Press Release Back Number(2006)

Joint development of the Smart Central high-efficiency central air-conditioning system
- Energy consumption cut approximately 20% from previous systems thanks to optimizing overall system control based on operational status of air-conditioning equipment -

February 6, 2006
Daikin Applied Systems Co., Ltd.
The Tokyo Electric Power Company, Inc.
Chubu Electric Power Co., Inc.
The Kansai Electric Power Company, Inc.

Daikin Applied Systems Co., Ltd., the Tokyo Electric Power Company, Inc., Chubu Electric Power Co., Inc., and the Kansai Electric Power Company, Inc. have announced the joint development of the Smart Central high-efficiency central air-conditioning system for midsized and large business facilities. The system will reduce energy consumption by some 20%*1 compared to previous systems. The improvements are based on efficient control of the entire system, based on assessments of the operating status of air-conditioning equipment*2.


Previous central air-conditioning systems were run by setting temperatures for heated and chilled water from heat-pump chillers*3 and for air-conditioning equipment, unit by unit. This led to insufficient coordination among air-conditioning units, as seen in heat pump chillers that operated around the clock to supply heated and chilled water at the configured temperature, regardless of the operating status of the air-conditioning equipment.


This Smart Central system achieves optimal control of the entire system based on a newly developed System Control Unit, embedded in heat pump chillers, that communicates directly with air-conditioning equipment, controlling heat pump chillers and hot- and cold-water pumps*4 based on the operating status of the air-conditioning equipment.


The Smart Central system provides the following advantages:


(1) Optimal control of the entire system reduces energy consumption by approximately 20%.

The System Control Unit automatically controls the following three facets of operations, making it possible to use approximately 20% less energy than previous systems:


  1. (i) Controls the number of heat pump chillers operating at any given time to achieve the most efficient load
  2. (ii) Controls the temperatures of heated and chilled water from heat-pump chillers based on the operating status of air-conditioning equipment
  3. (iii) Controls the volume of water sent to hot- and cold-water pumps based on the volume of hot or cold water needed

(2) Reduces initial costs by approximately 10%

By embedding into each unit or eliminating the measurement devices and controllers, the new system cuts the need to separately install the measurement devices and controllers for individual heat pump chillers, hot- and cold-water pumps and air-conditioning units. In addition, this system integrates the hot- and cold-water pump with the heat pump chiller, thereby reducing installation costs and initial costs by approximately 10%*5 compared to previous equipment.


(3) Offers high reliability and expandability

The entire system is single-sourced from Daikin Applied Systems. This will ensure consistent system performance and eliminate interface issues related to the control of individual devices.
The system is easily connected to office building multi-air-conditioning systems (including Eco-Ice) offered by Daikin Industries, Ltd.


Daikin Applied Systems plans to launch system sales in fall 2006.


In advance of the sales launch, the system will be introduced at the HVAC&R Japan 2006 trade show (organized by the Japan Refrigeration and Air Conditioning Industry Association).*6 This event is scheduled for February 7-10.


Daikin Applied Systems, the Tokyo Electric Power Company, Chubu Electric Power, and the Kansai Electric Power Company will continue working to meet customer needs for lower energy costs through aggressive development efforts targeting high-efficiency, low-cost equipment.


*1 Energy consumption reduced by approximately 20% compared to previous systems:

Estimated energy consumption for previous air-conditioning systems (from Daikin Applied Systems): 343,000 kWh
Estimated energy consumption of the Smart Central system: 280,000 kWh
(343,000 kWh - 280,000 kWh)/343,000 kWh * 100 = 18.4%


Assumptions:
  • • Building size:
    Total floor area of 22,000 square meters;
    air-conditioned floor area of 15,000 square meters;
    12 above-ground floors;
    two basement levels
  • • Use:
    Offices
  • • Air-conditioning load:
    2300 kW (cooling), 1500 kW (heating)
  • • Operating hours:
    Cooling: 8:00 a.m. - 6:00 p.m. over an 86-day period from June through September
    Heating: 8:00 a.m. - 6:00 p.m. over an 82-day period from December through March
  • • Estimation method:
    Based on results of actual operational testing at approximately 1/30 capacity

*2 Air-conditioning equipment:

Refers to equipment that controls interior temperatures and humidity using heated and chilled water produced by heat pump chillers


*3 Heat pump chiller:

Device used to produce the heated and chilled water used by air-conditioning equipment at facilities such as office buildings and factories


*4 Hot- and cold-water pump:

Equipment used to transport heated and chilled water from the heat pump chiller to air-conditioning equipment


*5 Initial cost reductions of approximately 10%:

Item Previous
air-conditioning systems		 Smart Central
Heat-source and
auxiliary-equipment costs 		18/17 17/18
Air-conditioning equipment and
auxiliary-equipment costs 		27/28 27/28
Total installation costs 17 8
Other construction 38 37
Total (%) 100 89/91

Note: These comparisons are based on a total value of 100% for previous air-conditioning systems.


Assumptions:
  • • Building size:
    Total floor area of 22,000 square meters;
    air-conditioned floor area of 15,000 square meters;
    12 above-ground floors;
    two basement levels
  • • Air-conditioning load:
    2300 kW (cooling), 1500 kW (heating)
  • • Heat-source capacity:
    • • Previous air-conditioning systems:
      50 Hz: 2520 kW (cooling), 2680 kW (heating)
      60 Hz: 2400 kW (cooling), 2840 kW (heating)
    • • Smart Central:
      2300 kW (cooling), 2438 kW (heating)
  • • Number of air-conditioning units: 69

*6 HVAC&R Japan 2006:

HEATING, VENTILATING, AIR-CONDITIONING AND REFRIGERATING EXPO.

  • • Dates and times:
    10:00 a.m. - 5:00 p.m. (4:00 p.m. on final day), Tuesday, February 7 - Friday, February 10, 2006
  • • Venue:
    West Exhibition Hall (Halls 1 - 2), Tokyo International Exhibition Center (Tokyo Big Sight)
  • • Organizer:
    the Japan Refrigeration and Air Conditioning Industry Association (http://www.jraia.or.jp/)
  • • Admission:
    free of charge (registration required)