Tap water heating in the Antarctic
Scott Base, Antarctic (NZ)
The Antarctic is the driest, coldest and windiest conti
nent in the world. In July 1983, the lowest recorded temperature on the earth’s surface was measured at -89.2ºC. Scott Base, opened in 1957, is one of the first research bases established in the Antarctic and houses up to 85 scientists.
Indoor heating for the base uses energy rec
overed by Alfa Laval heat exchangers from the power generation plant. This maintains a heating loop through the base at 60-70°C. Indoor temperatures at the base are
typically set at 18°C for reasons of energy conservation.
Tap water heating
Fresh tap water is produced at the rate of 8,000 litres per day by a reverse osmosis plant. 140,000 litres of tap water, kept in four insulated tanks, is kept from freezing by continually circulating it back to the powerhouse. There it passes through an Alfa Laval plate heat exchanger attached to the heating loop. Other plate heat exchangers connected to the loop provide a steady supply of hot tap water for the kitchen and bath facilities.
Plate heat exchangers
Thanks to the various heat exchangers, the critical indoor heating and tap water heating at Scott Base can be resolved in the most energy-efficient and reliable way, despite the adverse Antarctic climate.
Facts and figures
A sophisticated heat exchanger solution saves
energy in New York
Combining energy-efficient technologies, New York
The Bank of America Tower in midtown Manhattan - a LEED certified building features some of the most sophisticated heating and air conditioning equipment in the world. Among many sustainable and energy-efficient solutions, the building uses Alfa Laval heat exchangers for free cooling, ice thermal storage and combined heat and power generation. The heat exchangers operate in close conjunction with an absorbtion chiller located three stories below ground.
Free cooling and thermal ice storage
During the five months of the year when outside temperatures are low enough, a cooling tower produces chilled water for cooling purposes. Alfa Laval plate heat exchangers transfer the free cool to the air conditioning system. No or very little mechanical refrigeration is required, which cuts the use of electricity dramatically. In summer, the system switches to an ice thermal storage solution. At night, when the price of energy is low, the absorption chiller cools a closed ethylene glycol loop, which produces ice for storage in huge tanks. During daytime, the cycle is reversed and water from the melting ice is used to cool the building’s air conditioning system. Alfa Laval plate heat exchangers are used to separate the glycol, water and air conditioning loops.
Heat recovery in a combined heat and power plant
The building is also equipped with a combined heat and power plant that uses Alfa Laval heat exchangers to distribute the heat throughout the entire building, while generating 75 percent of the total electricity used. The hot exhaust gas from a turbine engine is recovered in a boiler that produces steam. The turbine generates electricity, while the steam is used to heat the building during winter and to run the absorption chiller during the rest of the year.
Substantial energy savings
By combining three modern technologies – free cooling, ice thermal storage and combined heat and power generation, Bank of America greatly reduces its use of energy and emissions of CO2. As an example, the heat recovery system is able to capture 70% of the energy contained in the natural gas used – compared to only 30% in a typical utility plant.
Facts and figures:
• 13 AQ10 Gasketed Plate Heat Exchangers
• 2 AQ8 Gasketed Plate Heat Exchangers
• 11 AQ6 Gasketed Plate Heat Exchangers
• 1 AQ4L Gasketed Plate Heat Exchangers
• 2 CB76 Copper Brazed Heat Exchangers
Design pressure is up to 33 bar (480 psi).