Pre-tax earnings reached €428.3 million in the first three months of 2015. Most of this came from outside of Spain, as Iberdrola saw renewable energy production fall 14.7% in its home nation.
The €149.2 million of earnings in Spain was helped by a climb in prices from "extraordinarily low levels" in 2014.
The low generation in Spain was offset by higher figures elsewhere including in the UK. In October, the 389MW West of Duddon Sands project in the Irish Sea was brought online. It helped boost Iberdrola's production in the UK by 14.7%.
Group chairman Ignacio Galan said the project has been operating at a 55% load factor, helping to boost earnings. West of Duddon Sands was jointly developed and co-owned with Dong Energy.
Iberdrola also recorded higher output from its renewable projects in Mexico and Brazil. There was a 13.2% fall in production in the US.
Output is expected to increase outside of Spain this year. Iberdrola has 450MW of wind projects in the UK that are being built, or due to begin construction, this year. It is also developing the 350MW Wikinger offshore project in Germany.