What generators are used in data centers?

In today’s digital world, data centers are the backbone of global communication, cloud computing, and enterprise operations. 

These facilities store, process, and distribute massive amounts of data 24/7, making power reliability critical. 

Any power outage in a data center can result in significant financial losses, service disruptions, and security risks. 

To prevent such catastrophes, data centers rely on robust backup power solutions—primarily industrial-grade generators designed to provide uninterrupted power during grid failures.

This article look at the types of generators used in data centers, how they are sized, their redundancy configurations, compliance requirements, and future trends in power backup solutions. 

If you are looking for a reliable backup power solution for your data center, understanding these aspects will help you make informed decisions.

Why Data Centers Need Backup Generators

Power outages in data centers can be catastrophic, leading to data loss, system failures, and costly downtime. 

Studies show that even a few minutes of downtime can cost businesses thousands, if not millions, of dollars.

Impact of Power Outages on Data Centers

Power failures in data centers can result from various factors, including extreme weather, grid failures, equipment malfunctions, and cyberattacks. 

When power is lost, critical IT systems, networking devices, and storage servers shut down abruptly, leading to:

• Service disruptions – Cloud applications, banking systems, and e-commerce platforms go offline.

• Data corruption – Unplanned shutdowns can damage databases and files.

• Financial losses – Downtime can cost up to $9,000 per minute, according to industry reports.

• Security threats – Outages can expose vulnerabilities, increasing the risk of cyberattacks.

Regulatory and Compliance Requirements for Data Center Power Backup

Industry standards require data centers to have reliable backup power. Some key regulations include:

• Uptime Institute's Tier Standards – Defines the level of redundancy needed.

• EPA Tier 4 Compliance – Controls emissions from backup generators.

• ISO 27001 & ISO 50001 – Covers energy efficiency and security protocols.

To comply with these regulations, data centers use high-performance generators that ensure uninterrupted power supply, regardless of grid conditions.

Types of Generators Used in Data Centers

Choosing the right generator depends on a data center's size, power requirements, environmental regulations, and redundancy strategy. 

Here are the most commonly used generator types:

Diesel Generators: The Industry Standard

Diesel generators are the most widely used backup power solution in data centers due to their reliability, fuel efficiency, and ability to generate high power output.

Advantages of Diesel Generators in Data Centers

• Fast response time – Diesel generators can start within 10 seconds.

• High power capacity – Suitable for hyperscale and enterprise data centers.

• Durability and longevity – Can operate continuously for extended periods.

• Low maintenance – Compared to natural gas or bi-fuel alternatives.

Challenges of Diesel Generators

• Emission regulations – Must comply with EPA Tier 4 standards.

• Fuel storage and logistics – Requires on-site diesel tanks, which need periodic refueling.

Natural Gas Generators: An Alternative to Diesel

Natural gas generators are increasingly being adopted in data centers due to environmental concerns and lower fuel costs.

Pros of Natural Gas Generators

• Lower emissions – More eco-friendly compared to diesel.

• Cost-effective fuel supply – Natural gas is cheaper in some regions.

• Less on-site storage needed – Fuel is supplied through pipelines.

Cons of Natural Gas Generators

• Longer startup time – Takes 30–60 seconds to reach full load.

• Dependency on gas supply – If gas pipelines are disrupted, power continuity is at risk.

Bi-Fuel Generators: Combining Diesel and Natural Gas

Bi-fuel generators offer the best of both worlds by using a mix of diesel and natural gas. 

They start with diesel and transition to natural gas, reducing emissions while maintaining reliability.

Key Benefits of Bi-Fuel Generators

• Greater fuel flexibility – Reduces dependency on a single fuel type.

• Lower emissions – Meets environmental regulations more easily.

• Improved efficiency – Optimizes fuel consumption for cost savings.

Hydrogen and Fuel Cell Generators: The Future of Data Center Power

Hydrogen fuel cells are an emerging backup power solution for data centers, offering zero emissions and quiet operation.

Advantages of Hydrogen Fuel Cells

• 100% clean energy – Produces only water as a byproduct.

• Minimal maintenance – No moving parts, reducing wear and tear.

• Scalability – Can be deployed in modular configurations.

Challenges of Hydrogen Generators

• High infrastructure costs – Requires special storage and fueling systems.

• Limited availability – Hydrogen fuel infrastructure is still developing.

Generator Sizing and Load Capacity for Data Centers

Selecting the right generator size is critical to ensuring reliable power backup.

Factors That Determine Generator Sizing

• Total power load – Includes IT equipment, cooling systems, and lighting.

• Peak vs. continuous load – Some equipment draws more power at startup.

• Redundancy levels – Whether the data center follows N+1, 2N, or 2N+1 configurations.

Generator Redundancy Strategies

Data centers implement redundancy to ensure continuous operation even if a generator fails.

• N+1 Redundancy – One extra generator beyond required capacity.

• 2N Redundancy – Two independent generator systems for full failover protection.

• 2N+1 Redundancy – Highest level, providing an extra backup for each system.

Diesel Generators vs. UPS Systems: Which One Do Data Centers Need?

While generators provide long-term backup power, Uninterruptible Power Supply (UPS) systems offer short-term energy storage to bridge the gap between power loss and generator startup.

Key Differences Between Diesel Generators and UPS Systems

Feature. Generators. UPS syste

Power      long-term. Shorter(m)

Duration.

Start-up     10-30s           Instand

Time

Energy  Diesel/Natural Batterie

                         Gas

Source

 

Most data centers use both UPS and diesel generators to ensure seamless power continuity.

Compliance and Environmental Regulations for Data Center Generators

Uptime Institute Tier Certification

• Tier 1 – Basic power backup, no redundancy.

• Tier 2 – Redundant components but single distribution path.

• Tier 3 – Concurrently maintainable infrastructure.

• Tier 4 – Fully fault-tolerant with 2N+1 redundancy.

EPA Tier 4 Standards

Regulates emissions from diesel generators, requiring advanced filtration systems and fuel treatment.

Future Trends in Data Center Power Backup

1. Microgrid Technology for Data Centers

Microgrids integrate multiple energy sources (solar, wind, batteries) to create localized, self-sufficient power networks.

2. AI-Driven Generator Maintenance

AI-powered predictive maintenance can detect potential failures before they happen, reducing downtime and maintenance costs.

3. Battery Storage as a Diesel Generator Alternative

Lithium-ion and solid-state batteries are emerging as viable alternatives to traditional backup power systems.

Conclusion

Reliable backup power is essential for data centers to maintain uptime, protect data integrity, and comply with industry regulations. 

Diesel generators remain the industry standard, but natural gas, bi-fuel, and hydrogen fuel cell technologies are gaining traction. Proper generator sizing, redundancy planning, and compliance with environmental regulations are critical factors in selecting the right power solution.

As technology advances, innovations such as AI-driven maintenance, microgrids, and energy storage solutions will play a larger role in shaping the future of data center power reliability. 

Investing in the right backup generator ensures operational stability, protects against financial losses, and secures business continuity in an increasingly digital world.