Andrew McCree, whose company includes 50 people at offices in Glengarnock, said: "There was already a cross-party consensus in the US that the country has to reduce its dependence on oil and get more energy-efficient.
"The Gulf of Mexico spill will have a major, major impact. It will probably mean a stronger political mandate to push farther and faster in this area (alternative energy]."
As a result McCree said it was "reasonable to assume that there's going to be continued strong growth in the US". The group, which revealed yesterday that annual pre-tax profits halved to 3.5m from 7.5m after exceptional items, advises the private and public sectors on implementing environmentally sustainable policies.
McCree said he expected the UK and European mainland markets to remain tough because of public-sector spending cuts. But he said AEA had anticipated this by taking 10 per cent off the UK cost base in the year, involving 60 redundancies.
He said: "I have been cautious about Europe for some time, almost getting a reputation as a miserable Scotsman for it. But we have already taken a lot of action so are well-placed. We knew there would be significant changes to the levels of government spending.
"We cannot predict how long this will go on for, but in the UK we are not dependent on any one contract, customer of big infrastructure project."