Jacky Pluchon, VP EMEA Power Solutions at Kohler Power EMEA, sat down with DCR to answer some key questions about the genset landscape.

DCR: What are the key considerations to keep in mind when designing generator packages for data centres?

JP: The data centre industry is thriving, which is causing some supply chain constraints to emerge. For example, at the time of writing, lead time for critical data centre equipment like generators is between six and nine months and could be even longer if third party fabricators are involved. Using a dedicated supplier for design, manufacture, testing and inspection of generator equipment can help to overcome supply chain issues and provide a more flexible approach to changes in market demand.

Data centres also operate in vastly different contexts. Regional regulations for emissions or sound vary significantly from one area to another. Also, edge data centres have different needs to hyperscale solutions. Gensets must meet the specific needs of their data centre to provide the emergency backup function they require.

DCR: What’s the importance of periodic testing of back-up generators, and how often should this be done?

JP: There are two competing priorities that must both be met when considering a back-up generator test frequency:

• Regular testing helps to ensure that the generator will start when needed and keep the data centre running reliably despite long periods of dormancy.
• Testing generates carbon emissions and the more frequent the testing, the greater the carbon footprint of the data centre.

Kohler is constantly seeking to improve the test processes so that we can improve the reliability performance of a data centre and also reduce their carbon footprint by optimising the test frequency.

DCR: Sustainability is the watchword for the data centre industry right now. How can genset manufacture become more sustainable?

It’s true that sustainability is a key focus area for the data centre industry. This focus is driven by the introduction of more and more stringent regulations, as well as end-user awareness and concern over an organisation’s carbon footprint.

GAFAM organisations are especially vigilant with regard to public perception of their environmental impact. They are constantly looking for ways to reduce their carbon footprint, which includes an increased pressure on suppliers of mission-critical power systems to improve the environmental performance of their gensets.

However, approaches to sustainability should take immediate concerns and a long-term strategic plan into account. Data centres without a clear technological roadmap for the future run the risk of adopting short-term solutions that hamper their long-term environmental performance. Kohler has a defined strategy for short, medium, and long-term improvement in sustainability.

The short-term focus is on implementing technologies that improve the efficiency of generators. These solutions are primarily aimed at exhaust gas after-treatment, including diesel oxidation catalysts, diesel particle filters and selective catalytic reduction. For example, Kohler’s technology ensures that our generators meet local emission standards and offer the lowest emissions currently possible.

Our mid-term strategies focus on adopting ‘pathway’ technologies that further reduce emissions. Using bio-sourced or ‘green’ diesels and hydrotreated vegetable oil (HVOs) can reduce CO2 emissions by up to 80% over the lifetime of a generator engine. There is also the advantage that these bio-based liquid fuels are produced from readily available existing feedstocks like rapeseed, sunflower, and soybean oil.

A long-term view of data centre sustainability should focus on hydrogen fuel cells and utility scale batteries. Advances in lithium-ion technology and renewable energy supplies offer a step change in emission reduction. Kohler is working with hyperscale data centre operators to develop technologies in this space into commercial operation.

DCR: Are you seeing a shift towards modular solutions, and what are the benefits of this approach?

JP: The Covid pandemic has caused a major shift towards online living, which has created a significant demand for increased data centre capacity. The benefit of modular designs is that they allow for a high level of flexibility in responding to sudden and large changes in market demand. Data centre operators are seeing these benefits and moving towards modular solutions as a means to secure their capital investment and take advantage of new opportunities.

Power Optimised Design Solutions (PODS) are low- and medium-voltage generator sets that provide the flexibility for modular data centre solutions. Kohler designs PODS with customised options connected and tested before installation. This includes any soundproofing and skin-tight enclosures needed for edge or regional data centres as well as the walk-in 45-foot density PODS for hyperscale data centres. They are delivered complete and can be rapidly installed on an external concrete slab. PODS have the capability to be racked or stacked to add extra capacity as the data centre needs grow.

Modular systems enable data centres to meet the rapidly changing market demands of the industry quickly and efficiently. They provide the scalability data centres need with a low-cost expansion path as and when required. Edge, regional and hyperscale data centres can all use the modular approach to achieve the flexibility they require while still meeting local regulations and requirements.

DCR: What do you see as the emerging trends for data centre power generation in 2022?

JP: Gartner research shows that end-user data infrastructure spending is expected to increase by 6% from 2020 to 2021, reaching a value of $200 billion. Megatrends like public cloud and 5G adoption will continue to drive the demand for data service upwards in the years to come. Increased traffic from the rise in remote work and the adoption of cloud services will also contribute to market expansion, leading to investment in a variety of types and sizes of data centres.

Small data centres of up to 5MW serve as edge solutions close to where the data is consumed in metropolitan areas. Space and noise constraints are primary concerns and the environmental emission regulations tend to be the most stringent in these areas.

Mid-scale data centres of up to 25MW are used as colocation facilities for several third-party organisations. They should offer scalability for servers, cooling, power, and security so that they can offer maximum flexibility in a fast-changing environment.

Large-scale hyperscale data centres of up to 500MW offer business-critical solutions for global organisations like Google, Apple, Facebook, and Amazon. These organisations demand high levels of automation and optimisation of energy use.

Every data centre faces the increased focus on emissions. Even though back-up gensets do not operate continuously, or even frequently, they still generate emissions and have a role to play in improving the carbon footprint of the data centre as a whole. Technological innovations towards this end will continue to play a significant role in the industry in the future.