BOSTON — The chairman of Spanish utility Iberdrola says his company’s U.S. subsidiaries are spending $10 billion on wind power and energy-related projects over the next few years, but he says political and regulatory uncertainties could stall future investments.

Ignacio Galan told The Associated Press today that companies investing in wind energy need predictability and stability because the projects can take years to reach fruition.

Galan’s company is the corporate parent of Central Maine Power, the state’s largest electric utility. It is also the second-largest wind power company in the U.S.

Galan is in New England for the groundbreaking Tuesday of the Maine utility’s $1.4 billion power grid upgrade, a project aimed at improving reliability and increasing capacity.