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Improve Power Usage Effectiveness (PUE) at Our Data Centers

Our Approach

With the spread of cloud computing, energy use by data centers is on an upward trend and society is showing more concern over the environmental performance of data centers. Data centers comprised 25% of FY 2017 CO2 emissions in the Fujitsu Group, with emission rates increasing by an annual average of 5.0% over the four years from FY 2013-17 at our 36 main data centers inside and outside Japan. Furthermore, our data center CO2 emissions are expected to continue to rise as our cloud business grows, making environmentally conscious data centers a social responsibility for the Group, as well as a critical theme to address in strengthening our business foundation over the long term. In the Fujitsu Group, we are targeting*1 approximately 80% of our data centers (based on server room floor space) and we are working to boost environmental performance.

*1 Activity targets:
Global data centers 1,000 m2 or larger, in principle, or specific data centers requested by data center business units.

FY 2017 Performance and Results

Summary of FY 2017 Achievements

Promoting Activities to Achieve the Targets

As part of activities based on the Fujitsu Environmental Action Plan, Fujitsu is moving forward with the improvement of PUE*2 at its data centers inside and outside Japan. PUE in FY 2017 was 1.60, slightly exceeding our target of 1.59. However, through primary initiatives including improving the cooling efficiency of air-conditioning systems, expanding the hours when external ventilation is used, and maximizing utilization of free cooling options, we achieved an average yearly improvement of approximately 2%.

We will continue to reduce the power used for facilities and ICT by making energy more efficient through improved operations and introduction of innovative technologies. Furthermore, we will strive to increase the use of renewable energy, aiming for a carbon-free society as stipulated in the Paris Agreement*3.

*2 PUE (Power Usage Effectiveness):
an indicator showing the energy saving performance of data centers. PUE is obtained by dividing the energy usage of an entire data center by the energy usage of its servers and other ICT equipment. A PUE closer to 1.0 indicates better energy efficiency.

*3 Paris Agreement:
A new framework for measures against global warming to reduce greenhouse gases through international cooperation, with more than 190 countries from the developed and developing world participating. It came into force in November 2016.

PUE Values and PUE Calculation Method

Main Activities of FY 2017

Air-conditioning Equipment Control through AI

Continuing from FY 2016, we worked to improve air-conditioning energy efficiency inside and outside Japan. We are improving efficiency through new technologies to achieve Environmental Action Plan (Stage VIII) targets.

For example, we reduced annual power consumption by 20% by using Fujitsu's innovative just-in-time modeling air-conditioning controls, predicting temperatures and humidity an hour ahead from temperature, humidity, and power data for outside air environment and inside servers, and then controlling outside air cooling and air-conditioning equipment air temperature. Moreover, we plan to further expand the control area. We are also currently verifying AI-driven learning control technology. We are improving power efficiency for air conditioning by modeling optimal air conditioning properties based on factors including wind volume, processing heat, and ICT device load. Moving forward, we will utilize the effectiveness of these measures to enable control of cold/heat-source facilities such as chillers and cold-water pumps.

Air-conditioning Equipment Control through AI

Improved Operation through Development of a Data Center Evaluation Tool

At the Fujitsu data center located in Tochigi Prefecture, as a method of evaluating whether or not the cooling energy of ICT devices is being efficiently operated and controlled, we conducted analysis based on the heat balance and airflow balance. During analysis, we ascertained the energy reduction potential amount from the current structure and facilities specifications of the data center. We then developed a "data center evaluation tool" capable of calculating the theoretical PUE value which can be achieved through improvements.

Using the tool makes it possible to analyze the necessity of implementing high-efficiency facilities by visualizing energy loss and proposing optimal related measures. Based on the analysis results, we are working to clarify policies for improving data center operation and achieving even greater efficiency. Also, in order to realize even smoother improvements, we are planning to create guidelines based on expertise gained from evaluation methods and different data centers. We will then make these guidelines available throughout the Fujitsu Group.

Data Center Evaluation information

Expanded Use of Renewable Energy

In May 2017, we announced our company's Environmental Vision for the achievement of a low-carbon society. We are taking steps to systematically transition to renewable energy for the power used by our data centers. In particular, the shift to renewable energy is proceeding with a focus on overseas, where it is possible to procure green energy. Renewable energy now accounts for 17% of the total power used at our 36 main data centers inside and outside Japan.

Almost all of our data centers using renewable energy are located overseas. We will work to actively expand the use of renewable energy from our overseas sites.