MARRAKECH, Morocco (Reuters) - U.S. commodities trader Gerald Group plans to increase production at its Sierra Leone iron mine to 7 million tonnes next year from 3 million tonnes now, Chief Executive Officer Craig Dean said on Thursday.

The expansion will require an investment of $300 million that will be raised through debt, Dean said in an interview with Reuters.

For this project, "We will need up to 35 megawatts of power. ...We will be the largest consumer of power in Sierra Leone," he said on the sidelines of a US-Africa business summit.

The project is 90% owned by Gerald Group and 10% by the Sierra Leone government.

The group is also planning to expand its footprint through high-tech metals, looking in particular at cobalt in the Democratic Republic of Congo, he said.

The company posted its highest profit in 60 years last year, and it expects that to continue this year, Dean said.

(Reporting by Ahmed Eljechtimi; Editing by Mark Porter)