2017.03.14
EBARA Corporation
EBARA Refrigeration Systems Corporation
Development of Gas-Fired Absorption Chiller-Heaters that Save Energy - Halving Startup and Shutdown Times and Energy Consumption that Have Been Overlooked
EBARA REFRIGERATION SYSTEMS CORPORATION (ERS), a member of the EBARA Group, and Chubu Electric Power Co. (Chubu Electric Power Co., Inc.) have jointly developed a gas-fired absorption chiller/heater*1 equipped with a control method that can *2 halve the startup time and energy consumption of gas-fired absorption chiller/heaters.
Gas-fired absorption chiller/heaters have the disadvantage of long startup time. Therefore, the dilution operation*3 during shutdown, which is the main cause of long startup time, has been improved to minimize it based on the operating conditions, and a control method has been developed to increase the heat input to the gas-fired absorption chiller immediately after startup by reviewing the combustion volume control during startup. The control method to increase the heat input to the gas-fired absorption chiller/heater immediately after startup was developed. Gas-fired absorption chiller/heaters equipped with this control have achieved a reduction of half the time and energy required for startup compared to conventional control methods.
This newly developed machine will be released by ERS in April this year.
Features of the gas-fired absorption chiller/heater developed
- 1 Halves startup time and energy consumption
Startup time, which previously took 20 to 30 minutes, is halved to 10 to 15 minutes.
Halves startup time from 20 to 30 minutes to 10 to 15 minutes. This enables a quick response to chilled water demand similar to that of electric chillers, while also halving energy consumption for startup and shutdown. - 2 Can also be installed in conventional units
This control can also be installed in some existing ERS gas-fired absorption chillers.
Since this control can also be installed in some existing ERS gas-fired absorption chiller/heaters*4, it contributes to energy savings for customers who have already sold gas-fired absorption chiller/heaters.
* 1 Gas-fired absorption chiller/heater
A chiller that produces chilled water by absorbing refrigerant (water) into an absorption solution, without using a compressor. Heat from gas combustion is used to separate water, increase the concentration of the absorption solution, and restore (regenerate) the absorption capacity. It is also possible to use the heat from gas combustion as a heating source to produce hot water for heating.
* 2 Halves startup time and energy consumption
If the refrigeration load factor at the last shutdown is approximately 70% or less, the startup time and energy consumption can be halved. Note that the reduction rate of startup time depends on the refrigeration load factor at the time of the last shutdown.
* 3 Dilution operation during shutdown
In gas-fired absorption chiller/heaters, dilution operation is performed to dilute the highly concentrated absorption solution during shutdown to prevent crystallization of the highly concentrated absorption solution produced in a room called the regenerator as its temperature drops during shutdown. During startup, the diluted absorption solution must be re-concentrated, which is the main reason for the long startup time of gas-fired absorption chiller/heaters. In order to prevent water from freezing during dilution operation, not only the pump inside the gas-fired absorption chiller but also the water pump outside the machine must be operated.
* 4 This control can also be installed in some existing ERS gas-fired absorption chillers
A modification to add this control to some existing ERS gas-fired absorption chillers will be available upon request from September of this year for a fee. The models that can be modified to add this function starting this September are the RCD type (models whose name starts with RCD that started production in 1997), the RED type (models whose name starts with RED that started production in 2000), and the RGD type (models whose name starts with RGD that started production in 2008). Supported models will be expanded sequentially. Adding this function requires the addition of control equipment to the gas-fired absorption chiller/heater and modification of the electrical system.
* Note: "XXX type" is our model symbol.
[Inquiries about new products and products already on the market]
Planning and Administration Section, Domestic Business Management Department, EBARA Refrigeration Equipment & Systems Corporation (03)6384-8080 (main)
[Inquiries about the contents of the announcement]
Planning and Administration Section, Domestic Business Management Department, EBARA Refrigeration Equipment & Systems Co. Public Relations Department, Public Relations Group, Chubu Electric Power Company (052) 961-3582
Development System / Development Period
1 Development Structure
EBARA Refrigeration Systems Corporation
Address: 3-2-16 Omori-Kita, Ota-ku, Tokyo
Representative Director: Kanjin Ge
Chubu Electric Power Company
Address: 1 Higashishinmachi, Higashi-ku, Nagoya City, Aichi Prefecture
President: Satoshi Katsuno
2 Development Period
April 2016 - March 2017
Development Overview
1 Development aircraft exterior view

2 Control Overview and Effects


* 1 Example of stopping and starting at rated refrigeration capacity of 527 kW and refrigeration load factor of 55%. The value of the effect varies depending on the model and shutdown conditions.
* 2 Total power consumption of gas-fired absorption chiller/heaters, chilled water pumps, cooling water pumps, and cooling towers.
* 3 Primary energy conversion values are estimated using 9.76 MJ/kWh for electricity and 45 MJ/m3N for gas.
* 4 Electricity and gas rates are estimated at 17.96 yen/kWh and 91.05 yen/m3N, respectively.