In an era where environmental consciousness is not just a corporate social responsibility but a business imperative, sustainable IT is in the solar-powered spotlight. As companies seek to reduce their carbon footprints, the efficiency and longevity of IT infrastructure play a crucial role. One of the most underappreciated champions in sustainable IT is the mainframe.
Myth: Cloud Computing is More Energy Efficient
A common misconception about cloud computing is that it is inherently energy-efficient because resources can be turned on and off as needed. However, in reality, cloud servers are rarely turned off when not in use. Hyperscale cloud data centers maintain a persistent state of readiness, keeping resources available at all times, which leads to continuous energy consumption—even when workloads are idle. The on-demand nature of cloud computing primarily benefits cost savings rather than energy efficiency, as organizations only pay for the resources they actively use. Still, the underlying infrastructure remains powered and operational.
The Green Advantage of Mainframes
Unlike sprawling server farms that require vast amounts of power and cooling, mainframes are designed for high efficiency, consolidating workloads that would otherwise need thousands of x86 servers.
For example, IBM zSystems continue to push the boundaries of energy-efficient computing. The upcoming IBM Telum II processor and IBM Spyre Accelerator powering the next generation of IBM Z mainframes in 2025, are specifically designed to reduce AI-based energy consumption. These innovations include:
- A scalable IO sub-system that reduces data center energy consumption and cooling requirements.
- Telum II’s on-chip AI accelerators optimize power usage by minimizing data transfer overhead and improving system throughput, making them ideal for enterprise environments where energy efficiency is paramount.
- Iterative scaling for AI model development, where smaller models are combined instead of training large models from scratch, reducing computational costs by up to 50%.
Furthermore, IBM’s InstructLab initiative integrates AI with taxonomy-driven data curation to generate synthetic data, reducing the need for extensive manual datasets and lowering energy consumption in model training. IBM’s commitment to sustainability extends to its data centers, where 74% of its electricity consumption comes from renewable sources.
Financial Benefits of Green IT
Implementing greener IT practices can significantly reduce overall IT expenditures. Adopting energy-efficient hardware and virtualization technology can decrease energy consumption and result in substantial cost savings. VMware reports that virtualization can reduce the number of physical servers required and cut energy consumption by up to 80%
Organizations adopting the ISO 50001 energy management standard have also reported notable financial benefits. Sheffield Hallam University in the UK reduced its carbon emissions by 11%, yielding annual savings of over £100,000 (approximately $160,000). Additionally, a report by DNV indicates that 34% of businesses experienced cost savings from investments in supply chain sustainability. These findings illustrate that green IT initiatives contribute to environmental sustainability and offer tangible financial advantages.
34% of businesses experienced cost savings from supply chain sustainability investments
Hybrid Cloud and Sustainability
In an episode of The Main Scoop, Broadcom executives Greg Lotko and Barry Baker emphasize that hybrid cloud is a necessary enterprise strategy that balances functionality with energy use. Baker states, “Generation after generation, we continue to push the limits on how dense you can run that system, how much workload per kilowatt you can get out of the system. It’s performance, which is a big reason you think about hybrid cloud; it’s efficiency and lower power consumption, and it’s economics.”
From Broadcom’s perspective, hybrid cloud is essential because it allows businesses to choose the best environment for each workload—whether that’s on-premises, in a private cloud, or in a public cloud. They argue that companies should prioritize a “hybrid by design” approach, ensuring that workloads are optimally placed for both performance and sustainability.
Could “z” Also Stand for Zero Waste?
Recently, we interviewed Stuart Ashby, a mainframe expert, who suggests that the “z” in z/OS could–in addition to Zero Downtime–stand for “Zero Waste” due to the platform’s sustainability benefits. As Ashby notes, “Retail banks publicly say that the mainframe does more than 70% the amount of workload for less than 10% power consumption and less than 10% footprint.” This makes the mainframe a green option for production workloads.
Ashby also emphasizes the need for sustainable development and test environments, advocating for on-demand provisioning of resources to minimize energy waste. He highlights solutions such as Terraform scripts and PopUp Mainframe technology, which allow developers to create and delete development and test environments as needed, significantly reducing emissions and energy use.
The Future of Sustainable IT
Organizations eyeing sustainability must rethink their IT strategies. Here are key steps to optimizing IT sustainability:
- Assess energy consumption: Use tools like IBM’s hardware management console (HMC) to monitor power efficiency.
- Optimize workloads: Consolidate tasks onto fewer, more efficient machines, such as mainframes, and know how batch processing may impact energy consumption.
- Upgrade sensibly: Extend hardware lifespans to reduce e-waste from discarded electrical or electronic equipment, including working and broken items.
- Adopt greener power sources: Shift data centers to renewable energy sources where possible (both those owned by the organization and those of 3rd party cloud providers).
- Reduce redundancy: Minimize overprovisioning and eliminate unnecessary IT assets.
Commit to a Greener Future
By consuming less power, lasting longer, and requiring fewer resources for equivalent workloads, mainframes offer a stark relief to the energy-intensive, always-on, cloud computing model.
In an industry often plagued by greenwashing, tangible sustainability efforts like IBM’s recycling programs, workload consolidation, and AI-driven efficiency monitoring demonstrate that responsible IT infrastructure decisions can have a lasting impact. As Broadcom’s insights suggest, hybrid cloud strategies leveraging mainframes are critical for reducing energy consumption and ensuring a sustainable future.
Investing in mainframes isn’t just a smart IT move for companies serious about environmental responsibility; it can be part of a commitment to a greener future.
Amanda Hendley is the Managing Editor of Planet Mainframe and Co-host of the iTech-Ed Mainframe User Groups. She has always been a part of the technology community having spent eleven years at Technology Association of Georgia and six years at Computer Measurement Group. Amanda is a Georgia Tech graduate and enjoys spending her free time renovating homes and volunteering with SEGSPrescue.org in Atlanta, Georgia.