Navigant Research Blog

Google Expands Data Center Fleet at Retiring TVA Coal-Fired Generation Site

— July 7, 2015

In late June, Google announced plans to site its 14th massive data center at the Widows Creek Tennessee Valley Authority (TVA)  coal-fired generation site in Alabama.  The $600 million facility will also re-purpose the 60-year-old coal-fired site, which will soon be retired, leveraging existing electric transmission and distribution infrastructure. This infrastructure might have otherwise become another stranded utility asset, ultimately abandoned.  While the data center is planned to be powered by 100 percent renewable energy, access to existing electric transmission infrastructure provides access to renewable power not generated at the data center site, as well as additional backup capabilities sometimes necessary to operate 24/7.

The size of and the electrical power requirements for Google data centers are huge. Google has a history of building creative large-scale data centers, which are some of the largest electric power consumers on the transmission grid.  The company’s data center designs are typically state of the art, utilizing the latest cooling technologies to keep aisle after aisle of servers running at optimal temperatures on a 24/7 basis.  Google’s designs are also known for their creative use of renewable energy where possible.

TVA’s Widows Creek Facility


(Source: Tennessee Valley Authority)

Model  Behavior

Gary Demasi, Google’s director of data center energy and location strategy, reported that, “The idea of re-purposing a former coal generating site and powering our new facility with renewable energy — especially reliable, affordable energy that we can count on 24/7 with the existing infrastructure in place — was attractive.”

Patrick Gammons, Google’s senior manager for data center energy and location strategy added, “Thanks to an arrangement with Tennessee Valley Authority, our electric utility, we’ll be able to scout new renewable energy projects and work with TVA to bring the power onto their electrical grid. Ultimately, this contributes to our goal of being powered by 100% renewable energy.”

With the seemingly insatiable need for power, infrastructure, and real estate that large data centers have, this 100% renewable data center plan provides a model for other utilities nationwide to use when determining how to redevelop coal plant sites. With the Energy Information Administration’s (EIA’s) recent announcement that the coal plant retirement timetable is accelerating, in part due to the U.S. Environmental Protection Agency’s Clean Power Plan mandate, Google’s clean energy leadership is certainly an inspiration.


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, Svenska Kraftnät, and in Lithuania, 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 two 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.


California Drought Implications for Electric T&D Becoming Clearer

— June 2, 2015

The implications of climate change and the 4-year California drought are just beginning to become clear. The snowpack in the Sierras, where reservoirs and dams ultimately feed the canal system that delivers water to the Bay Area, the Central Valley, and Southern California, is at an all-time low. While strict water rationing is mandatory for some residential and commercial consumers in many parts of the state, there are other forces at play. Some are laudable, and some are not.

On one hand, many city and municipal water districts are offering new rebate programs and incentives to remove lawns that require watering and replace them with xeriscape landscapes that require little if any water. On the other hand, the agricultural economy in California’s Central Valley needs water for almonds, pistachios, and a host of other products, and the large farms are reportedly pumping down the aquifers to support their business.

Thinking Long Term

Prolonged drought could also have major effects on the electric transmission and distribution (T&D) system, as well as on the water delivery system across California.

  • The major water agencies, including the Association of California Water Agencies (ACWA) managing the canal system between Northern and Southern California, have for many years been not only a major end-use consumer, but also a demand response resource for the California Independent System Operator (CAISO).  If the volume of water moving south through the Central Valley and over the mountains into the Los Angeles basin decreases substantially, the loss of demand response resources during peak demand conditions could be substantial.
  • With limited snowpack, major California reservoirs are now at record low levels and have limited, if any, hydropower capacity. Innovative pumped water storage projects like Pacific Gas and Electric’s (PG&E’s) Helms System, which uses off-peak Diablo Canyon nuclear power to pump water up for day-time generation use, will be at risk.
  • Recent reports in media have suggested that many locations in California’s Central Valley are sinking as a result of ongoing water pumping from the underground aquifers by all types of commercial and agricultural businesses. Not only are residential, commercial, and agricultural wells going dry, but the land itself is subsiding. This has tremendous implications for California’s Peripheral Canal system and other longstanding canals that transport water north to south through the central valley. As subsidence occurs, it is entirely possible that cement canals will fracture, and major leaks will occur, further exacerbating the water loss problem.

As in many states, the electric transmission infrastructure in California is aging. It’s clear that California’s drought will have a significant effect on the electric power market as well, degrading demand response resources, electric demand for water pumping, and hydropower resources.


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