Do Solid State Drives Really Make Batter Life Longer?

It’s been a marketing pitch of solid state drive (SSD) makers that these storage devices, having no spinning parts like their hard disc counterparts, would help save on energy use, hence extending laptop battery life. Sure enough, those of use who use music players do notice that Flash-based players last longer than their micro-drive counterparts, like the ones that the full-size iPods use.

However, some simple tests have proven that the use of SSD may not necessarily lead to battery savings, or if any these would be marginal. According to ZDNet:

The maximum power difference between a flash drive and a 2.5″ disk is 3 watts. If you average about 3 hours battery life, a flash drive would save at most 9 watt hours (wh). That’s 29 minutes with a 55 wh battery. Less than 20 if it isn’t seeking constantly - and less than 10 minutes if the drive spends half its time in standby mode.

The biggest power sink in my notebook is the “everything else” that stays on when nothing is happening - 13 watts. Next is the CPU when it is busy. Then the display if you keep it above minimum brightness, the DVD/CD player and finally, just above Wi-Fi, a busy disk.

Flash drives have a real advantage in shock resistance over disks. But the performance is about the same as a disk, the power savings minimal and the cost disadvantage huge. They make the most sense for premium ultra-light notebooks with low power CPUs and small screens as well as hand-held devices.

This means there isn’t a very big difference. Most of your other laptop’s peripherals, such as the LCD screen, optical drive, and other things, might contribute more to battery drain, that the SSD alone will not compensate for.