"The Windows Vista Aero theme and components which implement it can use more resources than previous versions of the operating system," Microsoft product manager Mike Burk said in a statement.
Microsoft claims that the current version of Vista delivers less battery life than Windows XP, at a time where we are increasingly demanding longer battery life in our mobile computers. Just when hardware manufacturers were promising notebooks with longer battery life, now we seem to be moving back a step with a more power hungry OS. Microsoft has, of course, promised to deal with this before Vista ships. They claim to be working with PC makers to ensure that systems are better able to handle the new OS.
"As a result, the impact on battery life is small," Burk said.