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Sanchez under pressure to provide explanation for blackout

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Opposition calls for independent investigation

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Grid operator accused of failure to invest in system

upgrade

MADRID, April 30 (Reuters) - Spain's grid operator

denied on Wednesday dependence on solar power was to blame for

the country's worst blackout, while Prime Minister Pedro Sanchez

came under increasing pressure to explain what went wrong.

With life returning to normal after a power outage that

halted trains, shut airports and trapped people in lifts,

Sanchez's opponents pointed the finger at low investment in a

system that increasingly relies on intermittent solar and wind

power.

Sanchez has announced a government investigation and said he

was seeking answers from private energy companies that feed

power into the grid. He also said he has not ruled out a cyber

attack, although this has been dismissed by part-state-owned

grid operator REE.

Spain's authorities are still dealing with the political

fall-out from deadly floods in the east and south of the country

that killed more than 220 people.

REE, which is headed by former Socialist minister Beatriz

Corredor, has narrowed down the source of the outage to two

separate incidents of loss of generation in substations in

southwestern Spain, but says it has yet to identify their exact

location and that it is too early to explain what caused them.

In an interview with Cadena SER radio, Corredor said on

Wednesday it was wrong to blame the outage on Spain's high share

of renewable energy.

"These technologies are already stable and they have systems

that allow them to operate as a conventional generation system

without any safety issues," she said, adding she was not

considering resigning.

Just before the system crashed, solar energy accounted for

53% of electricity production, wind for almost 11% and nuclear

and gas for 15%, according to REE data.

Energy Minister Sara Aagesen said the government had given

power companies a deadline of late on Wednesday to provide data

for "every millisecond during those five seconds" when the

system on Monday lost 15GW of generation, equivalent to 60% of

demand, triggering a disconnection from the rest of Europe.

'MALFUNCTIONING OF REE'

Political opponents said Sanchez was taking too long to

explain the blackout, and suggested he was covering up for

failings at REE.

"Since REE has ruled out the possibility of a cyber attack,

we can only point to the malfunctioning of REE, which has state

investment and therefore its leaders are appointed by the

government," Miguel Tellado, a parliamentary spokesperson for

the opposition conservative People's Party, said in an interview

on RTVE.

He called for an independent investigation to be conducted

by Spain's parliament rather than the government probe Sanchez

has announced.

Spain's government said it had asked private energy

companies for "maximum collaboration and transparency" to help

identify the cause of the outage.

Ignacio Sanchez Galan, executive chairman of Spain's largest

energy company Iberdrola, said on Wednesday that the company's

operations were not at fault and it was REE that should clarify

the reasons for the blackout.

Antonio Turiel, an energy expert at the state-owned Spanish

National Research Council, told Onda Vasca radio station on

Tuesday that the fundamental problem was the grid's instability.

"A lot of renewable energy has been integrated without the

responsive stabilisation systems that should have been in

place," he said, adding that vulnerabilities stemmed from "the

unplanned and haphazard integration of a host of renewable

systems".

The government expects private and public investment of some

52 billion euros through 2030 to upgrade the power grid so it

can handle the surge in demand from data centres and electric

vehicles. Aelec, the utility lobby, has said that is not enough.

Jordi Sevilla, REE's chair until 2020, wrote in an opinion

piece in Cinco Dias newspaper that the government was moving too

fast to decommission nuclear power plants that can provide

stable generation to offset the peaks and troughs of

intermittent renewable energy.

The government's plan for investing in the grid "was planned

from an office, with too much renewable messianism and turning a

deaf ear to the technical problems associated with such an

important change in Spain's energy mix," he said.

(Reporting by David Latona, Pietro Lombardi and Aislinn Laing

in Madrid; Writing by Charlie Devereux; Editing by Peter Graff

and Barbara lewis)