Industry minister Jose Manuel Soria penned the drastic measure in the face of a €24 billion deficit in the electricity sector. Subsidies to national coal generation are not affected.
The moratorium might severely damage the broader economy, according to Spanish wind association AEE, by threatening 30,000 jobs and €2.4 billion of annual exports.
There is also a risk that Spain may miss its goal of 33.75GW of wind capacity by 2020. It currently has just under 22GW.
Wind projects already approved on the national pre-allocation register are not affected by the moratorium.
However, AEE members calculate that of 2GW of registered projects still to be built, around half will not make the end-2012 deadline due to infrastructure and other delays.