Energy conservation

We recognize that the most effective way to reduce our greenhouse gas (GHG) emissions is to make our operations more efficient and thereby reduce our actual consumption of energy, which is IBM's most significant source of GHG emissions.

Energy consumption

In 2020, IBM consumed 3,513,000 megawatt-hours (MWh) of electricity and 605,000 MWh of fuel and other purchased energy commodities (e.g., chilled water, hot water and steam) worldwide. Our total energy consumption was reduced by 7.6 percent versus 2019. We estimate that 40 percent of our year-to-year reduction in energy consumption is attributable to lower office space utilization during the COVID-19 pandemic, while the remainder was due to our ongoing focus on operational efficiency and energy conservation.

Energy conservation projects

IBM implemented nearly 1,400 energy conservation projects at more than 230 locations globally during 2020. These projects delivered annual energy savings of 145,500 MWh, equal to 3.5 percent of our total energy use during 2020 and surpassing the corporate goal of 3 percent. They also avoided 51,000 metric tons of CO2 emissions and saved $15.4 million in expense. The avoided emissions were equivalent to removing more than 11,000 passenger vehicles from the road during the year.

In measuring performance against IBM's energy conservation goal, we only include the first year's savings from projects. Accordingly, IBM's total energy savings and CO2 emissions avoidance from these projects are greater than this simple summation of the annual results. We do not include reductions in energy consumption resulting from downsizings, the sale of operations or cost-avoidance actions, such as fuel switching and off-peak load shifting, in our energy conservation results.

When most of our workforce started working remotely due to COVID-19, our Global Real Estate organization acted swiftly to adjust lighting, temperature and other building systems schedules to avoid unnecessary consumption of energy. These actions significantly contributed to our 2020 energy conservation savings that came from measures related to heating, ventilation and air conditioning (41 percent of the total amount conserved). In addition, we implemented projects in our data centers, improving energy efficiency of both cooling and the IT equipment used, and contributing to 35 percent of the total amount conserved.

The remaining conservation savings were achieved across IBM's research, manufacturing and office space by implementing scheduled maintenance, lighting retrofits, and improving the operational efficiency of our building infrastructure. We have deployed IBM's IoT and analytics solution called IBM Smarter Buildings at 25 major IBM campuses covering 190 buildings and encompassing 41 percent of IBM's global energy consumption. During 2020, this program enabled the identification of energy conservation opportunities which resulted in the avoidance of 9,800 MWh of energy and $877,000 in expense.

From 1990 through 2020, IBM conserved 9.8 million MWh of energy, avoiding 4.6 million metric tons of CO2 emissions and saving $661 million.

Data center energy efficiency

IBM has a diverse portfolio of data centers supporting our clients and our internal operations worldwide. We take a holistic approach to managing and improving the energy efficiency of our data centers—from improving existing space to derive more workload per area; modernizing our IT infrastructure and reducing its energy consumption; to building or leasing new, higher-efficiency space.

Power Usage Effectiveness (PUE) is the ratio of the total energy consumed by the data center divided by the energy consumed by the IT equipment. The closer the value is to 1, the more efficient the cooling delivery. IBM calculates the PUE at many of the data centers we manage and obtains PUE data from landlords of co-location data centers. For data centers where we are unable to obtain PUE data, we use industry average data. Using this approach, we calculated our 2020 weighted average PUE to be 1.67.