Tag: UHV

China’s Grid Architect Proposes a “Made in China” Upgrade to North America’s Power System

Transmission lines in the United States and Canada require approval from every state and province traversed, and that political fragmentation hinders deployment of long power links of the type connecting vast swaths of territory in regions such as China, India, and Brazil. As a result, few studies detail how technologies that efficiently move power over thousands of kilometers, such as ultrahigh-voltage direct current (UHV DC) systems, might perform in North America. Earlier this week, the Beijing-based Global Energy Interconnection Development and Cooperation Organization (GEIDCO) stepped in to fill that gap, outlining an ambitious upgrade for North America’s grids.

GEIDCO’s plan promises to greatly shrink North America’s carbon footprint, but its boldest prescriptions represent technical and economic optimizations that run counter to political interests and recent trends. “Thinking out of the box is how you solve complicated, difficult problems,” said former Southern California Edison CEO Ted Craver in response to the plan. But GEIDCO’s approach, he said, raises concerns about energy sovereignty that could prove difficult to settle. As Craver put it: “There’s theory and then there’s practice.”

The proposed North American transmission scheme was unveiled on Tuesday at an international transmission forum in Vancouver, Canada, by Liu Zhenya, the former State Grid Corp. of China chairman who launched GEIDCO in 2016. While at State Grid, Liu championed the development of the world’s first 800- and 1,100-kilovolt UHV DC lines and the first 1,000-kV, UHV AC transmission. State Grid has deployed them to create a brawny hybrid AC-DC electricity system that taps far-flung energy resources to power China’s densely-populated and industrialized seaboard.

Through GEIDCO, Liu is proselytizing for UHV deployment worldwide. At the Vancouver meeting, Liu warned of “unimaginable damage to mankind” if greenhouse gas emissions continued at their current pace. He argued that beefy grids moving power across and between continents are a prerequisite for accessing and sharing the world’s best wind, solar, and hydropower resources, and thus dialing-down fossil fuel consumption. Continue reading “China’s Grid Architect Proposes a “Made in China” Upgrade to North America’s Power System”

by pfairley

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

by pfairley