Just in time for the back-to-school season, new laptops with extended battery life are hitting store shelves. What these laptops have in common are microprocessors that belong to a new family of Intel chips called Haswell. The chips consume less power than previous generations and promise a 50 percent boost in battery life for watching video. The improvements extend to word processing, Web surfing and other computing tasks as well.
Put another way, you can unplug your laptop in the morning and go a full day without a charge, with some breaks for meals, exercise and errands. The 13-inch (33-centimeter) MacBook Air, for instance, promises up to 12 hours of battery life. Three Windows machines I tried promise seven to nine hours. For students, that's a full day of cutting classes -- and more. For business travelers, that's a cross-country flight including delays.