World : Scientists and utilities reconsider the grid in the age of renewables

Idaho Falls Power General Manager Jackie Flowers walked on the stage before a public forum several weeks ago, and the lights went off.

Attendees seated at tables behind plates and glasses of lemonade looked around in dark confusion. Seconds later, overhead bulbs lit up again while Flowers stood with a microphone.

“Nothing like an interruption in power to make you appreciate your electric service,” she said to the laughing audience. “We take it for granted, and the only time you think about it is when it goes out.”

Electricity makes numerous stops before powering a lightbulb. It’s created by a plant or other generation source — possibly a wind turbine or solar panel — before traveling through transmission lines and transformers, finally ending up at a house or business.

Collectively, the spiderweb of infrastructure is referred to as the electrical grid. Though it surrounds people’s lives, the grid is largely absent from their minds. It either works, or is an inconvenience.

And lately, it’s become more inconvenient.

Grid disruptions increasingly common

Between 2000 and 2014, the five-year annual average of power outages in the U.S. doubled every five years, according to Inside Energy, a collaborative public journalism initiative. There were 174 grid disruptions in 2013, six times more than in 2000, when there were 30.

Outages in Idaho Falls actually have become less frequent, largely due to the installation of transmission line squirrel guards — rodents are the bane of utilities — and more proactive tree trimming, Flowers said.

Still, disturbances in greater eastern Idaho have increased, often due to equipment failure.

As the complexion of the aging grid changes — partially due to intermittent, renewable energy sources — utilities are seeking ways to stabilize their equipment and prevent angry phone calls from customers.

Idaho Falls Power has the unique geographic opportunity to collaborate with nearby Idaho National Laboratory, where researchers have studied the electrical grid for several years. Together, they’re looking for ways to improve the grid in light of changing energy consumer habits and technologies.

“The grids of yesterday aren’t the same as the grid of today, or of the future,” said Rob Hovsapian, INL’s Power and Energy Systems department manager. “Every aspect of our research is how to provide stability and resiliency to the grid.”

‘Thinking’

Energy generation has become erratic since the grid’s coal-powered 20th century maturation.

Coal, natural gas and nuclear plants are generally predictable producers of power. Utilities can run them for set amounts of time to create set amounts of energy. Renewables, however, are powered at the whim of external circumstance.

Nature doesn’t always match consumers’ energy needs; the wind may not blow when a large percent of the population returns home from work at 5 p.m., a peak energy usage time.

That’s problematic because the grid doesn’t have a widespread storage system. Essentially, energy must be used the instant it’s generated, which can create headaches for people such as Flowers.

Too much input — maybe from a sudden windstorm combined with a conventional nuclear plant that takes time to ramp up or down — could blow out a substation. Too little energy, meanwhile, may result in an outage.

“Our primary focus was always to keep the lights on and the heat running, but utilities across the country are thinking about resiliency in different ways,” Flowers said. “Whereas before it was fixing a problem when the power goes out, now it’s thinking about how to use certain amounts of intermittent energy, and if that goes away, how fast can we recover with other generation sources.”

‘Power is infused everywhere’

Similar issues emerge on the customer end of the grid.

Aaron Wilson installed solar panels on his previous Idaho Falls home in 2014 as an investment and method to increase self-sufficiency.

Idaho Falls Power is a public utility, which means its rates are dictated by federal guidelines. At about 6 cents per kilowatt hour, rates are much lower than the national average of about 13 cents per kilowatt hour.

Though electricity is cheap in Idaho Falls and the area doesn’t get nearly as much sun as southern California or Arizona, Wilson realized solar panels pencil out financially.

“The math works out at this point, given how terrible bonds and other investments are. I’m surprised it hasn’t caught on more than it already has, given how cost effective it is,” he said. “I’m a customer, all I care about is if it improves my system and saves me money.”

Wilson was one of the first Idaho Falls homeowners to purchase solar panels. There still aren’t many: a total of eight residential and four commercial users.

But, the price to install solar systems is steadily dropping — 10.6 percent over the last year, according to the Wall Street Journal — while adoption rates are quickly increasing, with 25 percent industry growth in 2015.

If adoption rates continue to grow — along with other grid-related technologies, such as electric cars — utilities face the same concerns that come from commercial wind and solar farms. Additional, often unpredictable variables threaten stability.

“As you have more rooftop solar at the customer location, the grid still has to move power. It just may not be one direction now; power is infused everywhere,” Flowers said. “Certainly it’s changing how we think about and stretch the capabilities of the grid. We’re seeing investment not in generation resources, but in technology to help shape those intermittent resources.”

A worldwide grid?

Some of that technology is being developed at INL. Last month, Hovsapian’s team and seven other government and academia labs, including in Italy and Germany, simulated a transcontinental electric grid dubbed the “Real-Time Super Lab.”

Several dozen employees gathered at INL’s primary grid research lab in Idaho Falls surrounded by computers, monitors, and servers, while scientists from other labs around the world teleconferenced in.

The scientists at each lab simulated the infrastructure that would exist for a real grid, including generation sources and energy customers, then connected their grids to make one piece of infrastructure spanning from Washington state to Germany.

Afterward, they tested it with various real-world scenarios.

If a German wind farm generates too much power to use locally, could an Italian utility divert power and ramp down its natural gas plant? If thousands of people charge their electrical vehicles after work in New Mexico and leave a deficit in local generation sources, could a large storage system in Colorado make up the difference?

The simulation’s connected grids became more stable because they could more efficiently and flexibly use their collective resources. Additionally, simulated equipment issues with one grid could be diagnosed more quickly with input from the other connected grids.

Hovsapian said the Super Lab concept was inspired by the first telecommunications cables to go transcontinental in the 19th century.

“We eventually went more regional, then national and now it’s global. We anticipate that the power grid will have a similar evolution,” he said. “We’re already seeing the evolution of connectivity between different countries in Europe and Norway. There’s more high voltage connectivity in southeast Asia.”

Currently, utilities use renewables to supplement conventional plants. Greater global connectivity could make renewables more viable as a “baseload” resource, in the process bolstering grid resiliency.

“You can move energy from where the sun is shining in Europe to where it isn’t in the U.S.,” Hovsapian said. “Or if the wind is blowing in the southern hemisphere, and it’s needed in the north, you can better manage those seasonal changes by taking advantage of connectivity.”

Following what he sees as a successful test, Hovsapian expects more labs and universities across the world to band together, write proposals and build on the Super Lab concept while researching additional ways to increase stability in coming decades.

 

Source : http://magicvalley.com/news/scientists-and-utilities-reconsider-the-grid-in-the-age-of/article_f42c72ed-0955-5a38-b9f0-17ac3128a6c9.html

SMART GRID Bulletin November 2017


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