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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 that dependence on solar power was to blame

for the country's worst ever blackout, as Prime Minister Pedro

Sanchez faced increasing pressure to explain what went wrong.

With life returning to normal after a blackout that halted

trains, shut airports and trapped Spaniards in lifts, Sanchez's

opponents pointed the finger at low investment in a system that

relies heavily on intermittent solar and wind.

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 and private companies.

REE, which is headed by former Socialist minister Beatriz

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

separate incidents in substations in southwestern Spain, but

says it is still 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. She was not considering

resigning, she added.

In a separate interview she said the government had given

power companies a deadline to provide data by Wednesday

afternoon that would help explain what had gone wrong.

'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 cyberattack,

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 fault was

not with their operations 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 (CSIC), 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 isn't enough.