Wind Power

Renewables find success in ‘black start’ experiment

Renewables find success in ‘black start’ experiment

Have you ever thought about what would happen if a power station failed? Without electricity to bring itself back online, it would be near impossible for a station to begin operating again, like trying to set fire to paper without a flame.

This scenario would quickly lead to widespread chaos, with hospitals and schools plunged into darkness, refrigeration, and sanitation seriously hampered and transport systems brought to a standstill.

For these reasons (and many, many more), governments and electricity networks often have complex and rigorous plans in place to bring dead power stations back online at the earliest. 

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These procedures are known as ‘black start’ plans and they are rarely necessary but when they are, the backup plans need to be dependable.

For the most part, however, black start plans are outdated. 

Commonly, black start methods include open-cycle gas turbines or diesel generators. The theory is that by starting small, an entire country could be brought back online relatively quickly using the following process:

  1. A battery starts a small diesel generator installed in a hydroelectric generating station. The generator is used to bring the generating station into operation.
  2. Key transmission lines between the station and other areas are energized.
  3. The power from the station is used to start one of the nuclear/fossil-fuel-fired baseload plants.
  4. The power from the baseload plant is used to restart all of the other power plants in the system.

However, as Venezuela discovered in 2019, and North America discovered back in 2003, these procedures don’t always work. Diesel generators can fail or contain too little power to be effective. And if that happens, you can’t get past step one.

The last American black start incident arose from what should’ve been a manageable local blackout. But human error and software bugs led to a cascaded collapse that affected fifty-five million people throughout the Northeastern and Midwestern United States alongside the Canadian province of Ontario. 

Clearly, such events must be prevented at all costs.

A global breakthrough

Happily, renewable energy sources have played a role in restarting Great Britain’s electricity system after a successful world-first trial.

An experiment in southwest Scotland saw a hydro generator connected to the distribution network self-start, energize the local transmission and distribution network, and power up wind turbines on two wind farms within an isolated test network.

The UK has never needed to test its black start plans but national security depends on the continuity of power so trials like these provide assurance that in the worst-case scenario, Britain can restore itself to full power rapidly.

Having the ability to light up blacked-out grids is even more pressing given heightened cybersecurity vigilance in these politically fraught times. 

The trial was so successful that it quickly established itself as a blueprint for firing up the UK-wide electricity system in the event of a shutdown.

The research, funded by Ofgem (the UK Government’s energy regulator) is part of a three-year ‘ReStart’ initiative that will use solar, wind, and hydro to restart the grid.

The Scottish experiment performed perfectly and quickly established a stable ‘power island’ by using the hydro-generator as an ‘anchor’ to self-start and power the local network. This then powered multiple turbines at Glenchamber and North Rhins wind farms, immediately proving the viability of this approach in a real emergency.

Industry commentators have been quick to praise the team behind the research. Ruth Chapman, MD of Dulas stated that, “yet again, renewables have proven themselves to be the clear solution to a problem that threatens power stability. It’s imperative that the findings of this research be deployed on a national scale at the earliest.” Project Lead, Peter Chandler agreed, stating that he hopes that “the concept will be further proven and lead to the adoption of a DRZC [Distribution Restoration Zone Controller] in the near future. 

This research is embryonic but it’s easy to see that 1) renewables have demonstrated their viability in a black start scenario and that 2) this research has global application.

I’m sure the residents of Venezuela and Northeastern America would agree!