Replacing diesel for good: how Pure DC made the switch to hydrotreated vegetable oil work at scale

As part of our commitment to minimise the environmental impact of our data centre infrastructure, Pure DC mandated the use of HVO (hydrogenated/ hydrotreated vegetable oil[1]) from day one at our first UK hyperscale data centre. Our journey began in 2021, driven by Pure DC’s Net Zero ambition. With growing scrutiny on data centre operators to meet Scope 1 Net Zero targets by 2030, HVO has since emerged as a proven and practical solution for reducing carbon emissions.

Our adoption of HVO began with a comprehensive evaluation in 2021. We focused on its technical feasibility, fuel properties, supply chain resilience, and sustainability credentials. This process laid the foundation for its successful deployment at our Brent, London site, where it is used for backup generation. Since then, we’ve expanded its application to short-term primary generation in Dublin and are actively exploring its use in other regions.

Our experience has shown that HVO integrates seamlessly into existing operations. It has so far been fully compatible with our generators, requires no changes to maintenance procedures, and demands no additional training for on-site teams. The transition was straightforward, and once implemented, HVO proved to be a like-for-like replacement for diesel in day-to-day operations.

Technical & environmental benefits

HVO offers a major advantage in storage stability, with a shelf life of up to 10 years[2]. This is due to the absence of FAME (Fatty Acid Methyl Ester), which also contributes to its cleaner burn. Emissions of NOx, PM, and CO are reduced by 10%, 30%, and 25% respectively, supporting air quality reporting.

However, while suppliers are often quick to promote the environmental benefits of HVO, it’s essential to remain vigilant – ISCC certificates should be proactively requested and reviewed on a regular basis.[3]

Actual carbon savings

The most commonly cited figures refer to a lifecycle carbon saving of 90% compared to diesel. A more conservative value can be found in BP’s[4] well-to-wheel analysis, which references a saving of 85% (in transportation).

As a data centre operator, Pure DC includes the emissions from the use of HVO in its Scope 1 and Scope 3 emissions. Since operations began, Pure DC avoided 4,100 t CO2e of direct emissions (scope 1). As direct CO2 emissions are zero rated for biogenic fuels[5] the relative saving of CO2equivalent (which also covers N2O and CH4) have been 97% in comparison to the use of fossil diesel. Across Scope 1 and Scope 3 emissions, the CO2e savings for Pure DC have amounted to an average of 84%.

Cost

Although HVO has a higher per-litre cost, the overall budget impact has been found to be marginal. For example, the initial fuel procurement costs are most relevant for back-up generators yet still represent a tiny fraction of a hyperscale data centre’s construction budget, and operational costs show a premium of less than 20% compared to diesel. In some regions, government incentives help offset these costs.

The use of HVO has helped Pure DC reduce the spend on market instruments (i.e. ETS allowances) for carbon emissions and we had positive feedback from environmental agencies  during permitting applications.

Supply Security

In Europe, where supply chains are well-established, Pure DC has validated HVO availability for its operations through supplier reviews and real-world operations, including the requirement for emergency fuel supply at short notice.

After initial implementation and proof of concept within Pure DC’s London data centre, supply security was further validated for Pure DC’s data centre in Ireland where HVO has been in use for short-term primary power generation.

Our Dublin data centre required close to 3 million litres over the span of 12 months for short-term primary and back-up power generation. This has been met reliably and well within service level agreements from suppliers.

In the unlikely event of a complete HVO supply disruption, operational continuity is further ensured by the option of emergency reversion to diesel which can be used as a drop-in replacement.

Outside Europe, supply availability and feedstock types vary. We continue to monitor these markets closely, recognising that growing demand from data centres can help stimulate supply chain development.

What next?

Pure DC has tested HVO use for both back up and short-term primary electricity generation and fully supports the use of HVO as a renewable fuel alternative to diesel. In addition to using HVO across our own operations, we also encourage and, where possible, require our general contractors to adopt HVO as their default fuel choice during construction.

Having trialled and implemented HVO across a range of use cases over the past four years, we now consider the technology proven and supply chains in many regions sufficiently mature. The consideration of HVO should now be standard practice for all new and existing data centre sites – there is no longer a credible rationale for continued reliance on diesel.

 

References

[1] Hydrotreated vegetable oil – Wikipedia

[2] HVO Fuel Suppliers – SDM Fuel Solutions ; HVO Fuel Transition by AVK | Sustainable Alternative to Diesel
About HVO Fuel – Sustainable Fuel Reducing Net CO2 GHG Emissions | Crown Oil Sustainability ; HVO Fuel Ireland – Irish Leading BIO Fuel Supplier – Klass Oil

[3] Pure actively avoids HVO derived from virgin palm oil, as its use undermines the environmental integrity of the fuel.

[4] bp bioenergy HVO | Products and services | Home

[5] GHG Protocol Corporate Accounting and Reporting Standard