Can I lock in a fixed price if I'm on the Tarifa Transparente?

Yes, thanks to the Price Guardian. It's an optional add-on that lets you lock in a fixed price per kWh for a full billing cycle.

It can be activated during the first 7 days of each month and has an additional fee of €3.90/month, charged for the full month regardless of when it is activated.

If you'd prefer a permanently fixed price with no monthly management, you can also switch to the Tarifa Constante.