The Carbon Footprint in the Age of AI: The Invisible Energy Cycle Beyond the Cloud

Every time a question is posed to ChatGPT, a massive data center consumes power behind the scenes. This is the reality we face in 2025.

The Reality of Invisible Power Consumption

According to a report released by the International Energy Agency (IEA) in April 2025, the global power consumption of data centers is expected to reach approximately 415 TWh by 2024, accounting for about 1.5% of global power consumption, with a rapid average increase of 12% over the past five years. It is projected that by 2030, the power consumption of data centers will exceed double the current level, reaching 945 TWh.

Korea IDC recently analyzed that the domestic data center power demand will increase by more than 40% from 4,461 MW in 2024 to 6,175 MW in 2028. This is due to the significant increase in power consumption based on high-performance servers driven by the spread of generative AI.

The problem is that this energy consumption is 'invisible.' We only see the smartphone screen and are unaware of the physical infrastructure behind it.

Transition to Renewable Energy: Between Reality and Goals

According to a report released by the Green Transition Research Institute in September 2025, the power usage efficiency (PUE) of six major domestic IT companies ranges from 1.2 to 1.49, which is higher than global companies like Google (1.09) and Microsoft (1.18). PUE is the ratio of total power consumption of the data center to the power consumption of IT equipment, meaning that a lower value indicates higher efficiency.

As of 2023, the proportion of renewable energy used by major domestic IT companies is only 3% for Naver, 1.3% for Kakao, 5.2% for SK Telecom, 0.004% for LG Uplus, and 0.03% for KT, averaging just 1.9%.

Naver announced that it will convert all the power it uses to renewable energy by 2040, and Kakao has also joined RE100. Naver is expanding its use of renewable energy by establishing solar power facilities at its Chuncheon and Sejong data centers and using stored rainwater for landscaping.

However, the reality is challenging. Kakao and Samsung SDS stated, "We are trying to increase the proportion of renewable energy use, but it is difficult to procure under domestic conditions."

The Global Trend of Transition

The IEA predicts that renewable energy will account for about half of the additional power demand from data centers by 2030. Renewable energy is expected to record an average annual growth rate of 22% in generation from 2024 to 2030, becoming the fastest-growing source for power supply to data centers.

Google plans to convert 100% of the power used in its global data centers to renewable energy by 2030. Microsoft has set a goal to supply 100% of the power for all its data centers with renewable energy by 2025.

Finding Efficiency Through Technological Innovation

The IEA report analyzes that hardware technology is advancing to reduce unnecessary power consumption when equipment is not performing actual tasks, as the idle power ratio of servers decreases.

Google has reduced cooling power consumption by an average of 30% using AI, and Microsoft has improved water usage efficiency (WUE) from 0.49 to 0.30 L/kWh, a 39% improvement, by introducing waterless immersion cooling.

SK Hynix is contributing to improving energy efficiency in data centers by developing low-power memory HBM and high-capacity eSSD for AI servers.

Improving just the cooling system can have a significant impact. Chinese companies like Alibaba and Tencent are adopting cutting-edge efficiency technologies such as single-phase immersion cooling, intelligent energy management systems, and modular power supplies to comply with government power efficiency regulations.

The Reality in Korea

Power experts analyze that to meet the annual increase of over 400 MW in data center power demand solely with renewable energy, more than 3 GW of new installations are needed each year based on solar power.

However, the average new solar installation capacity in Korea over the past three years has been around 2 GW, and at the current pace, it is realistically difficult to cover even 30-40% of the increase with renewable energy by 2028.

The Ministry of Trade, Industry and Energy has proposed activating distributed energy and improving data center energy efficiency as policy tasks by July 2025, but location regulations and delays in grid connections are acting as bottlenecks.

An industry insider lamented, "We need power, but there is no transmission network, and if we build, there is local opposition and regulations are increasing." He added, "Data centers based on renewable energy are significantly costly and time-consuming in Korea."

When the Invisible Starts to Become Visible

The IEA predicts that renewable energy will account for the largest share in meeting data center power demand, reflecting the broad accessibility of renewable energy, short development periods, economic competitiveness, and the power purchasing strategies of tech companies.

AI will not stop. Therefore, the choice we can make is 'how does AI operate?' There is physical infrastructure beyond the cloud, consuming energy, and we must consider the source of that energy. The cycle that was once invisible is now beginning to be seen.