Despite the central government's freeze on new renewables capacity since 2012, Spanish wind saved the electricity system €15.7 billion 2012-2015, inclusive, according to a study by consulting firm Deloitte.
The figure translates into a saving of €227 for the average domestic electricity bill payer over the period.
The savings — based on data from the national grid operator REE and electricity market operator OMIE — are due to wind pushing conventional power off the electricity system.
Fuel costs largely determine the price of electricity on the wholesale market. Wind's fuel costs are zero, so the more of it entering the system, the lower the wholesale price.
Deloitte said wind produced additional savings of €657 million by offsetting 106 million tonnes of CO2 emissions, as well as avoiding the import of 40 million tons of oil worth over €9 billion.
Spanish wind association AEE is touting Deloitte's findings to pressure the government in its end-year review of subsidies for wind.
Those subsidies, introduced in 2013, ended the electricity price support model, which had driven Spanish wind capacity to exceed 23GW by end-2012; the year when new capacity ground to a halt.
Since 2013, the new subsidy has paid existing wind capacity €630 million below the government's expectations, according to AEE.