The following are text extracts from the IBM "Tucson Dedication 1980" booklet.
The task of building a major manufacturing/development complex in the middle of the Arizona desert magnified the challenge of IBM's commitment to energy and resource conservation.
At the heart of the site's energy management system is an IBM Series/1 computer, which controls building temperatures, lighting, and water usage throughout the complex. This computer is connected to an on-site weather station to collect and process data on wind velocity, temperature, barometric pressure and other indicators. Based on these external factors, the system automatically adjusts internal environmental controls. Sensors installed in strategic locations around the site help ensure building-by-building consistency.
The hot dry climate demands that the site be primarily a cooling plant. Electrical energy is used as the basic power source for cooling. Water is chilled at night and then stored for use the following day to cool the air distributed to work areas. By running the chillers during the off-peak nighttime hours, the equipment can operate at maximum efficiency and at minimum cost.
Day-to-day operations of the site produce ample waste heat to meet most heating requirements. Even heat generated by computers is captured and stored for use later.
An interesting feature of the heating and cooling system [HVAC] is a process known as "economizer cycle air handling." Controlled by the computer, this process uses outside air, depending on the time of day, much the same as you might open windows in your house to bring in the cool air of a summer morning. The computer regulates air handling instantaneously and with a degree of accuracy conventional controls can't match.
The same careful attention devoted to energy conservation is given to water management. The site relies on its own wells for water. The complex is equipped with four water systems that stretch usage to the maximum. The site has its own wastewater treatment systems that provide the capacity for recycling. Sanitary wastewater is treated and stored for reuse in flushing toilets, saving roughly 50,000 gallons of water a day. Also, as much as 100,000 gallons a day of this same wastewater can be used for irrigation. Industrial wastewater is similarly recycled to the air conditioning system's cooling towers.
An important feature of the entire wastewater treatment design is that there is no discharge outside the site. Heavy waste solutions from the industrial waste treatment plant will be further concentrated by solar evaporation ponds after being treated so as not to pollute the air. Great care has been taken to prevent any seepage into the underground water supply.
In sum, the site's advanced energy and resource conservation design is a demonstration of what planning and commitment can achieve. That achievement will attest to IBM's environmental and energy consciousness for many years to come.