BESS & Carbon: Arcadis' Sustainable Data Centre Design

Sequestered carbon dioxide at a California data centre could help to increase the produce yield of plants like strawberries and tomatoes. 

Designed by Arcadis, the Terra Ventures data centre will cover 27,000 square metres and use a self-sufficient microgrid to reduce environmental impact.

Jeffrey Gyzen is Principal and Global Practice Group Director for Mission Critical & Industrial Facilities at Arcadis.

Across his career he has been involved in the design of more than 250 mission-critical facilities worldwide and played a key role in establishing the ANSI/CSA/EIA/TIA-942 standard.

Jeffrey shares the details behind the Terra Ventures data centre project.

What sustainability challenges do data centres face?

Data centres are among the world’s most energy-intensive building types, consuming up to 50 times more energy per square foot than a typical office building. They account for approximately 2% of total electricity use in the US and up to 5% of global greenhouse gas emissions.

One of the most significant sustainability challenges is the energy required to power the servers and the cooling systems that keep them running efficiently. Traditional cooling methods using air, such as computer room air conditioning (CRAC) units, are inefficient. In contrast, innovations like direct-to-chip liquid cooling can significantly reduce energy requirements in data centres with higher densities.

Another critical area is environmental operating parameters. Data centres have historically maintained strict control over temperature and humidity levels, resulting in excess energy use.

Expanding these ranges can decrease cooling demands without significantly compromising performance, especially considering the server refresh rates typically employed by most operators. Reliance on diesel generators for backup power, though reliable, generates significant emissions.

The growing popularity of on-site power generation can eliminate both diesel generators and UPS systems when the power reliability requirements, typically five-9s or 99.999%, are built into the design of the on-site power generating systems.

When on-site power generation is not an option, battery energy storage systems (BESS) can potentially offer a cleaner alternative to diesel generators for short outages.

What is community-centred design and how can it benefit data centres?

Community-centred design is an approach that considers how a facility can serve not just its operational goals but also the surrounding community’s social, environmental and economic needs.

We’re rethinking what data centres offer. Rather than power-hungry, big, ugly grey boxes, we can transform these facilities into hubs for sustainability and community wellbeing by giving back rather than taking from the neighbourhood.

In a later phase of the Terra Ventures data centre project, we’ll be integrating a greenhouse to supply fresh produce to the local community.

This technique will repurpose some of the carbon dioxide and water vapor produced as by-products from the campus’s on-site fuel cell power generation system to support plant growth.

We also plan to feature community rooms and educational classes, encouraging local engagement and reinforcing the connection between technology and sustainable development.

How will the Terra Ventures data centre combat energy challenges?

We designed the Terra Ventures data centre to be one of the world’s most sustainable data centres, tracking near-net zero carbon emissions. Some estimates suggest that 95% to 98% of a data centre’s total carbon emissions come from operational energy use, so this is where we directed our attention.

By utilising absorption chillers to produce chilled water from the waste heat generated by the fuel cells, we will minimise the massive amounts of energy required for cooling these facilities. We expect this approach to reduce cooling energy use by up to 70% compared to conventional cooling systems.

Another highlight is the switch from alternating current (AC) to direct current (DC) power for all IT server loads, which will improve energy efficiency by minimising the conversion losses inherent in AC-DC conversions.

This innovation is still relatively uncommon in the data centre industry and represents a forward-looking move to optimise power delivery, especially considering that fuel cells produce 400V DC power.

Finally, every bit of carbon makes a difference. Throughout the design, we emphasise reducing embodied carbon through intelligent material selections and effective structural design, in line with our broader objectives of lifecycle sustainability.

What technological advancements make this data centre different?

The on-site power generation utilising fuel cells represents a significant departure from the traditional utility grid connection that most data centres currently rely on. These fuel cells produce continuous power with less than half the carbon dioxide output when compared to a typical utility.

These reduced amounts of carbon dioxide can be partially sequestered along with the fuel cell’s other by-product, water vapor, to further reduce the data centre’s carbon footprint.

This sequestered carbon dioxide can then be used in the greenhouse to increase the produce yield by as much as 60%. Tomatoes and strawberries are particularly receptive to increased levels of carbon dioxide.

The absorption chiller system is another standout feature. By harnessing waste heat from the fuel cells, we can drive the cooling process with significantly less energy, thereby dramatically improving the overall efficiency of the facility.

Switching to DC power distribution is also a noteworthy advancement. DC power can reduce energy losses by up to 15% compared to traditional AC-powered systems, especially in IT loads where DC power is the end requirement.

This move helps us reduce wasteful conversions and points the way toward a more streamlined and efficient data centre design.

Altogether, these innovations form a holistic approach that tackles sustainability from every angle. It’s a model that we hope others in the industry will look to as a blueprint for sustainable, community-integrated data centres worldwide.