Today the five-nines principle, or 99.999% uptime, is something that practically all data centre providers will promise customers. And to achieve this, many operators across the globe will rely on fossil-fuelled backup generators as a means of mitigating power or grid failures. The overwhelming majority of these gen-sets are powered by traditional, mineral diesel, which in the current climate of Net Zero and carbon neutral emissions targets, is a smudge on any data centre’s copy book.
Even the greenest of green data centres up in the Arctic Circle still rely on diesel fired backup generators - so this is an area applicable to every data centre globally.
One argument is that if data centres operate at five-nines uptime rates, do we need to really worry? There could, in fact, be thousands of generators lying dormant, un-used and idle because data centres have been successfully designed and engineered to be as resilient as possible. That is of course entirely plausible. Indeed, data centres are designed not to need their generators, which is why they’re the last resort of backup power.
However, they still need to be tested regularly and when you start to do the math on that alone, it’s alarming how quickly the emissions will sky-rocket. To maintain resilience and optimum performance, a normal 1-1.75MW diesel-powered generator, for example, needs to be fired-up for 2 hours per month to test it.
So, that’s 24 hours every year running it at full throttle. Now, this doesn’t sound like a lot, but when you consider you need roughly one generator for every megawatt of power provision, and according to the latest figures just in the London/M25 ring we’re utilising around 1,000 megawatts, we’re already looking at 24,000 hours of continuous diesel emissions – just from testing our equipment in the Greater London region.
Now to continue the math, very approximately, a diesel generator running for an hour burns around 450 litres of diesel, and with traditional, mineral diesel estimated to produce 3.1 tons of Greenhouse Gas (GHG) CO2 for every 1000 litres of fuel burned, the emissions quickly add up. Just testing our generators within the Greater London region on an annual basis pumps almost 33,500 tonnes of CO2 into the atmosphere - the equivalent of more than 2,000 UK family homes on an annual basis.
Extrapolate that to the fact data centres could account for anything up to a projected 3% of global electricity use, (with a large percentage of those being Tier 3, 99.999% uptime facilities), our industry’s diesel generator backup testing regime alone could be responsible for the carbon output of fairly sizeable country!
Other, cleaner means than diesel, however, do prevail. Hydrogen gas and electrification, for example, have long-been tested in our sector but right now come with complications such as the need for radical infrastructure changes.
A better alternative
Over the past decade a great deal of research and development has been invested in developing synthetic, renewable fuels such as hydrotreated vegetable oil (HVO). Yet market adoption, at least within the data centre sector, has been slow to come to the fore. Part of this may be due to the lack of awareness surrounding its capabilities and genuine sustainability credentials. According to the Royal Academy of Engineering (RAOE), “Gauging the sustainability of liquid biofuels is a complex undertaking. However, complexity is no excuse for inaction as liquid biofuels will be needed if the UK’s ambitious decarbonisation targets are to be met.”
At Kao Data, we have long been on a quest to become carbon neutral, and we are powered by 100% renewable energy, use refrigerant-free Indirect Evaporative Cooling and operate a hyper-energy efficient PUE of <1.2, even at partial loads. (Download our white paper to learn more about data centre sustainability)
Around 18 months ago, we started discussions with our fuel supplier, Crown Oil, on a direct replacement for diesel within our backup generators. One that was beginning to show positive results in other European markets, such as automotive. After reviewing its technical specification, we knew that we wanted to be involved in the pioneering trials of this latest renewable fuel alternative, primarily to test and evaluate the validity of the emissions, as well as the operational impact on our engineering systems.
For those unaware, HVO is an advanced, synthetic, renewable fuel created through a hydro treatment of recycled vegetable oil, which creates a very pure liquid. One benefit is its higher calorific value, which generates more energy per unit of fuel compared to standard diesel or biodiesels. And while being 100% biodegradable, sustainable and non-toxic, it provides the same level of resilience as ‘traditional’ fossil fuels, ensuring end-users can maintain mission-critical reliability, while preventing the risk of microbial attack.
At Kao Data, we were both surprised and impressed by the findings, which demonstrated that HVO was a true alternative to diesel. So, after rigorous due diligence, we recently became the first UK data centre to transition all our backup generators to HVO, removing an initial 45,000 litres of fossil-fuel diesel from site. This fuel change reduces harmful emissions by up to 90 % of net CO2, and together with our 100% renewable energy agreements, are major steps in reaching our Net Zero commitments.
The price of sustainability
As with any disruptive change, there is, however, a price to pay. The cost of HVO, for example, is currently higher than other fossil fuel alternatives. On balance, however, there is no price that will outweigh any investment towards reducing the impact of climate change. The benefits of using HVO, therefore, far outweigh the drawbacks.
Our decision to remove standard diesel from our campus effectively eliminates fossil fuels from our facility, most importantly, without degradation of the service to our customers. We believe that this is an important step not just for Kao Data, but for all industry stakeholders serious about reducing their carbon footprint. Furthermore, it benefits customers by helping reduce Scope 3 emissions in the supply chain, something of paramount importance to operators across the globe.
With Net Zero less than a decade away, sustainable, renewable fuels such as HVO, have provided us with a key vehicle to address a host of environmental, economic, and social issues, especially considering GHG (greenhouse gas) Protocols, Scope 1- 3 reporting and COP-26, later this year.
It demonstrates how by applying a logical, simple, and easy to transition fuel source, our industry can significantly reduce its carbon impact, without complex infrastructure changes, for the good of the environment. For more information, watch our video here:
Adam Nethersole
Adam Nethersole is VP of Marketing at Kao Data and his experience covers a decade of working within data centres and digital infrastructure. Interested in green tech and sustainable computing.