Volts:

A company called Direct Connect is currently in the development and permitting phase of a privately financed, $2.5 billion project called the SOO Green HVDC Link, a proposed 349-mile, 2.1-gigawatt (!), 525-kilovolt transmission line to run underground along existing railroad from Mason City, Iowa, to the Chicago, Illinois, area. It aims to go into operation in 2024.

Going underground will allow the line to minimize environmental and visual impact. It will be much more resilient than an overhead line against weather, temperature shifts, sabotage, or squirrels

Two side-by-side cables will run through tubes of Cross-Linked Polyethylene (XLPE) and will be self-contained, lightweight, and easy to handle. They won’t get hot, interfere with signaling equipment (unlike AC lines), or affect rail operations. There are fiber-optic sensors along the lines to monitor sound and heat for any problems. 

(Nemo Link, the world’s first 400 kilovolt line using XLPE, runs undersea between the UK and Belgium; it began operation in January 2019.)

Running alongside the railroad means SOO Green will have no need to claim land via eminent domain. Almost all of that railroad is owned by Canadian Pacific (one of seven large “class one” railroads in the US), so there are a tractable number of parties to deal with. 

A deal like this offers railroads a new passive revenue stream; royalty fees well exceed what they get from similarly buried fiber-optic lines, of which there are more than 100,000 miles along US railroads. And it’s also a chance for railroads to be part of a positive sustainability story. 

The project is privately funded, so there will be no need for any complicated cost-allocation formulas. The financiers (including Siemens, which very rarely puts direct capital in transmission projects) will make their money back from those who use the line — the suppliers that put power on it, the shippers that sell power across it, and the buyers that consume the power — through competitive bidding for capacity. SOO Green is holding an open solicitation right now to allocate its 2,100 megawatts among them.

Read the rest of this entry »

Science Alert:

The stretch of Arctic ice between Greenland and the Canadian Arctic Archipelago is known as ‘the Last Ice Area’, thought by scientists to have the best chance of surviving the climate crisis – but new research suggests it could be more vulnerable to disappearing than previously thought.

It’s the oldest and the thickest stretch of ice in the Arctic region, and up to this point it’s managed to survive even the warmest summers on record. There are even hopes that it will eventually act as the foundation of a spreading Arctic ice region, if we can get the planet to begin cooling down again.

Maybe not, according to a new analysis of satellite data looking specifically at ice arches along Nares Strait, which is 40 kilometres (25 miles) wide and 600 kilometres (373 miles) long.

Ice arches aren’t traditional arches at all, they’re key patches of ice that form seasonally and prevent other pieces of ice from entering a body of water. The Nares Strait and its arches could play a crucial role in whether or not the Last Ice Area survives through the peak of global warming.

“The ice arches that usually develop at the northern and southern ends of Nares Strait play an important role in modulating the export of Arctic Ocean multi-year sea ice,” write the researchers in their published paper.

“We show that the duration of arch formation has decreased over the past 20 years, while the ice area and volume fluxes along Nares Strait have both increased.”

Simply put, the Nares Strait ice arches that effectively hold the Last Ice Area in place are becoming less stable. The risk is that this old ice will not just melt in place, but also break up and drift southwards into warmer regions, speeding up the melting process.

The ice arches look like bridges on their sides, blocking the movement of ice from north to south. The problem is that the arches are breaking up earlier in the year than they have previously, allowing more ice to flow through the Nares Strait.

Every year, according to observations, the ice arches are breaking up a week earlier than before. The ice blockage is becoming thinner and less of a barrier, and that is leading to changes further north – it’s estimated that ice movement in the Last Ice Area is increasing twice as fast as it is in the rest of the Arctic.

Read the rest of this entry »