In tandem with the development of Minato Mirai 21 District, MM21 DHC expanded and upgraded the heating and cooling equipment at both plants to improve its supply capacity.
Plant capacity
| Cooling capacity | Heating capacity | |
|---|---|---|
| Center Plant | 25,518RT | 165.5 t/h |
| No. 2 Plant | 52,000RT | 148.0 t/h |
| Total | 77,518RT | 313.5 t/h |
Large-scale Ice Storage System
MM21 DHC operates a large-scale system for ice thermal storage, a form of latent heat storage (LHS). Ice storage tanks are filled with about six million water-filled plastic balls (about 77 mm in diameter) called nodules, which are frozen to store energy for heating and cooling.
This system is installed at Center Plant and has a storage capacity of 30,000 RT. When dissipating heat, it can deliver up to 5,000 RT for 6 hours.
At night, when power demand is low, chillers are operated to store thermal energy. The cold energy stored at night is released during the day, reducing peak energy demand in the summer and the cost of heat energy generation.
Inverter centrifugal chillers
Each plant uses two inverter centrifugal chillers that are one of the world’s largest inverter centrifugal chillers (5,400 RT), with a cooling capacity equivalent to approximately 5,400 residential air conditioners designed for 12-tatami rooms (18.5 sqm).
By controlling the rotational speed of compressors and pumps with inverters, the system achieves a high coefficient of performance (COP) of up to 24.3. This means it can deliver up to 24.3 times the energy required to operate the equipment, significantly reducing power consumption during periods of low demand, such as mid-season and winter.
This system serves heating and cooling demand year-round and contributes to improvement of plant efficiency.
Other main equipment
