What is the Future of Renewable Energy in Powering Data Centers?

The pressure on data centers to deliver reliable performance while also being cost-effective and environmentally friendly is growing at a seemingly exponential rate.

It puts the mission critical facilities industry into the middle of a major transition where demands for increased data storage continue to soar while customers also call for more sustainable systems and corporate accountability. And the increased scrutiny is justified.

How much energy do data centers use?

According to the U.S. Department of Energy and its Office of Energy Efficiency and Renewable Energy (EERE), data centers consume 10 to 50 times the energy per floor space compared to typical office buildings making them one of the most energy-intensive building types being constructed today. Collectively, the EERE says these facilities account for approximately 2 percent of the electricity used nationwide.

Globally, power consumption by data centers is one to 1.5 percent of all electricity used according to a 2022 report from the International Energy Agency (IEA). The IEA also reports that since 2010, “the number of internet users worldwide has more than doubled, while global internet traffic has expanded 20-fold.

It is logical to conclude the corresponding demand for digital services and data center facilities will only grow. How we choose to power these centers will have a major impact on the environment, either positive or negative.

Walking to the Edge of data center power consumption.

While the advent of hyperscale data centers has had success checking the rate of growth in energy consumption due to their economies of scale and the huge contributions of information and communication technology (ICT) experts in paving the way with research and development to optimize information technology (IT) equipment, the consensus seems to be that the future is shifting toward Edge data centers. These facilities are located close to end users and their devices—at the edge of the network, so to speak. Hardware and/or software components are used to temporarily store data thus improving computer response time.

This pivot to these smaller data centers will have a significant impact on energy consumption patterns as water use efficiency (WUE) emerges as the top performance and optimization criterion for site owners. Most of the energy used by data centers goes to maintaining their servers which consume about 1,000 kWh to 160,000 kWh per square meter per year. By comparison, the average American home uses about one-tenth that amount of electricity. The use of more water-efficient cooling systems such as chillers indicates a shift toward a more energy-dense system that seems to work in favor of the more space-constrained Edge data centers.

These smaller data centers have a markedly different design goal from their hyperscale brethren. The current approach to integrate redundancy at a transmission and distribution level will change into interweaving redundancy in deployment sites as small-scale data centers become more prevalent. This creates significant speculation about how global energy production will keep pace with demand as these Edge data centers are easy to quickly deploy. The danger is they may far outpace the capacity for energy growth while also being more energy dense and less efficient than their hyperscale cousins.

Making the case for renewable energy in data centers.

The hunt for quickly deployable modular distributed power generation systems becomes a lot more necessary in the scenario described above. Renewables have been a top choice of distributed generation since their advent. According to the IEA, in 2019 combined renewable energy sources accounted for 23.2 percent of the total global electrical energy supply and have become an integral part of the data center industry.

The use of renewable energy sources such as solar, wind, and geothermal reduces greenhouse gas emissions and helps to reduce dependence on traditional fuels like oil, natural gas, and coal. In addition to reducing carbon emissions, renewable power generation increases sustainability by reducing energy costs while also supporting local economies through employment opportunities that are created when companies install solar panels or wind turbines at their facilities.

Recent moves to renewable sources are largely attributed to hyperscale data center owners. This push toward sustainability has led to investments in renewable energy infrastructure through a mixture of three primary categories:

1. Purchasing Renewable Facility: Build new or buy existing offsite renewable generation to offset energy footprint.
2. Increase Renewable Component: Work with local utility provider for a bigger percentage of renewable mix in the energy provided.
3. Built up Renewable Facility: Build on facility distributed generation and create microgrids.

Based on geography the three approaches vary in popularity. In the U.S., the first two options are more popular since it is relatively easier and more sustainable for the hyperscale builders to work with utilities to add high-capacity lines where it is much easier to control the source contribution or to buy out large renewable farms that offset their energy footprints without having to account for the design and personnel impact on their existing fleet of data centers.

The second approach largely depends on the reliability of the existing grid systems whereas a large part of the redundancy in the design can be pushed to the utility while still accounting for a larger component of renewables in the delivered energy.

Renewables by nature are intermittent sources of electricity. Without a large battery storage component, this intermittency easily gets transmitted to the load end of the distribution. This, coupled with weather-related impacts and other grid design factors, these challenges can cause large-scale grid failure similar to the energy failure event in Texas in February 2021. Finding a balance between an increased renewable component and demand for a more reliable utility makes this an option with volatile stability.

The third approach while not as popular in the U.S., is quite prevalent in some of the developing regions where grid stability cannot be taken as an available approach. It is also worth noting that most of these areas also include the largest anticipated demand for these data centers. When connected with the more scalable Edge data centers, the different approaches to energy production and distribution begin to have an outsized effect on the country-specific approach to renewable energy generation and can act as positive feedback to achieve synergy between the increasing demand for data centers and maximizing the renewable component of energy used in them.

Data center outlook is bright… with a chance of rain.

While there has been good progress in the integration of renewable energy into data centers over the past twenty years, the new reality says it might not be enough to keep up with the expected surge in power demand. The proliferation of Edge computing is creating new challenges that will have to be addressed. With that said, any progress is good.

Incorporating more sustainable energy sources into data center designs is an obvious strategy for facility owners and operators to continue pursuing. Renewable energy is not only good for the environment it can also save money—a win-win situation in any calculation.

Som Ghosh shares his passion and knowledge of sustainable electrical engineering in support of ESD’s mission to improve society through the built environment.

For more information on how our engineers can help with your project, reach out to ESD’s Mission Critical Facilities Engineering team.