As AI, machine learning, and cloud computing accelerate digital transformation, data centers are consuming more power than ever—pushing utilities to their limits. With grid infrastructure struggling to keep pace, colocation providers like CoreSite are turning to onsite solutions such as fuel cells to generate reliable and clean power to meet the growing demand.
With the help of Jeff Barber, Vice President, Global Data Centers at Bloom Energy, this blog explores the problem of power demand, the growing popularity of onsite power generation, and the advantages of fuel cells as a solution.
Utility providers are reporting significantly longer timelines to deliver power in key U.S. markets, up to two years longer than what colocation providers expect, according to the mid-year update to the 2025 Data Center Power Report, from Bloom Energy.1
“There is a very real technical constraint in power transmission and generation in the U.S.,” explains Barber. “Demand is outpacing what the utility can provide today.”
AI is one of the main drivers behind this trend, and Bloom reports that the median data center size is expected to grow by nearly 115% over the next 10 years, from approximately 175 MW today to about 375 MW.1
Onsite power generation – literally producing electricity at the data center facility – has emerged as a solution to the imbalance between data center power demand in the age of AI and the ability of utilities to supply that power.
“To meet the soaring demand, data centers are adopting onsite power systems as a primary energy source, a shift that reflects the industry’s drive for innovative solutions to address economic imperatives and ease pressure on the nation’s aging power grid,” states Bloom Energy’s 2025 Data Center Power Report.2
Bloom’s 2025 Data Center Power Report: Mid-Year Pulse adds that in 2030, 38% of data centers are expected to use some onsite generation for primary power – up from 13% a year ago – and 27% of facilities expect to be fully powered by onsite generation by 2030, a 27x increase from only 1% just last year.1
Onsite power represents an attractive alternative (and complement) to utility supplied power, especially for colocation data center providers and their customers. “With distributed generation, we can get a colocation provider and their tenants to market years ahead, rather than waiting for interconnections, substations, long lead equipment delivery, and permitting for new transmission lines,” says Barber. “Data centers can circumvent all of that by generating power onsite.”
Bloom Energy’s solid oxide fuel cell (SOFC) offers an effective onsite power solution for data centers, and CoreSite has already deployed this technology in our Milpitas, California and Boston, Massachusetts data center campuses. SOFCs convert fuels, such as natural gas or hydrogen, directly into electricity without combustion, resulting in low to no CO2 emission.
The fuel cell is not new technology – it is a proven source of power that has been around for more than 100 years and was even utilized on NASA’s missions to the moon.
Today, the preferred fuel for fuel cells is natural gas, offering the following advantages for data centers:
Fast Time-to-Power: One of the most compelling advantages of fuel cells is the ability to bypass the long wait times for utilities to scale power. Fuel cells are easy to manufacture, and the modular design enables rapid deployment. Any volume of modules can be clustered together to deliver scalable power, from 100s of kilowatts to 100s of megawatts, and even gigawatts.
“Fuel cells can provide power three-to-seven years sooner than a traditional utility, and four-to eight times faster than other onsite power solutions,” Barber says. “In some cases, we can provide fuel cells in less than six months. It’s a time-to-power advantage delivering very real ROI for a colocation provider and their tenants.”
Robust Reliability: Barber says Bloom Energy fuel cells offer “four nines” availability due to multiple factors. First, the modular fault-tolerant system consists of independent 65-kilowatt modules, so there is no maintenance downtime, and no risk of a cascading failure. Second, the gas network in America is hardened and very resilient, transported via below-ground pipelines with tremendously high availability. The system operates at very a very high efficiency level, typically between 60-50%, with low pressure gas delivery. Compared to combustion the fuel usage is ~30% better.
Low Maintenance: “Bloom fuel cells have zero operational impact to the data center operator, unlike combustion technology with rotating parts that wear out from friction,” Barber asserts. “Once the fuel cell process begins, it just runs.”
Minimal Footprint: Bloom fuel cells deliver high power density and increasing amounts of power as the technology and installation advances, Bloom is now able to deploy in a stacked configuration, doubling the density in the same footprint. With the addition of a simple equipment platform, the units can be installed four-high, providing ~100 MW in an acre.
Gas turbines and reciprocating engines provide up to 50 megawatts of power per acre, while fuel cells can deliver double that – up to 100 megawatts in an acre. This small footprint can help ease communities’ concerns about data centers’ visual impacts and the loss of open space. Another growing concern for communities is the noise levels associated with combustion technologies. Bloom fuel cells operate at 65 dB measured at 10 feet, according to Bloom Energy.3
Clean Power: By converting natural gas into clean electricity, SOFCs achieve ~60% electrical efficiency while virtually eliminating NOx, SOx, and other harmful pollutants. “Fuel cells are a virtually pollution-free, non-intrusive and community-friendly way to provide onsite power,” Barber confirms.
Ideal Design for AI: Finally, maybe one of the most opportune advantages of fuel cells is how well they support AI. “Fuel cells are perfect for the oscillating machine learning and AI workloads,” Barber explains. “Bloom deploys ultra capacitors which are ideal for handling the alternating spikes and troughs of AI workloads. There is an almost instantaneous discharge-recharge buffer between the load profile and the fuel cell, so the platform is able to respond instantly to those oscillating workloads that the industry is struggling with right now.”
What percentage of a data center's power can be generated by fuel cells? Barber says fuel cells are intended to serve as primary base load power, not as backup devices. Fuel cells can be used either to supply 100% of a data center's power or to supplement a grid connection.
So, does this mean someday all data centers may utilize onsite power, especially by fuel cells? The potential is there, and Barber’s vision is a future powered by fuel cells.
“The more forward-looking data centers and utilities are looking to onsite generation,” Barber concludes. “I think that’s a wave that you’re going to see more of.”
About Jeffrey Barber
Jeffrey Barber is the Vice President of Global Data Centers at Bloom Energy, where he drives transformative change in the industry. A global leader with more than 20 years of experience in the digital infrastructure markets, Jeff held key roles at EMC/Dell, Oracle and Prime Data Centers prior to joining Bloom.
At Bloom Energy, Jeff oversees the data center vertical supporting businesses in meeting their mission-critical power needs. In his role, he is dedicated to empowering data center developers, tenants and operators to take control of all their data center power requirements and is passionate about paving a more sustainable path forward for data centers. His dedication to reliable, sustainable and efficient power remains at the forefront of his work, enabling the industry to take control of its most critical asset: access to power
Know More
Visit CoreSite’s Knowledge Base to learn more about the ways in which data centers are meeting clients’ constantly increasing power and other infrastructure requirements.
The Knowledge Base includes informative videos, infographics, articles and more. This digital content hub highlights the pivotal role data centers play in transmitting, processing and storing vast amounts of data across both wireless and wireline networks – acting as the invisible engine that helps keep the modern world running smoothly.
References
1. 2025 Data Center Power Report: Mid-Year Pulse, Bloom Energy, 2025 (source)
2. 2025 Data Center Power Report, Bloom Energy, 2025 (source)
3. How to power the AI economy with fuel cells while supporting local communities, Bloom Energy, June 30, 2025 (source)