Danfoss Turbocor and Haier build highly efficient air conditioning systems for KAI FU JIAN GUO hotel at Zhengzhou International Airport – China and save 1,500 CO2 emissions.
When it comes to energy consumption in hotel operations, air conditioning systems take a big part due to the long running times, that is, working 24 hours a day. Statistics show that it represents 30 to 50 percent of the hotel’s energy consumption.
For large hotels, air conditioning systems are more complex due to the huge volume of buildings, multifunctional areas as well as variable cooling load affected by occupancy rate, seasonal variations, daylight variations and others. factors.
How to respond to variations in the load of a hotel while being energy efficient has become a major issue in the design of air conditioning systems in large hotels. Therefore, from the very beginning of its construction, Zhengzhou KAI FU JIAN GUO Hotel was determined to seek a superior energy saving solution for hotel air conditioning systems.
Energy efficient and stable operation all year round
Opposite Zhengzhou International Airport, Zhengzhou KAI FU JIAN GUO Hotel is only a road width from the airport waiting hall and is the only five-star hotel in the airport area. The hotel covers an area of 90,000 m2 with a landscape style architecture, in which the main building has two floors and the annex building
five floors. It has 172 rooms, large and small meeting rooms, Chinese and Western restaurants, private compartments, recreation centers and a 460 m2 large ballroom.
The hotel building structure is lower than that of high rise buildings but over a larger area. Meanwhile, Zhengzhou’s climate is a typical continental monsoon climate characterized by an obvious seasonal and daily temperature difference.
The air conditioning system operates from April to September every year at partial load and only at peak load for one month between July and August, during which time the highest outside daytime temperature can reach 40 degrees Celsius. Finally, the water cooling unit solution with variable speed centrifugal compressor without magnetic oil jointly developed by the central air conditioning division of the Haier group with Danfoss Turbocor® compressors stood out from many other solutions.
IPLV encounter of 11.5
The hotel operates with two chillers which total 2110 kW of cooling capacity worldwide. Each chiller is fitted with two Danfoss Turbocor® TT400 inverter centrifugal compressors with oil-free magnetic bearings. Danfoss Turbocor® compressors use integrated variable speed technology with drive control.
When the condensing temperature and / or heat load changes, the cooling capacity can be adjusted to actual needs by the inverter, which regulates the speed of the compressor motor wheel. This reduces power consumption and improves the stability of the unit to ensure that the unit can run smoothly even under load conditions as low as 10 percent. The IPLV of the unit can reach 11.5 under partial load conditions. In compressors, traditional oil lubricated bearings are replaced by magnetic bearings.
Traditional oil lubricated bearing coolers can hamper heat transfer from heat exchangers and consume more energy due to the lubrication process. The ASHRAE research report shows that a cooling unit with every 3.5% increase in oil will consume 8% more electricity; Magnetic bearings help cooling units achieve the goal of 100% oil-free operation, allowing higher energy efficiency during unit operation.
Designed for endurance
The unit is designed with two compressors and both can operate independently. Before one of them reaches full load capacity, the other starts operating according to the left load, adjusts to the required capacity, and avoids full load operation of the first compressor. This unit design improves the life of compressors and
improves the overall security of the system.
CO² emissions reduced by 1,500 tonnes in 5 years
More than five years have passed since the unit was commissioned by the hotel in June 2008, and the air conditioning system is operating stably. “After a year, monitoring data showed that compared to traditional screw chillers, the variable speed centrifugal chiller had saved us around 50% energy. We are very
satisfied with its energy efficiency, ”said Mr. Ma, operations manager of KAI FU JIAN GUO Hotel Zhengzhou.
“Magnet variable speed central air conditioner also addresses the problem of constant and stable air conditioning operation under low load operating conditions,” he adds. “The monitoring data also shows that the current system using Turbocor inverter oil-free centrifugal compressors saves 300,000 kWh of electricity and up to 230,000 RMB in electricity costs per year compared to a unit equipped screw coolers. It reduces CO² emissions by around 300 tonnes per year ”.
The other fantastic news is that the energy efficiency of this chiller exceeds the efficiency of systems like water pumps. Usually, the energy consumption of cooling systems can be double that of water pump systems. According to measurements taken at the Kaifu Hotel, the energy consumption of these chillers is only half that of a traditional water pump system.
During the installation and operation period of the solution, the hotel management team and the system installation group measured other benefits with this oil-free magnetic bearing variable speed system. The size of the compressor is only half that of the screw machine, which saves a lot of space needed by air conditioners.
Besides the very low noise level and vibration-free operation of only 72dB, eliminate the need for insulation equipment and facilitate the construction of the unit, but also save system installation costs; the oil-free principle further saves on after-sales maintenance costs, which are expected to reach RMB 400,000 for the entire life cycle. These additional benefits were also recognized by the hotel management team.
For more information: email@example.com
Related links: http://cc.danfoss.com
Address reader inquiries to: firstname.lastname@example.org
Danfoss is a global leader focused on energy efficient solutions that save energy and costs, and reduce carbon emissions. The company’s wide range of products and services are used in areas such as food cooling, air conditioning, building heating, electric motor control and powering mobile machinery. The company is also active in solar and wind energy as well as district heating and cooling infrastructure for cities and urban communities. Danfoss was founded in 1933 in Nordborg, Denmark. Today, the Group employs around 23,000 people and sells its products in more than 100 countries around the world. Learn more about Danfoss at www.Danfoss.com. Discover its energy-efficient solutions on: http://www.danfoss.com/SolutionsReady/