China, India and Brazil will more than double their energy use and greenhouse gas emissions by 2030 if they fail to improve energy efficiency substantially, the World Bank said in a book released yesterday.

The book, titled Financing Energy Efficiency: Lessons from Brazil, China, India, and Beyond, dissects the energy efficiency terrain and discusses the obstacles for getting the right incentives to encourage more investment in efforts to save energy.

It also finds that cost-effective retrofits could reduce these countries' energy use by at least 25 percent and advanced technologies could reduce their energy demand growth by 2030 by at least 10 percent and reduce projected CO2 emission growth by 16 percent

"What we found is enormous untapped potential - especially in Brazil, China and India," said Bob Taylor, a key author of the book and World Bank energy economist. "Plenty of good solutions can work as long as the financing and investment environment is in place and there's plenty of commitment from policymakers."

China, India and Brazil, three of the four BRIC countries apart from Russia, are the world's top 10 energy consumers and are home to 40 percent of the world's population. The three now account for more than half of all energy demand by developing countries.

The World Bank says they will be responsible for 42 percent of growth in energy demand worldwide by 2030.

According to the book, energy efficiency is critical in the three countries "for reasons of energy supply security, economic competitiveness, improvement in livelihoods and environmental sustainability".

Presently, the main obstacles to getting energy efficiency off the ground are inadequate organizational and institutional systems as well as access to necessary funds, says the book.