We are witnessing a data center boom. A combination of economic, societal, and technological factors such as the growth of electric vehicle adoption, cloud computing, AI and machine learning, and the proliferation of connected and smart devices are all driving the demand.
When it comes to leading this boom, the United States is ahead of the rest of the world by a significant margin. By 2023, the US already had more than 5,000 data centers, more than 10 times that of Germany, which was in the second spot.
According to a research study by the CBRE Group, the amount of data center supply under construction in North America's top markets in 2024 jumped by nearly 70 percent compared to the year prior.
In fact, the study showed that in the first half of 2024, more than 500 megawatts of new data centers debuted in the biggest markets in the US and Canada. Further, new data center inventory grew by 10 percent in the first six months of the year, while jumping 23 percent from the year before.
Looking ahead, the trend is set to continue on an upward path. According to Research and Markets, the data center construction market was valued at USD 61.84 billion in 2023 and is expected to reach USD 113.62 billion by 2029, rising at a CAGR of 10.67 percent.
The power behind the scenes
With this growing reliance on data centers, so is the need for stable and uninterrupted supplies of electricity and backup power for the centers to sustain reliable, successful operation even during main power grid outages.
When a data center or other mission-critical operation suffers a power outage, even if only briefly, the result can be high-impact, expensive, and even life-threatening disruptions.
Although not often visible or thought about day-to-day, backup power systems are vital to the data center boom, offering crucial support by supplying uninterrupted power, maintaining connectivity, protecting data integrity, and keeping vital functions such as cooling systems up and running.
Balancing act
However, these driving demands we see for power need to be balanced with environmental impact, especially in terms of greenhouse gas emissions. Many data center companies such as Amazon Web Services, Google Cloud, and Microsoft Azure Services have ESG targets to limit their overall impact on the environment, such as specific goals to operate carbon-free and to use 100 percent renewable energy sources within a certain timeframe.
When it comes to the critical backup power that data centers rely on, efforts to lessen environmental impact by power generation companies are also underway.
As of today, diesel-powered generator sets are the top choice for backup power for data center applications thanks to their proven reliability with the best power density of any power generation source. In addition, diesel systems are not only affordable compared to other options, but they also provide quick response times, high load-carrying capacity, and are supported by a large contingent of maintenance and service suppliers.
The obvious downside to diesel systems is the practice of running on fossil fuel and the resulting emissions, even though these backup systems usually only run for a short period each month for testing purposes.
But there is good news for the future of diesel-powered backup systems.
A trio of options for improvement
1. For one, modern diesel engines can run on sustainable fuels such as HVO from providers such as Neste – currently the world’s leading producer of renewable diesel – that significantly reduce emissions and can be used as a drop-in fuel without any changes needed to the engine that powers data center backup generators. Because HVO is produced from renewable raw materials, its production, transport, and combustion generate next to no greenhouse gas emissions.
Testing has shown no power loss when using HVO as a fuel replacement in terms of maximum power, load acceptance, and fuel consumption compared to conventional fossil diesel. Greenhouse gas emissions can be reduced by as much as 75 percent to 95 percent when emissions over the fuel’s life cycle are compared with fossil diesel.
2. Secondly, Some diesel genset manufacturers such as Rolls-Royce offer options to extend test run intervals for data center customers from monthly to quarterly, guaranteeing the same reliability and performance.
Most often, any location that operates standby generators for emergency backup power undergoes test runs once per month to ensure they’re ready to perform effectively during an actual power outage. During these tests, the generator is started and observed to ensure its smooth operation, helping to guarantee that in the event of a power outage, the emergency generators can swiftly and reliably take over the power supply. These monthly tests mean that data center customers are using fuel 12 times per year, generating emissions, all just to ensure the integrity of the emergency backup power.
But by reducing the number of monthly starts from twelve per year to four, emissions related to the process can be cut by two-thirds. This is a significant benefit for data centers and other critical infrastructure segments, which often have strict limits on the amount of emissions they are allowed to produce.
Reducing these test runs is possible by using an interval pre-lubrication pump in the generator system, which lubricates the generator engine and periodically circulates oil through the engine to maintain a layer on critical components. This ensures that the unit is prepared to start within seconds when needed. The pump is integrated into the engine, preserving the generator's footprint, and can be retrofitted into existing units.
3. Third, the addition of custom after-treatment systems – which are specialized components or modifications designed to reduce emissions by managing and treating exhaust gasses produced by diesel engines. Systems such as those available for Rolls-Royce’s mtu diesel gensets can also help to meet specific regulatory or operational requirements.
One example is a selective catalytic reduction (SCR) system that can convert harmful nitrous oxides from engine exhaust gas into water and nitrogen. In many cases, such SCR systems can remove most of the NOx produced during the combustion process from the exhaust gas.
Another option is the use of diesel particulate filters or DPFs, which capture and store particulate matter from an engine’s exhaust to ensure optimal filtration.
When utilized, these three steps offer ways to reduce diesel genset emissions by up to 90 percent, giving data center operators the ability to meet accelerating demands for connectivity and power while reducing environmental impact using proven technology that is available today.