Western Digital produce some great quality drives: from massive 22TB hard drives to super-fast NVMe SSDs. They also make a drive that sounds fairly eco-friendly: the WD Green range. Unfortunately using this drive in your Synology NAS can have some big consequences. Here’s why.

What Makes The WD Green Drives ‘Eco-Friendly’

A WD Green hard drive

WD Green drives claim to be “earth-friendly” and “energy efficient”, using a range of power saving techniques to use less than 4 watts of energy during read/write cycles – compared to WD Blue HDDs that often use above 8 watts in a like-for-like test.

Green drives achieve this low-energy feat in a few different ways:

  • The drives will ‘shut down’ (go into a low power mode) when nothing is accessing them. They can then rapidly start back up when something needs to access their data again.
  • They use “IntelliPower” technology to work out the most efficient combination of drive spin speeds, caching and transfer rates in order to balance both performance speeds and power usage. Buzz words aside, this means that – compared to other hard drives and SSDs – WD Green drives will run slightly slower if this means that a decent amount of electricity (30-40%) can be saved.
  • They also contain internal mechanical features that allow Green hard drives to “reduce aerodynamic drag” on their drive heads. This lowers energy consumption, but it also leads to less load counts than standard drives – basically meaning that WD Green drives have a lower lifespan.

With soaring energy bills and a continued drive for households and companies to lower their electric consumption, the WD Green drives would seem like a natural choice – right?

Why WD Green Drives Should Be Avoided In Your NAS

A Synology NAS with a WD Blue drive and the text yes; then a WD Green drive and the text no

A high quality NAS – such as one from Synology – comes with a bunch of features and technology that balances good transfer speeds and power consumption. However a NAS will also ‘expect’ the data drives to be accessible, especially because drives might be running on a RAID array (where drive uptime is crucial for monitoring drive health).

Therefore if you run WD Green drives that frequently shutdown (or appear offline) to save on energy, this can cause problems with your Synology NAS and/or its RAID array.

In the best case, your NAS’ performance (including file transfer speeds) might be reduced. However in the worst case, you might start to experience data corruption – especially if your RAID array gets into a bad state after assuming that one (or more) of the drives is corrupted.

That might sound like scare mongering on my part, especially because one user on Reddit accidentally used Green drives in their NAS for many years – without having any problems. But in general, WD Green drives are designed for additional storage drives. They are not designed to be your primary data storage solution, especially if you were planning to run RAID 0 for performance reasons.

RAID Tips: The different configurations of RAID is a fairly wide topic which I won’t cover here, but NAS users sometimes use RAID 0 (striped data) for a performance boost. Here, the data is stored across both disks – allowing for quicker read/write speeds. However this is particularly bad for WD Green drives, as covered above. You could potentially use RAID 1 (mirrored data) with WD Green drives, though, because the data is ‘backed up’ across all your drives. But in general, avoiding Green drives in a NAS is still the best option.

You can verify this by using Synology’s compatibility tool, which does not list WD Green as a suitable drive choice for your NAS. If I check my own NAS on that list (the DS220+), it lists the following Western Digital drives as compatible:

  • WD Ultrastar DC
  • WD Red Pro
  • WD Red Plus
  • WD Purple
  • WD Gold
  • WD Deskstar

In other words, WD Green drives are not compatible with my NAS. I would be using them entirely at my own risk. Even budget WD Blue drives (that I use for one of my less crucial NASes) aren’t strictly compatible with Synology’s NASes, although that’s a topic for another day.

Here’s what you should do if you do currently have WD Green drives installed in your Synology box.

What To Do If You DO Have WD Green Drives In Your NAS

If you’re reading this article worried, fear not. Simply having WD Green drives in your NAS doesn’t mean that you’ll immediately lose all your data.

Firstly, WD Green drives can be fairly good as secondary or tiered storage. In other words, you could have a 4-bay drive which contains 2-3 expensive SSDs in a RAID array, and then use a large WD Green drive for extra storage capacity:

Diagram showing how to use SSDs and a WD Green in a 4 bay Synology NAS

This can give the best of both worlds: you have a fast and/or redundant RAID array containing your SSDs – where you can keep some of your most crucial files and programs – but you then have a much larger drive for extra storage, such as large 4K videos that you don’t need to access often.

Secondly, always keep backups. If you do use WD Green drives in your Synology NAS – even outside of a RAID array – it is worth keeping proper backups to ensure that you don’t lose any data. Of course, it’s worth keeping backups anyway, but it’s especially important when using incompatible drives in your NAS.

Synology offers various backup solutions including their Hyper Backup software and C2 Storage which allows you to easily backup your entire NAS as often as you configure.

In addition to setting up backups, you should also regularly check the backups – and make sure that everything is being backed up as you would expect. You would never want to try restoring from a backup, only to find that half your files are missing from the backup location.

Where Green Drives Can Be Good

CPU memory and GPU usage when rendering a video

So far I have mainly warned about the perils of Western Digital’s Green drives, but are there any circumstances where they can be useful?

Well yes – as I touched on a bit earlier, they can be fairly good as secondary storage drives. WD Green drives typically offer quite large storage capacities (up to 6 TB), so they can be perfect for storing files on that you don’t access as often.

I sometimes have old 4K video files lying around (for video editing projects that I’m not actively working on), and these are perfect for storing on a slightly slower drive like WD Green.

Plus if your main aim is to save energy, Green drives naturally fit the bill well – offering up to 40% electric reductions compared to some other drives. Just be sure not to use them as part of RAID arrays, or for times when you need to access the data really quickly.

Related Reading: Synology RAM: Why So Expensive? Is Third-Party RAM Fine To Use Instead?