2. Go for rates which vary according to the time
They are the best way to save for almost every household. Including yours if you are able to concentrate at least a third of your consumption in off-peak hours.
We all know that energy is cheaper when there is less demand (for example, at night). But we are not aware that, in general and without thinking, we usually consume 50% of all energy during off-peak hours.
Thus, switching to a tariff with hourly discrimination can help us save many euros a year on our electricity bill without any effort at all. Whether you are in the free market or in the regulated market.
In the regulated market, the PVPC Tariff, it is not possible to know what the price of energy will be next week, but with this tool, you can check tomorrow's price. And while you're there, check the big price difference between peak hours (from 12.00 to 22.00 in winter and from 13.00 to 23.00 in summer); and the off-peak cheaper ones (from 22.00 to 12.00 in winter and from 23.00 to 13.00 in summer).
The free market offers you all kinds of à-la-carte rates in which you decide which hours are the cheap hours. But the big news is about rates like the Tempo Happy Rate where you choose a few hours in which consumption is free.