Energy is extracted from sewage and wastewater... Including ‘renewable energy sources’

In the future, heat from discarded water such as sewage and wastewater will be recognized as renewable energy and can be used for heating and cooling.

The Ministry of Climate, Energy and Environment announced that the amendment to the Enforcement Decree of the Renewable Energy Act, which expands the types of hydrothermal energy sources, was approved at the Cabinet meeting on the 10th and will take effect on the 17th.

Among renewable energy sources, only the 'surface layer of seawater' and river water were defined as hydrothermal energy, but this time, 'energy obtained by converting the heat of water determined and announced by the Minister of Climate Change in consideration of the appropriateness of water temperature and stability of water quantity, etc.' was added.

In line with this, the Ministry of Climate Change plans to enact a notification adding groundwater, sewage, sewage treatment water, wastewater, wastewater treatment water, reprocessed sewage and wastewater treatment water, and industrial water as hydrothermal energy.

Hydrothermal energy is generated from the temperature difference between water and air. Water's specific heat is four times that of air, and its temperature changes relatively slowly, making it colder than air in the summer and warmer in the winter. Because of this, hydrothermal energy can be used for cooling in the summer and heating in the winter.

The Ministry of Climate Change explained that it was now possible to obtain enormous energy from ‘wasted water’.

For example, by utilizing 20.9 million tons of effluent discharged daily from sewage treatment plants with a daily treatment capacity of 500 tons or more, 3 million Gcal (gigacalories) of energy, enough to heat 3 million households, can be obtained every month.

The Ministry of Climate Change has decided to additionally discover, designate, and manage hydrothermal energy.