Energy efficiency is a significant global issue today, and is expected to be even more important in the future. For the IT industry, concerns about affordable energy are playing out in data centers. Rising costs of energy -- along with limited availability of energy in some areas â€“ are forcing the IT industry to take a new approach in designing and managing data centers. Data centers have doubled their energy use in the past five years, while U.S. commercial electrical costs increased by 10 percent from 2005-2006. With continued projected increases in energy consumption, at some companies, the situation is critical. Gartner research firm estimates that 70 percent of the Global 1,000 -- the world's largest enterprises -- will need to modernize their data centers within the next five years.