Teaching Wind Turbines Altruism to Rev-up Wind Farms

“Logic clearly dictates that the needs of the many outweigh the needs of the few.” So declares Spock, Star Trek’s Vulcan hero, as he sacrifices himself to save the Starship Enterprise and its crew in the 1982 film Star Trek: The Wrath of Khan. Today Stanford University researchers presented the clearest proof to date that self-sacrifice can also benefit wind farms. In their demonstration at an Alberta wind farm, one turbine sacrifices a fifth of its generating potential to enable better performance by neighboring turbines, boosting the group’s collective output.

And while Spock’s heroics necessitated a major plot twist to revive his character for the next Star Trek sequel, teaching turbines to behave altruistically requires just a small (but intelligent) tweak to their control systems. What they learn is how to share the wind. Continue reading “Teaching Wind Turbines Altruism to Rev-up Wind Farms”

The Hot Mess of Hawaii’s Renewable Power Push

My first contribution to award-winning Hakai Magazine, which covers coastal science, ecology and communities

Moloka‘i is a bastion of sanity and understatement at the center of the Hawaiian archipelago. Just 40 kilometers of open water away from O‘ahu, the island is a far cry from Honolulu’s hectic tiki bars and tourists, universities, cargo yards, and warships. On Moloka‘i, agriculture and subsistence hunting and fishing still sustain many of the 7,500 or so residents, and visitors are few. Those tourists who do make the hop over rank mailing a coconut home as their top experience.

On the surface, nothing about this bucolic place suggests it as the central hub around which a cleaner, high-tech electrical future might be built. Yet the island could serve as a model for Hawai‘i as the state navigates transitioning its entire power supply to renewable sources.

Honolulu-based Hawaiian Electric, the investor-owned utility that controls Moloka‘i’s grid, must meet a mandate from the state legislature to convert the five island grids it operates to 100 percent renewable energy by 2045. No utility on Earth knows for sure how to accomplish that yet. Pushing Moloka‘i there first and fast, Hawaiian Electric decided, would provide insight and inspiration.

Hawaiian Electric’s idea was to get Moloka’i off diesel generation by 2020. Alas, it is little closer to shutting down the diesels three years later. Can a small Hawaiian island and its utility get along well enough to teach the rest of the world how to get off fossil-fueled electricity?

Read the story or listen to the audio version at HakaiMagazine.com

Caffeine Cranks Up Solar Cells

Coffee is best served at 85°C — the same temperature used to accelerate endurance tests for electronics. Mere coincidence? Not if you’re a UCLA scientist developing solar cells using a promising new material. (Or a science journalist dishing up the latest dispatch from a world-leading electronic materials lab.) Taste for yourself at Spectrum

Spectrum: China’s Ambitious Plan to Build the World’s Biggest Supergrid

Wind rips across an isolated utility station in northwestern China’s desolate Gansu Corridor. More than 2,000 years ago, Silk Road traders from Central Asia and Europe crossed this arid, narrow plain, threading between forbidding mountains to the south and the Gobi Desert to the north, bearing precious cargo bound for Imperial Beijing. Today the corridor carries a distinctly modern commodity: gigawatts of electricity destined for the megacities of eastern China. One waypoint on that journey is this ultrahigh-voltage converter station outside the city of Jiuquan, in Gansu province.

Electricity from the region’s wind turbines, solar farms, and coal-fired power plants arrives at the station as alternating current. Two dozen 500-metric-ton transformers feed the AC into a cavernous hall, where AC-DC converter circuits hang from the 28-meter-high ceiling, emitting a penetrating, incessant buzz. Within each circuit, solid-state switches known as thyristors chew up the AC and spit it out as DC flowing at 800 kilovolts.

From here, the transmission line traverses three more provinces before terminating at a sister station in Hunan province, more than 2,300 kilometers away. There, the DC is converted back to AC, to be fed onto the regional power grid. The sheer scale of the new line and the advanced grid technology that’s been developed to support it dwarf anything going on in pretty much any other country. And yet, here in China, it’s just one of 22 such ultrahigh-voltage megaprojects that grid operators have built over the past decade.

The result is an emerging nationwide supergrid that will rectify the huge geographic mismatch between where China produces its cleanest power — in the north and west — and where power is consumed in the densely populated east. Moving energy via this supergrid will be crucial to maximizing China’s use of renewable energy and slashing reliance on coal.

Read on at IEEE Spectrum

Scientific American: Europe Stores Electricity in Gas Pipes

This month Denmark’s biggest energy firm, Ørsted, said wind farms it is proposing for the North Sea will convert some of their excess power into gas. Electricity flowing in from offshore will feed on-shore electrolysis plants that split water to produce clean-burning hydrogen, with oxygen as a by-product. That would supply a new set of customers who need energy, but not as electricity. And it would take some strain off of Europe’s power grid as it grapples with an ever-increasing share of hard-to-handle renewable power.

Turning clean electricity into energetic gases such as hydrogen or methane is an old idea that is making a comeback as renewable power generation surges. That is because gases can be stockpiled within the natural gas distribution system to cover times of weak winds and sunlight. They can also provide concentrated energy to replace fossil fuels for vehicles and industries. Although many U.S. energy experts argue that this “power-to-gas” vision may be prohibitively expensive, some of Europe’s biggest industrial firms are buying in to the idea.

European power equipment manufacturers, anticipating a wave of renewable hydrogen projects such as Ørsted’s, vowed in January that all of their gas-fired turbines will be certified by next year to run on up to 20 percent hydrogen, which burns faster than methane-rich natural gas. The natural gas distributors, meanwhile, have said they will use hydrogen to help them fully de-carbonize Europe’s gas supplies by 2050…

Read the rest at Scientific American

SPECTRUM: China Stumbles on Path to Solar Thermal Supremacy

In the final days of 2018 a 100-megawatt solar thermal generating station capable of running around-the-clock, 365-days-a-year connected to the Northwest China regional power grid. It was a race against time to commission the plant in temperatures as low as -20 celsius—and one that plant designer and builder Beijing Shouhang Resources Saving Co could not afford to lose.

“We must finish on time. Otherwise we may face a heavy financial problem,” says Chen Han, Shouhang’s director for international markets.

Shouhang was racing to beat the Chinese government’s December 31, 2018 deadline to secure a guaranteed price for the plant’s power. The deadline was part of an aggressive demonstration program launched in September 2016 to slash the cost of solar thermal power and catapult Chinese firms to the head of the global pack—much as China did with solar photovoltaics.

Alas, a little more than two years later, China has stumbled on the path to solar thermal supremacy. While Shouhang’s and two more of the program’s 20 approved projects met the deadline, four others were cancelled last year and the remaining 13 projects are in limbo. Continue reading “SPECTRUM: China Stumbles on Path to Solar Thermal Supremacy”

Making Power Grids 100 Percent Renewable

nsc_20180609-152x200Just a few  decades ago many experts fretted that variable power from wind turbines and solar panels would destabilize power grids. Today they’re debating the feasibility of 100 percent renewable power, which appears to be the most likely route to decarbonized energy systems by mid-century and thus our best shot at avoiding truly extreme climate change. Two of my recent feature articles explore what running grids on 100 percent renewable energy will take. My June cover story for NewScientist assesses the big picture, identifying the changes required in consumer behavior and power supplies and the technologies available to deliver them. My feature for Scientific American, meanwhile, takes a deeper dive into power grids, and how weather smarts must be built in to make the most of weather-driven “fuel” such as winds and sunlight. Both articles are behind paywalls online. One more reason to consider subscribing to two of the world’s top science magazines!