Underwater data centres might be the wave of the future

The ever-growing mountains of data we generate need homes. Traditional land-based data centres, with their sprawling footprints and insatiable energy demands, are feeling the heat.

This has sparked interest in an interesting possible solution: underwater data centres. With Microsoft's successful Project Natick showcasing its potential, will your next data centre be located underwater?

Data centres have been submerged underwater in both the Pacific Ocean and Atlantic Ocean since 2015. Microsoft deployed its first underwater data centre into the Pacific Ocean, off the coast of California, as part of an experiment called Project Natick. Phase 1 involved a vessel carrying a single rack with 24 servers.

After Microsoft's successful proof-of-concept tests, oceanic data centres have expanded in size. Phase 2 of Project Natick features a shipping container-sized data centre with 12 racks, housing a total of 864 servers.

In addition, prototypes and tests for underwater data centres have been conducted by Beijing Highlander Digital Technology, based in China, and Subsea Cloud, based in Los Angeles, California. There have been discussions about the possibility of Amazon Web Services (AWS), Google, and Facebook (Meta Platforms) exploring underwater data centre research.

But why are data centres taking the plunge?

Siren song of the deep

One of the primary advantages of underwater data centres is the improved cooling efficiency. Traditional data centres generate significant heat, requiring substantial energy for cooling systems.

The ocean acts as a giant, virtually limitless air conditioner, eliminating the need for energy-guzzling cooling systems. This translates to significantly reduced carbon footprint.

Underwater data centres do not require water for cooling or any other operational needs.

Therefore, these facilities do not put pressure on freshwater resources, which are crucial for both humans and the environment. Water sustainability metrics show that underwater data centres achieve a remarkable water usage effectiveness (WUE) of zero. By contrast, land-based data centres consume up to 4.8 litres of water per kilowatt-hour (kWh).

Data centre cooling is a crucial element in ensuring smooth operations, and it can significantly impact the overall expenses of the facility. As a result, underwater data centres have a financial advantage over traditional, land-based data centres due to their ability to minimise cooling costs.

For example, Microsoft claims that its most recent underwater data centre, which was submerged 36 metres below sea level, had temperatures about 10 degrees Celsius lower than land-based data centres.

According to energy efficiency metrics, Microsoft's underwater computing facility has a power usage effectiveness (PUE) of 1.07, while the company's newly constructed land-based data centres have a PUE of around 1.125.

Underwater data centres offer a solution for achieving low-latency connectivity, which effectively reduces the time it takes for data to travel between its source and destination. Oceanic data centres offer a crucial advantage by providing fast and reliable connectivity to people living near the coast. It's worth noting that over half of the global population resides within 200 kilometres of the coast.

Underserved communities can benefit from faster and more seamless internet browsing, video streaming, gaming, and cloud services by situating underwater data centres close to a significant portion of the global population.

Typically, underwater data centres are constructed using pre-fabricated and standardised modules, allowing for fast construction and delivery. As an illustration, Microsoft's underwater computing initiative aims to complete the deployment process within a timeframe of "less than 90 days from the factory to operation."

Underwater data centres provide a remarkable level of dependability and consistent performance. The reason for this is that these modules are pre-fabricated and built to precise specifications in a controlled factory environment. This allows the oceanic data centres to operate independently, without the need for on-site staff, and remain maintenance-free for a period of up to 5 years.

The underwater data centre project by Microsoft showcased a process where the data centre vessel is retrieved, loaded with new servers, and then redeployed after each 5-year deployment cycle. In total, this process can be repeated for a maximum of four deployments throughout a 20-year lifespan. Afterwards, the underwater facility will be decommissioned and recycled.

Don't dive in headfirst!

However, underwater data centres come with their own unique set of challenges. The most difficult aspect of operating underwater data centres is likely to be hardware maintenance. When a server or disc drive needs to be replaced, sending personnel underwater or transporting the data centre to the surface is far more difficult than with land-based data centres. Robotic automation could help mitigate this issue, but until that technology matures, most data centre maintenance will continue to be performed by humans.

Connecting underwater data centres to network cables is the only feasible way to ensure high-performance networking. That is feasible but expensive, particularly for underwater data centres located far from the shore.

In some ways, underwater data centres are extremely secure against physical intruders because it would be extremely difficult for trespassers to enter them undetected. On the flip side they may be vulnerable to attacks by terrorists or nation-state actors, who are more likely to target a facility at sea than one on defensible dry land.

While obtaining energy from renewable offshore sources is appealing, they are not always reliable. Offshore wind farms, for example, stop working on calm days, and ocean currents can shift, leaving generators idle. Engineers would need to develop backup power sources to ensure the reliability of underwater data centres. While Project Natick demonstrated feasibility, scaling it up to handle the massive data processing needs of global tech giants remains a significant challenge.

There are environmental concerns as well. Leaks and potential damage to marine life remain potential risks despite advancements in mitigation strategies. Careful environmental impact assessments and regulations are crucial.

Navigate tricky waters

These challenges are likely the reason why underwater data centres are still a topic of much discussion but have seen limited implementation. Project Natick has garnered significant attention, yet it's been three years since Microsoft retrieved it from the ocean and there have been no subsequent advancements in the project thus far.

Exploring hybrid solutions that combine land-based and underwater facilities could offer a more practical approach. Imagine a data centre archipelago, with some facilities on land and others submerged, each playing a role in the digital ecosystem. Additionally, technological advancements in materials, robotics, and remote monitoring could address the maintenance and repair challenges, making underwater interventions less like deep-sea dives and more like routine checkups.

Ultimately, the future of underwater data centres hinges on overcoming the current (get it?) challenges and balancing the benefits with potential risks. While it might not be an immediate solution, the potential rewards in terms of sustainability and efficiency make it a technology worth keeping an eye on.

So, the next time you're scrolling through your social media feed, remember that the data powering your experience might one day be stored in a server nestled deep beneath the surface.