Battery life is limited because the capacity drops with time, eventually requiring replacement after as little as a year. A new battery typically stores enough energy to run the laptop for three to five hours, depending on usage, configuration, and power management settings. Yet, as it ages, the battery's energy storage will dissipate progressively until it lasts only a few minutes. The battery is often easily replaceable and a higher capacity model may be obtained for longer charging and discharging time. Some laptops (specifically ultrabooks) do not have the usual removable battery and have to be brought to the service center of its manufacturer or a third-party laptop service center to have its battery replaced. Replacement batteries can also be expensive.