April 24, 2014
NASA Space Weather Project To Utilize High-Voltage Transmission Lines And iPads
April Flowers for redOrbit.com - Your Universe Onlinegeomagnetically induced currents, or GICs.
"This is the first time we have used the U.S. high-voltage power transmission system as a science tool to map large-scale GICs," Pulkkinen said in a recent NASA statement. "This application will allow unprecedented, game-changing data gathering over a wide range of spatial and temporal scales."
This data — especially if the planned nationwide study evolves — will have important implications for the power industry. It should also allow heliophysicists to learn more about the conditions in Earth's upper atmosphere that lead to the generation of GICs during severe space weather events by reverse engineering the data. Pulkkinen is currently developing the computer algorithms necessary to extract the data for scientific research. "Not only will this benefit the utility industry, it also benefits science," he said.
A coronal mass ejection (CME) is a solar event where a giant bubble of charged particles is unleashed from the sun. This bubble can carry up to 10 billion tons of matter and accelerate up to several million miles per hour. GICs typically occur one-to-three days after a CME, when the matter impacts the Earth's magnetosphere causing electromagnetic fluctuations. These fluctuations cause geomagnetic storms on Earth, increasing electric currents that, in turn, drive the fluctuations in Earth’s magnetic field near the ground. Any large scale conductive structure — such as power lines, oil and gas pipelines, undersea communication cables, telephone and telegraph networks, and railways — can conduct the surface currents created by the storms.
[ Watch the Video: Top Space Weather Questions ]
One of the largest disturbances of the 20th century, the great magnetic storm of March 1989 is an extreme example of a GIC event. During this event, rapid variations in the geomagnetic field created intensely induced electrical fields at the planet's surface. In turn, this field pushed electrical currents through the Canadian Hydro-Quebec power grid. The transmission system was collapsed by the excess current, leading to a loss of electric power to more than six million people.
The US Geological Survey estimates that if that same blackout had occurred in the Northeastern US, the economic impact might have exceeded $10 billion. That estimate does not include the devastating effect on emergency services and the reduction in public safety.
A wide range of damaging effects, from disrupting communications and navigation systems, to damaging satellite instrumentation, to potentially corroding pipeline steel, can be the results of space weather events. At the moment, the potential impact on the nation's electric grid is of the highest concern. "It's the hottest topic out there right now," Pulkkinen said "We need to better understand how these events affect the U.S. power grid." Federal Energy Regulatory Commission is now developing standards to mitigate the GIC threat, according to Pulkkinen.
Pulkkinen and his team are creating three substations that will be equipped with commercially available magnetometers. The magnetometers will provide precise measurements of the variable magnetic fields associated with GICs. Goddard engineer Todd Bonalsky created a protective, watertight housing unit for the magnetometers. Two of the units will be buried directly beneath Dominion Virginia Powers high-voltage lines, and the third will be buried one-to-two miles away to provide reference measurements.
"In essence, we're tapping into a very large antenna," Pulkkinen said. "The high-voltage lines are the antennae. During solar storms, violent changes in the electric current occur in near space, which then are sensed by the transmission lines."
Another iRAD-developed technology developed by Carl Hostetter and Troy Adams of Goddard, LabNotes, will be used to command and control the substations. The iPad application will time tag and geo-locate data from the magnetometers, deliver it to a server through a cellular network. LabNotes will send one sample per second, as well as monitor the data, with the ability to send a text message should an event warrant human attention.
"Now that everyone is walking around with this type of computer, which is more powerful than some supercomputers of 15 years ago, we thought we may as well use it for scientific purposes," Hostetter said. He said the relatively small size and low-power consumption of the iPad Mini makes it ideal for science gathering. Although this project is the first to actually use the LabNotes application, Hostetter said the technology has garnered the interest of a number of other research teams, including one focusing on agricultural needs in Africa.
The project is starting small, with the goal of making the equipment as inexpensive and versatile as possible. The end game will be to create a nationwide network of substations. "We envision that after a one-to-two-year pilot phase, long-term funding from a multi-agency collaboration and public-private partnerships will make this happen."
"Impacts to the nation's power grid are currently the highest space-weather concern in the U.S.," he added. Pulkkinen said such data would help define the most effective techniques for mitigating GIC threats and inform the federal regulations that are already on the horizon.