to cross the threshold' of a temple. If anyone served the gods from a dish contaminated by pigs or dogs, 'to that one will the gods give excrement and urine to eat and drink.' "

(You can read an engrossing except from Lessig's book here.)

From the tomb of Ramses II

The pig fared better among the Norse and the Celts, for whom -- as with the Demeter cults -- it was valued not only as a source of food but also as a divine animal, associated with the cycle of birth and death, the moon, the underworld, and intuitive wisdom.

In Norse myth, both Freyr (god of virility and prosperity) and his sister Freyja (goddess of love, sex, and fertility) held the wild boar under special protection, and are sometimes depicted together in a chariot drawn by a heavenly boar with golden bristles. In Hyndluljóð, an Old Norse poem that forms part of the Poetic Eddas, Freyja has a companion boar named Hildisvíni, whose name means "Battle Swine."

Bronze boar statue from the Celtic sanctuary at Neuvy-en-Sullias (1st c. BCE)

In Celtic Ireland, not only were wild boars and sows held in high esteem, but so were domestic pigs; and the swineherds who tended them were credited with magical powers. Their herds of swine would have been semi-wild, foraging for food in the forests of kings; the herders were thus semi-wild themselves and imbued with the woodland's magic. The Táin Bó Cúailnge and other ancient texts tell stories of swineherds who battle each other in contests of magic, or who utter prophesies at key moments in the lives of heroes and kings.

From the Mabinogion illustrated by Alan Lee

In Welsh legend, the enchantress Ceridwen (possessor of the Cauldron of Inspiration which turns Gwion Bach into Taliesin) is referred to as The White Sow; and in some Welsh folklore traditions she had the power to assume that shape. The following passage from The Mabinogion describes the introduction of pigs to that land:

"Lord," said Gwydion [to Math son of Mathonwy],I have heard tell there have come to the South such creatures as never came to this Island." "What is there name?" said he. "Hobeu, lord." "What kind of animals are those?" "Small animals, their flesh better than the flesh of oxen. But they are small and they change names: moch are they called nowadays." "To whom do they belong?" "To Pryderi son of Pwyll, to whom they were sent from Annwn [the Underworld], by Arawn king of Annwn."

Whereupon Gwydion concocts a plan to steal these animals for his own land, setting off all manner of troubles....

Warwick Goble

In fairy tales, lowly pig keepers usually turn out to be princes or princesses in disguise. Likewise, the "Pig-Sty Prince" of Arthurian lore, a child found abandoned among the swine, turns out to be cousin to Arthur himself and grows up to win the hand of a princess.

Harry G. Theatre

Today, science has confirmed that pigs are highly social and intelligent animals....which only makes their abuse by the modern system of factory farming all the more horrific. Perhaps if we recognized them (and all creatures) as sacred beings this could finally change.

The pig photographs in this post are from my friend Elizabeth-Jane Baldry (pictured below), a harpist, composer, and filmmaker here in Chagford who kept pigs for a time to forage in her beautiful woodland, Pigwiggen Wood. The sow is Blossom, and the piglets are ones she gave birth to back in 2010. They have since been re-homed...but not eaten, I assure you!

Ej & friend

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The art above (top to bottom): a Greek terracotta pig votive, circa 5th c. BCE; a figure of Demeter with pig found near Athens, circa 5th c. BCE; a marble pig votive; The Calydonian Hunt shown on a Roman frieze at the Amsmolean Museum, Oxford; Circe and her pigs in The Wanderings of Odysseus, illustrated by Alan Lee; a marble relief showing Aneas and his son with the White Sow of Alba; a Greek terracotta boar askos, circa 4th c. BCE; imagery from the Egyptian tomb of Ramses II depicting how Horus would judge souls in the afterlife, reincarnating the bad ones as pigs; a bronze boar statue from the Celtic sanctuary at Neuvy-en-Sullias, circa 1st c. BCE; "Gwydion steals the pigs of Pryderi" from The Mabinogion, illustrated by Alan Lee; The Pig Keeper by Warwick Goble (1862-1943); and The Pig-Style Prince by Harry G. Theaker (published in 1925).

The quotations above come from Zoologies: On Animals and the Human Spirit by Alison Hawthorne Deming (Milkweed Editions, 2014), and Lesser Beasts: A Snout-to-Tail History of the Humble Pig by Mark Essig (Basic Books, 2015). The poem in the picture captions, "Circe's Power" by Louise Gluck, is from The New Yorker (April 10, 1995), with thanks to Christine Norstrand for introducing me to it. The passage from The Mabinogion comes from the Gwyn Jones & Thomas Jones translation (Dragon's Dream edition, 1982). All rights to the quoted text is reserved by the authors.

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Michdevilish
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superiphi
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