The phrase "economic powerhouse" refers to a country or region that has a strong and influential economy. It means that the country or region is highly productive, wealthy, and has significant control over global markets. Full definition
If we are to keep our place as a true economic powerhouse, we must put our skilled labour force first. (social.hays.com)
Mr. Obama is appearing to say that the wealthy countries that build the existing human - generated greenhouse blanket do owe a climate debt, of sorts, to the poorest countries in the world, but not — if I read this right — to China and the other emerging economic powerhouses of the world. (dotearth.blogs.nytimes.com)
Specifically, the United States, Japan, and some other developed countries refused to commit to reductions until developing countries, as well as economic powerhouses like China and Brazil, made commitments of their own. (anthropozine.com)