The utility company also said EBITDA fell 63% for renewables in its home country.
Last year, the cash-strapped Spanish government ended existing feed-in tariffs for renewables and replaced them with a 7.5% remuneration on profits.
Iberdrola said wind projects were worse affected by the changes rather than other renewable technologies such as solar.
The company's UK arm saw EBITDA increase 32% attributed to an increase in production and a 28% increase in the United States.
Latin American earnings rose 52% thanks to increased capacity in Mexico but this was offset by a 40% loss elsewhere following the sale of Polish wind projects in 2013.
As a whole, Iberdrola's net earnings increased 8.4% in the first quarter to EUR 952.6 million but EBITDA was down 0.3% to EUR 2.1 billion.