Navigant Research Blog

National High-Voltage Transmission Interconnect Project Continues to Face Support and Financing Hurdles

— August 7, 2015

The proposed Tres Amigas interconnection has been viewed as a critical development for establishing solid superconducting high-voltage direct current (HVDC) linkages between the three primary transmission networks in the United States. These networks include the Western Electric Coordinating Council (WECC), ERCOT, and the Eastern systems.  The project is thought to be critical to maintaining reliability and connecting the tremendous wind and solar renewable energy resources in the upper Midwest and the Southwest, with the urban population centers in the Central Midwest and the East.  The project has been in planning and early development stages since 2008, and it has struggled to get approximately $1.6 billion in funding for a highly technical project that involves large scale high-voltage alternating current transmission lines (HVAC) to HVDC lines necessary for synchronization of the three systems. It also incorporates re-conversion to HVAC at the interconnect points with the other networks.

In late July, the Federal Energy Regulatory Commission (FERC) announced that it had approved a request from the Southwest Power Pool (SPP) to void an interconnection agreement between Tres Amigas and Southwestern Public Service (SPS), primarily based on Tres Amigas missing multiple payments and a number of performance milestones. While the missed payments are a small portion of the total $1.6 billion dollar project, partnerships with adjacent transmission operators are critical to the completion of the project.

In previous Navigant Research blogs, I have discussed the development of a north-south transmission highway between the northern Midwest wind farms, the utility scale solar in the Southwest, and the population centers in Nebraska, Kansas, and Texas. Interestingly, the SPP transmission plans I saw show that this conceptual idea is beginning to come to fruition as new 345 kV transmissions systems are being built and older systems are upgraded.  Many of these projects have been completed by the transmission owner/entities in the region to address congestion issues in corridors like the Omaha/Kansas City to the Texas Panhandle route.

Anticipating Coal Plant Retirements

However, coal plant retirements across the lower Midwest, East Coast, and southeastern United States will have a serious impact on electric reliability across those regions, according to the North American Electric Reliability Corporation (NERC). Forward-thinking electric transmission companies are anticipating this and are now building new West-to-East transmission to deliver wind power from the High Plains to population centers in the Midwest and Southeast that will be hit hard by the retirements.  The Tres Amigas interconnection may be a critical part of the puzzle that is the modernization of the national versus regional transmission grids.  While Navigant Research expects that it will ultimately be funded by numerous transmission utilities, the full funding for the multi-billion dollar project has yet to fall into place.

You can read more about the Tres Amigas project and HVDC transmission systems in my syndicated reports, including High-Voltage Transmission Systems  and High-Voltage Direct Current Transmission Systems.


Massive Hydro, HVDC Project Brings Latest Submarine Cable Technologies to Eastern Canada

— June 17, 2015

During the past 2 months, I’ve written a number of blogs that illustrate the truly epic nature of high-voltage direct current (HVDC) submarine electric transmission projects in Europe and North America. What has become apparent is that these projects almost always have significant underground and overhead components that are part of the larger HVDC market.

Nalcor Energy’s Lower Churchill Project has a fascinating twist, as it includes the construction of two new hydroelectric generation stations near Muskrat Falls in Labrador, Canada. This large-scale HVDC electric transmission interconnection project will ultimately be more than 1,100 km long, linking Muskrat Falls near Happy Valley-Goose Bay, Labrador, to Soldiers Pond, Newfoundland, and transmitting hydropower between the two points.

Nalcor Energy awarded Alstom a 350 kV HVDC turnkey contract to design, supply, and install a point-to-point HVDC solution for the Labrador-Island Transmission Link, including multiple high-voltage alternating current (HVAC) to HVDC converter stations at Muskrat Falls, and in Soldiers Pond in Newfoundland. Alstom is also building two cable compounds on both shores of the Strait of Belle Isle to connect submarine cables crossing the strait to the onshore overhead transmission lines. Nalcor Energy indicates that this project will establish itself as a valuable power-producing asset for decades. It is also expected to generate significant employment and economic benefits, including billions of dollars in income for Newfoundland and Labrador businesses, according to the company.

On the Rocks

The project was initiated in Forteau and Shoal Cove in 2013. Given the rocky terrain, significant horizontal drilling was necessary, with drill rigs and other equipment operating on both sides of the strait to create boreholes for the submarine cables. Drilling activities were completed in August 2014.  The following figure illustrates the scope of the project that includes multiple deep-channel HVDC submarine cable installations.  It shows the configuration of the submarine cable system across the channel between Labrador and Newfoundland.  Interestingly, the cable had to be submerged using a drilled conduit to ensure that the span was deep enough to avoid major icebergs, shipping anchors, and other hazards.  Subsequently, the cable was buried under a 12-meter wide by 1.5-meter high rock berm.

Drilling Activities

Jim Diagram

(Source: Nalcore Energy)

In 2016, a cable installation vessel will begin installing the three transmission cables on the sea floor. Rock berms will then be placed over each cable by a rock-laying vessel to protect the cables from marine vessel traffic and fishing activity. Transmission compounds and connectors will also be constructed in Forteau and Shoal Cove.  You can learn more about this project in Navigant Research’s forthcoming Submarine Electric Transmission report.


Regional Tensions Surround Baltic Sea Submarine Electric Transmission Project

— June 12, 2015

Transmission system operators in Sweden and Lithuania, Svenska Kraftnät and LITGRID turtas AB, are installing a 280-mile submarine electric transmission cable system between the two countries, with short, underground high-voltage direct current (HVDC) cables running to converter stations onshore in each country. The 700 MW ±300 kV HVDC transmission system and converter stations will link the electricity networks in the Baltic and Nordic regions.  The interconnections in both countries will use voltage source converter technologies and will be located in Nybro, Sweden and in Klaipeda, Lithuania. Both transmission system operators are confident that the installation will go live near the end of 2015. The link between Lithuania and Sweden can be seen in the figure below.

Submarine Electric Transmission Cable System: Sweden to Lithuania

SET blog

(Source: European Network of Transmission System Operators for Electricity)

The NordBalt submarine cable project is being installed by ABB, and it represents the world’s longest HVDC light submarine and underground cable.  The completed project is expected to strengthen the security of the power supply in the Baltic countries and in southern Sweden, integrating an emerging joint 330 kV Baltic electricity market with the 400 kV Nordic and European markets.  At the same time, additional capacity will facilitate power exchange, enhance grid reliability, and improve the security of electricity supply at in each country.  The system has features such as active alternating current (AC) voltage support, providing greater network stability and black-start capability, which enables faster grid restoration after a blackout.  The project is expected to fully integrate with the future Pan-European grid using HVDC technologies, with a $650 million budget over the course of the project. 

This epic project, given its regional configuration, gives a fascinating glimpse into the political tension in the region.  An undersea power cable aimed at reducing the Baltic states’ energy dependence on Russia has emerged as the latest point of friction in a region increasingly enveloped in a Cold War atmosphere. Sweden and Lithuania, which are at either end of the proposed submarine electric transmission system, have complained that Russian warships have repeatedly interrupted the installation.  The latest such incident, the third in 2 months, occurred last week when the Russian Navy ordered a vessel involved in the cable-laying work to leave the area, according to Sweden and Lithuania. Although the vessel was in Lithuania’s exclusive economic zone, it was sent away for as long as 10 hours.

The Lithuanian Foreign Ministry has expressed an emphatic protest to the Russian ambassador and may consider legal action against Russia were a similar incident to happen again. Sweden stands beside  Lithuania, taking the matter very seriously.  Interestingly, but not surprising, Russia’s Foreign Ministry referred questions to the Defense Ministry, which declined to comment. Russian state media have said the presence of construction vessels disturbed a Russian military exercise.  Tensions around this epic submarine electric transmission project and military operations in the region appear to be at an all-time high.


Submarine Cable Project to Link Canada, New York

— May 26, 2015

The Champlain Hudson Power Express Project is an epic example of the creative solutions that major transmission utilities and third parties are undertaking to interconnect adjacent markets across borders. This hybrid 337-mile project will carry more than 1,000 MW of renewable power from Canada to the New York metropolitan areas. The project includes sections of high-voltage direct current (HVDC) submarine power cables running through Lake Champlain, the Hudson, East, and Harlem Rivers, with other sections using HVDC underground with the existing Delaware & Hudson Railroad and CSX Transportation railroad right of ways.

The $2.2 billion dollar project is expected to be completed and commissioned in 2017, linking the Montreal area to the New York City neighborhood of Astoria, Queens.  The transmission link between Canada and New York is being developed by Transmission Developers Inc. (TDI), a Blackstone Group, L.P, and is designed to transport electricity from hydropower and wind resources in eastern Canada and feed it directly into the New York City electricity market. The Quebec section of the line and high-voltage alternating current (HVAC) to HVDC converter station is being built and will be operated by TransÉnergie, the transmission division of Hydro-Québec, one of the largest Canadian utilities.

The following graphic shows the scope of the project, starting out at the Hertel converter station in Quebec, where HVAC is converted to HVDC.  The HVDC line runs under Lake Champlain for over 100 miles and then through railroad right of ways for 126 miles.  It then runs under the Hudson River to New York City over about 100 miles, with a few underground transitions in New York City.

Champlain Hudson Power Express

Champlain Hudson Power Express

(Source: Transmission Developers, Inc.)

It’s clear that these HVDC submarine and underground systems are complex solutions that have less environmental impact than overhead transmission lines with associated right of way and eminent domain issues.

The majority of HVDC submarine electric transmission projects are being planned and completed in the European market, where tremendous off-shore wind resources in the Nordic countries, Germany, and the United Kingdom are coming online. It’s great to see that creative projects such as the Champlain Hudson Power Express transmission system are also happening in North America. Over the next 5 to 10 years, this type of interconnection/intertie between independent system operator/regional transmission organization (ISO/RTO) regions and countries will be critical to delivering adequate and increasingly renewable power resources. For more information, look for my upcoming report (expected to publish in 2Q 2015) on submarine electric transmission, which will include regional and global forecasts for capacity and revenue through 2024.



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