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Hydrothermal Energy, the Infinite Source of Clean Energy
Hydrothermal energy refers to heat energy produced from hydrothermal heat, which is used for cooling or heating. Recently, Korea with its abundant stream water and sea water, Korea has recently been stepping up efforts to develop hydrothermal energy. Hydrothermal energy is renewable, and supply is stable. For this reason, hydrothermal energy is quickly emerging as an effective renewable energy.
Text by the Editorial Team Source: Climate Change & Carbon-Neutral Business Department of K-water
Hydrothermal Energy, an Eco-Friendly Energy from Water
The data industry is expanding fast as a core industry holding the key to national competitiveness. There is also a rapidly growing demand for data centers to process increasing amounts of data, a key ingredient of digital technology and AI. Data centers consume large quantities of electricity to cool heated servers running 24/7. An overheated server can stop operating, cause fire, or pose other risks. As using less energy for cooling emerges as a key competitive factor for data centers, hydrothermal energy is coming into focus as an eco-friendly energy that can reduce both power consumption and carbon emissions at the same time.
Why do people go to beaches and valleys to get away in the heat of summer? It is cooler in water than on land. Water remains relatively cool even when the temperature rises in summer. Specific heat refers to the quantity of heat required to raise the temperature of a substance by one degree Celsius. The specific heat of water is greater than that of air or dry soil. This is why water heats up and cools down more slowly than land. In other words, water is cooler in summer and warmer in winter than air. Such particular property of water is used to generate hydrothermal energy. The heat energy of water is transmitted through heat pumps to buildings for cooling and heating.
Hydrothermal energy is derived from water, which means we can get limitless energy through a natural process. Unlike other renewable energy sources, hydrothermal energy generation is less affected by weather conditions and remains stable in supply. According to an analysis, Lotte World Tower can save energy by around 35% by using hydrothermal energy and reduce greenhouse gas emissions by approximately 38% compared to using fossil fuels. In addition, using hydrothermal energy can alleviate the effects of the urban heat island phenomenon; thus contributing to responding to climate crisis caused by global warming.
Hydrothermal Energy, the Key to Carbon Neutrality: Success Cases
Countries around the world are keenly interested in hydrothermal energy. Stream water and deep lake water stagnating under the banks of dams or lakes are used to produce hydrothermal heat, which is then used to heat or cool buildings. A major case in point is City-Zen, a zero-carbon city project launched in the Netherlands. In the project, river water drawn from canals, surface water, or wastewater is used to produce hydrothermal heat. Buildings along the canal in Amsterdam, the capital of the Netherlands, use the heat generated from groundwater for cooling and heating. In particular, the city of Limburg, a new town in the east, has been using only renewable energy including hydrothermal energy for power supply to heat and cool buildings since the first phase of the project, which started in the early 2000s.
France is also actively encouraging the use of hydrothermal energy to mitigate the effects of the urban heat island phenomenon. As part of such efforts, France created a 75km-long urban hydrothermal heat supply network using water from Seine River in 1991, and around 700 buildings including the Louvre and department stores are using hydrothermal energy for cooling and heating. The city of Paris is planning to expand the hydrothermal energy system by more than three times by 2041 and to use hydrothermal energy at the 2024 Paris Olympics main stadium and Olympic Village. The AliCloud Qiandao Lake Data Center of the Alibaba Group, China’s leading IT company, has been running a cooling system designed with the use of water from Qiandao Lake since 2015.
The Korean government listed hydrothermal energy as new renewable energy in 2015, and the scope of its applications has been further expanded with the inclusion of stream water in the list of sources of hydrothermal energy in addition to sea water from the surface zone in October 2019. In this context, the Ministry of Environment is implementing the Pilot Project for the Promotion of and Support for Hydrothermal Energy financed with the central government budget in order to encourage the use of hydrothermal energy. Introducing hydrothermal energy to local governments, public organizations, and buildings owned by private companies under the project can reduce electricity use by 16GWh and greenhouse gas emissions by 8,000 tons per year, which is equivalent to planting 1.4 million pine trees.
What is K-water Doing to Promote the Use of Hydrothermal Energy?
As the country’s leading and only water management organization, K-water started to use hydrothermal energy at its business sites in 2006, having laid the groundwork for hydrothermal energy projects while successfully carrying out government-led pilot projects. Lotte World Tower Jamsil, the tallest building in Korea with 123 floors aboveground rising 555m, uses hydrothermal energy generated with the use of water from Hangang River. Hydrothermal energy from water in Paldang Dam is used to cool and heat the building. Hydrothermal energy accounts for around 10% of all the electricity consumed for heating and cooling of the building, cutting annual energy spending by 35.8% or KRW 700 million.
K-water is also pushing ahead with a project to create the Gangwon Hydrothermal Energy Cluster designed to produce hydrothermal energy from deep water drawn from Soyanggang Dam and use it to cool data centers in the era of the 4th Industrial Revolution. The groundbreaking ceremony for the cluster was held in March. The project includes the creation of a mega-size eco-friendly data center, a hi-tech smart farm-based agricultural complex, and a data industry integration valley with the use of deep water from Soyanggang Dam whose temperature remains at 7℃ throughout the year, on an 810,000㎡ area in Dong-myeon, Chuncheon. With the opening of the cluster, Chuncheon is expected to emerge as the capital of Korea’s data industry and a regional stronghold of the global data industry.
In the same vein, Pangyo Techno Valley, one of Korea’s key IT centers, is also embracing hydrothermal energy under the “Pangyo 641 Project” wherein hydrothermal energy will be generated using raw water drawn from the Paldang Water Intake Station, which is running in the pipes of the metropolitan water supply network, to reduce electricity consumption and greenhouse gas emissions.
Since water is the source, hydrothermal energy can be produced sustainably and supplied stably. With strong water resources infrastructure in place, Korea is well-poised to maximize the benefits of hydrothermal energy. Expectations remain high for the limitless energy source of water and the growth potential of hydrothermal energy.
