Spain’s nationwide blackout this week has put a spotlight on potential vulnerabilities in its system that may offer warnings to other countries, as rising electrification and clean energy sources place new demands on power grids around the world.

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.

The blackout across Spain and Portugal knocked out communications and transport systems, shut down industry and offices and brought commerce to a virtual standstill. The blackout could have shaved 1.6 billion euros ($1.82 billion), or 0.1%, off GDP, Spain's business lobby estimated.