Any data centre facility worth its salt should have a roadmap and sustainability strategy in place. And as sustainability becomes a front-and-centre issue to any data centre conversation, there are several non-negotiable components in the green grid.
Core to any sustainability strategy is a clear understanding from the board and executive team of what should be done to achieve a science-based target of Net Zero by 2050. The said strategy should contain measurable goals, rather than broad sweeping statements. Typically, this should include how the organisation will reduce greenhouse gas emissions (GHG), reduce water usage and increase energy efficiency and the use of renewable energy.
As it currently stands, many data centre operators now have a sustainability team embedded within their workforce – this is naturally a positive development. However, these teams need to work cohesively with other elements of the workforce like operations. Their work cannot endanger reliability, resilience or performance – and this is not their primary area of expertise.
Of course, one of the areas that needs to be considered in an energy intensive data centre is the use of renewable power. This falls into the Scope 1 and Scope 2 GHG emissions and can be quite easy to quantify. In practice this presents several challenges.
PPAs
There has been widespread discussion about the legitimacy of organisations buying up power purchase agreements (PPAs). However, the industry’s cynics, which I will freely admit to being, could say, ‘is this power actually available?’ and ‘is this power being injected into the grid that the DC’s are fed from?’. Often the answer is no, the power is not being injected into the grid.
There is no way to denmark green electrons from any other electrons. Power is power and what is obtained from the grid is blended from a cocktail of sources. The difficulty arises when the grid generation is made up of carbon heavy sources like coal and to a greater extent, gas. If the grid is 75% carbon heavy, any importation of lower carbon energy from a nearby country will only dilute a proportion of the grid by a few percentage points.
Solar
Solar is a sound renewable power source with caveats. Any solar programme needs to be tied into an efficient battery energy storage system (BESS), to be of use. Solar does not generate at night and that which is generated in the day may need to be stored to charge electric vehicles overnight, for example. It is possible to use such power for ‘parasitic loads’ such as lighting and other non-critical uses. Even if this power is being offered back to the grid, a consistent question we hear is can the grid have taken additional capacity?
Another way to use renewable power is to disconnect the data centre from the grid. Some have taken the option of becoming a stand-alone facility with a cogeneration plant onsite or using gas fired fuel cells. The latter does require a connection to the gas grid, which is much more reliable than the power grid. There are examples in EMEA and USA of both approaches making use of the byproducts of the generation process with success.
Wind
There is such a thing as the wrong type of wind – look at Malaysia. In other words, the average wind speed is 2m/second and the minimum wind speed for wind turbines is 4m/second even though most coastal and offshore locations do not achieve a viable wind speed. The only exceptions to this might be Kuala Terengganu, Mersing and Kudat areas of the country, according to some studies.
Can we make the facility more efficient?
Over the last few years, there have been undeniable improvements in facility data centre efficiency. The only way the facility will become more efficient is with the use of adaptive power provisioning that right sizes to the power draw.
As a capital plant reaches the end of its service life, we recommend replacing the facility with more energy efficient models that are sized to meet actual demand rather than the over estimations of what might be needed in the future. Ensure that you are provisioning a biodiesel for emergency power generation – do you actually need generators? Can you live with 99.99% availability, or must you have 99.999% availability?
Does PUE need to be retired?
It has been said that you can’t manage what you can’t measure. This statement leads to another pressing question – what measures are there in place to measure data centre efficiency?
Recently, there has been more than one article stating that power usage effectiveness (PUE) has run its course as an efficiency metric. Let’s be clear about one thing, PUE was NEVER, is not and never will be an efficiency metric! PUE simply demonstrates the amount of load that the facility uses in addition to the IT power load, which being the ‘1’ in the PUE metric. The smaller the ratio the less power the facility needs, however, it is a metric that is affected by a raft of factors such as load, environmental conditions to name but two.
To start with, it needs to be understood in the context of baseline reporting. It needs to be a 12-month trailing figure measured against a common international standard. ISO/IEC30134 series or EN50600-4-X series. Once you start to measure according to these standards and be prepared to be audited against them you will be on the way to baselining your facility and then can see how to improve.
There is nothing wrong with PUE……. it’s the people and organisations who do not either use it correctly or understand what it actually is, that presents the issue.
It is one of a range of metrics that will help to give a holistic picture of your facility – not a means to compare it to another facility!
What is possible?
Can we green the grid or get our data centre facilities to be greener? Yes, we can, but it does require owners/operators to be creative in how they power their facilities and the uptime that they might offer. It does not mean that virtual PPAs are the way to go. There is an argument that PPAs exist purely within the realms of self-serving greenwashing. The use of hydrogen produced by green sources is not currently available at scale and the distribution methods will not be available for at least 10 years. Nuclear is always an option and several countries in Southeast Asia are considering this, but the regulatory processes and other concerns may mean that this is much more of a medium-term option.