Published on September 29th, 2014 | by Joshua S Hill0
Power Blackout Management Research Could Benefit Renewable Energy Integration
September 29th, 2014 by Joshua S Hill
A researcher from the US Department of Energy’s Oak Ridge National Laboratory who has been investigating how to better manage and track electrical power blackouts may also have developed a way to better integrate renewable energy into the power grid.
Travis Smith and fellow R&D staff members at the Oak Ridge National Laboratory (ORNL) Power and Energy Systems Group have been developing tools that will improve grid protection operation analysis and prediction that can work under different scenarios, and not rely on static simulations that fail to take into account real-time dynamics of the grid.
“We’re integrating existing tools to do an even better job at what they already do,” Smith said. “We eventually want to feed real measurements from the grid into the model, which for utilities means a faster response time because they can plan for individual scenarios.”
These tools could also eventually help protect against influxes of renewable energy sources, a vital learning step if renewable energy is to become the mainstay we need it to become.
Power Blackout Management
“When protection engineers look at the grid, they are studying it under static conditions,” Smith said. “So they simulate a fault to see what happens, but that simulation is not taking into account real-time dynamics on the grid.”
These static simulations are necessary, because in a majority of cases, grid protection relies on automated “dumb” devices installed on transmission lines and substations. These devices will trip a switch and shut off local power if a drop in voltage is detected, or some other disturbance. However, there is no feed back to the utility company to identify the when, why, where, or how of why the switch was tripped.
As the ORNL press release states:
In the past, utility engineers have used static models of local electric grids to aim for single-contingency, worst-case scenario protection strategies rather than dynamic, real-time solutions to a unique grid disturbance.
“Technicians often have to physically go to the substation and pull out a data file to understand what happened,” Smith added. Which helps explain why massive blackouts can happen, and are so feared — they spend hours trying to work out the initial fault, before they are ever able to determine how to stem the tide of.
South Africa’s Own Blackout Issues
Such tools are unlikely to help South Africa, however, who are currently facing a dangerous level of energy undersupply. According to Bloomberg, the country has been facing a shortage of energy supplies for years now, is well behind on construction of new power plants and funding, and may be five years away from being able to guarantee the power is always on.
“Eskom is in dire straits,” said Anne Fruhauf, southern Africa analyst at New York-based risk adviser Teneo Intelligence. Electricity shortages pose the biggest risk to the country’s economy, and in the long term “South Africa cannot dream of reaching a higher-growth path without an increase in baseload capacity.”
Eskon was once an African energy giant, supplying energy to neighbouring countries as well as to home. Now, however, they are running decades-old power plants unable to keep up with the increased demand, forcing the utility to regularly ask customers to conserve energy, or even simply initiating managed blackouts.
The Power of Blackouts
In the end, situations like South Africa’s energy supply could be an issue many countries face going forward. India has recently had to sign a deal to increase nuclear energy to keep up with their exploding population, while China has initiated one of the most impressive renewable energy expansion projects seen — topping solar PV manufacturing and capacity charts over the last year.
With the integration of more and more renewable energy into electrical grids, tools such as those being developed by the Oak Ridge National Laboratory will end up proving invaluable. Without “smarter” electrical grids, not only will old power plants and transmission technology begin to negatively affect national energy distribution, but integrating newer energy generation — energy generation that, in the case of wind and solar, is inherently sporadic and temperamental — will simply compound the problem, to the extent that the sporadic input of renewable energy may begin to cause national grid blackouts.
“Once you have a faster, smarter grid, you need protection for a faster, smarter grid,” said Travis Smith. “I’m working with computer scientists at ORNL to see if we can push the model to run faster than real-time speeds so we can predict what will happen before it happens.”
And while Smith believes he may be “the only person in the world using this kind of program right now,” he predicts that utility companies the world over will soon be adopting such real-time protection analysis in the next few years.
It will happen “soon, if we see a large blackout,” Smith said. “We’ll zoom into the model using EMT (Electro Magnetic Transients), see what is happening among protective relays, and run higher resolution time step simulations to solve the problem before it gets out of hand.”