The promise of ‘always on, always available data’ compels technology companies and data center providers to build with double redundancy backup power, often in the form of natural gas or diesel-fueled generators. During maintenance activities, testing, and emergency usage, these diesel generators emit pollutants such as oxides of nitrogen (NOx) and diesel particulate matter (DPM) which are not only harmful to human health, but also contribute to the facility's overall carbon footprint. While one diesel generator at one facility may emit a small quantity of emissions, the sum of these generators across all of a particular company's assets are sizable, and even more so across the entire data center industry. In an effort to achieve zero–carbon and renewable energy goals, key players in the industry have recently begun looking into alternatives, such as battery–based systems, which could reduce or eliminate the need for diesel generators at their data centers.
An air dispersion modeling analysis for a data center was completed to evaluate air quality emissions and data center design impacts of implementing, as backup power options, solely diesel–powered generators versus solely battery–based systems. Modeling simulations of a typical data center layout was performed in three different states with differing climate, terrain, and state air permitting requirements. Modeling results showed that using battery–based systems over diesel–powered generators would allow for more dense, scalable, and flexible data center designs with a wider range of site selection options, all with a smaller carbon footprint, due to a lesser dependence on building locations, source locations, and nearby competing sources in proximity to the facility fenceline and surrounding terrain. This was also due to the reduced environmental impacts on the surrounding community and the reduction in the emissions of each regulated pollutant, putting the data center under specified air quality pollutant standard limits and thereby simplifying the air quality permitting process. Use of battery–based systems in lieu of diesel–powered generators in data center design, if proven feasible in the early experimental stages, are a likely contender to be part of the fundamental design of sustainable urban systems.
