There are two systems in Spain, the regulated and the unregulated. If you take out a contract with Iberdrola (or other company) you can opt for several plans. There is the day/night plan where electricity is cheaper from midnight to 1pm (11pm to noon in the Winter) or the choose your own hours where you can have any eight hours (not in succession but in 1 hour slots if you want, we have 8 to 11 am and 5 to 10pm as our cheap hours). The advantage then is that the rates are fixed for as long as your contract is in existence. Of course, if electricity goes down you will not get the benefits but at only just over 8 cents a kwh in off peak and just 19 cents for non peak periods that won't happen for a long time).
With the unregulated you are at the mercy of the ups and downs in prices which have been horrendous in the last year. You would benefit if prices went down but, again, that's not happening, especially at the rates we are currntly paying. Iberdrola (or whoever your supplier is) would put you on the regualated rates but would have to tell you what they are so you could make your mind up if you want to go down that route. They are currenlty charging 14 cents on the day night plan for cheaper hours and 23 cents for peak periods so you could compare that to what you are paying now. These figures will change, of course.
With these plans, even the contracted charge for the power provided changes during non peak periods from 9 cents per Kw contracted down to a third of a cent in contracted hours so that saves a lot.
If you leave your aircon or heating on all night and use things like dishwashers and washing machines in the morning then the day/night tariff is ideal.
We went to the 8 hours a day plan. We were paying around 100 euro a month but that has dropped to under 50. July and August more expensive because the aircon is on a lot. Even so, last month bill was 64.64 for permanent usage and they keep sending a message that the bills will not rise despite the increased costs .
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