The capacity of solid state drives (SSDs) has been advancing steadily on traditional spinning hard drives over the last few years, and drive manufacturers haven’t been certain how much longer spinning drives could remain in the lead. Western Digital just surprised the storage industry by announcing its upcoming Microwave Assisted Magnetic Recording (MAMR) technology, which could keep the price per gigabyte of spinning drives lower than SSDs for at least the next decade.

The odds are that your laptop (or even your desktop) is running on a SSD rather than a spinning drive. Some systems have a secondary spinning drive for bulk storage because they’re cheaper per gigabyte, but spinning drives can’t match the speed of an SSD. Even if your local data is on a zippy SSD, whatever you have in the cloud is living on big spinning hard drives. Data centers are constantly after higher capacity drives, and Western Digital thinks MAMR is the way to do it.

In MAMR, the magnetic write head is modified to also carry a tiny spin torque oscillator (STO) that generates microwaves with a frequency of 20-40GHz. This addition doesn’t require a complete redesign of the head, though. The microwaves lower the resistance of the underlying recording media, which in turn makes it easier to write bits on the platter. The result is higher density without a complete redesign of the drive’s internals.

If MAMR works out, it would most likely replace Heat Assisted Magnetic Recording (HAMR) and the next generation standard. With HAMR, a laser is used to heat the media and make it easier to write. So, the end result is similar to MAMR. However, repeatedly heating the hard drive platter to several hundred degrees would cause a reduction in longevity. The head design would also be completely different than current hard drives, which adds to the manufacturing complications.

MAMR doesn’t heat the recording medium at all, and the technology to make it work is invisible to the host machine. Not only would HAMR require completely new manufacturing techniques, but servers would also need new driver software to manage wear leveling caused by the rapid and repeated heating. WD claims that MAMR drives should easily match the lifespan of current drives.

Western Digital is talking about the possibility of 40TB enterprise hard drives using MAMR by 2025, which is a mind-boggling amount of storage. The first hard drives with MAMR technology could hit the market around 2019 or 2020.