Spain blackout sparks renewables backlash but experts flag batteries, grid resilience

As Spain continues to investigate the causes of the power outage that plunged the country into total blackout on April 28th, the event of unprecedented scale has sparked a backlash against renewables, with some saying that the country’s high reliance on solar and wind for power generation is the main cause of the incident. However, experts are pointing at the need to ramp up batteries and grid resilience.

The blackout — which impacted all of Spain as well as parts of Portugal and France — was preceded by two separate incidents of power generation loss, leading to a cascade effect which led to most generation capacity disconnecting and to power links between Spain and France shutting down, grid operator Red Electrica said, according to media reports.

Data from Red Electrica shows that solar and wind together accounted for around 70% of electricity generation at around 12.30pm on April 28th. Nuclear and CCGT plants were covering around 11% and 5% respectively.

But between 12.30 and 12.35, available solar generation capacity plummeted from 18 GW to just 8 GW, the data shows.

Red Electrica did not respond to a request for comment.

In the hours preceding the blackout, oscillations in grid frequency were noted in Spain.

However, “a simplistic ‘it was renewables’ view is almost certainly wrong,” Adam Bell, director of strategy at UK consultancy Stonehaven and former head of strategy at the UK Department for Business, Energy and Industrial Strategy (BEIS), told Gas Outlook.

“What is likely is that regardless of the cause of the initial two frequency events a number of factors contributed to the subsequent frequency cascade, including protection settings on generation assets being set too conservatively and causing generators to drop off early, as well as questions around whether grid topography contributed to the result,” such as “whether inertia available to the system was too far away from a mass of generation with grid-following inverters,” he said.

Grid inertia allows it to maintain a steady frequency, and is provided by energy stored in the rotating masses of large generation assets such as conventional gas-fired power plants.

By being ‘asynchronous’ resources, renewable sources do not provide grid inertia and a high penetration of renewables in a system is often cited as one major driver for grid instability.

Nonetheless, in a LinkedIn post Bell noted that the Spanish system could still rely on other sources of inertia such as “nuclear, hydro, and solar thermal” on April 28th.

“A lack of inertia was therefore not the main driver for the blackout… Indeed, post the frequency event no fossil generation remained online – but wind, solar and hydro did.”

“For the UK, this is a reminder to continue to drive the adoption of synthetic inertia from devices like batteries, which can provide a similar service through power electronics rather than spinning metal,” he added.

Meanwhile, the Spanish government excluded the theory that renewables alone were the cause for the blackout.

And while the cyberattack cause was also ruled out by Red Electrica, the Spanish High Court said it will investigate all possible causes.

Initial analysis indicates the possibility of the incident being due to a cyberattack is “very low” Massimo Rocca, of the European Energy Information Sharing and Analysis Centre, told Gas Outlook. The centre is a network of utilities, academia, governmental and non-profit organisations aimed at sharing information on cyber security and cyber resilience.

The event highlighted a need to strengthen controls over renewable generation resilience and to “include programmable generation in the mix,” to provide grid stability in case of blackouts, among other things, he said.

He added another aspect was that of interconnections between countries, a long-term goal in Europe — all EU countries should have in place internal and cross border power lines capable of importing or exporting 15% of their national generation capacity.by 2030 under current targets — which would help support resilience, but that is somewhat discouraged by the “current geopolitical climate.”

‘Island’ grids

Lack of interconnection as a contributing factor to Spain’s vulnerability was also highlighted by analysts at price reporting agency Montel.

“Spain’s countrywide blackout on Monday has demonstrated the vulnerability of so-called ‘island’ and peninsular grids, despite international improvements in redundancy and forecasting capabilities in recent years,” Montel Analytics director, Jean-Paul Harreman, said in a statement.

While the outage was an “unprecedented event in modern energy markets”, the blackout occurring in Spain and Portugal is “not particularly surprising”, as “countries that are on the edge of, and more isolated from, the synchronous European grid tend to more easily see grid frequency deviations.”

“In island systems like GB and Ireland, or peninsular systems like Italy and Spain, the AC synchronous interconnectivity with other countries is much lower, leading to a more vulnerable grid as flexibility and resilience has to mostly come from the inside,” he said.

By contrast, a country like Germany is “surrounded by many other countries and connected with AC connections, in which assets operate that provide resilience to the grid frequency,” which needs to be kept at 50 Hz at all times to prevent blackout.

“Whenever there is a deviation due to a power plant outage… There is sufficient flexible capacity to ‘catch’ the frequency before it goes ‘out of bounds’,” he said. “This buys time to bring up other generation capacity to fill the gaps or take other measures.”

He noted that a blackout of this scale has not been seen since the 2003 Great Italian blackout, or the Turkish blackout of 2015.

(Writing by Beatrice Bedeschi; editing by Sophie Davies)