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Unitary Air Conditioner Cost Estimator
UAC COST ESTIMATOR
Welcome to the Unitary Air Conditioner (UAC) energy and cost savings estimator.

This estimator simulates the energy usage of both a high efficiency and a standard efficiency air conditioner.  It then compares their energy and economic performance.

To run the estimator, characterize the two systems and their environment using the controls on this page.  Then click the 'submit' button.  Use your browser 'back' button to return from the results page to this control page.  Use the 'restore' button to change all values back to the defaults shown in the far right column.  Click here for help on printing.

Help on each control can be found by moving the mouse cursor over the question mark near the controls name; wait a second for the pop-up message to appear (Note: this help feature works best in the Microsoft Internet Explorer browser).  Click on the question mark to bring up a help window with more details.

Visit the engineering methods pages for additional background information on the UAC Cost Estimator. 		State State: this control affects the lists of cities appearing in the cities control. MO
City City: this value and the value in the state control are used together to collect weather data for this location. If your city is not listed, select the city whose climate is most similar yours (usually the closest city). Kansas City
Schedule Schedule: the air conditioner is assumed to be shut down (no run time) during hours outside of this schedule. M-Fri, 7a.m. to 7p.m.
Indoor Temperature Indoor Temperature: this is the thermostat set point. oF 75 oF
Total Capacity Total Capacity: select the ARI net cooling capacity of the equipment being used (or equivalently, the cooling load of the building). kBtuh in stages 84 kBtuh in 2 Stages
Oversizing Factor Oversizing Factor: percent that capacity exceeds load at design conditions. % 0%
Candidate Unit Candidate Unit: Energy Efficiency Ratio (EER), purchase and installation cost (k$), and annual maintenance costs ($/yr). EER  @  k$   $/yr 12 EER $4,500/unit $0/year
Standard Unit Standard Unit: Energy Efficiency Ratio (EER), purchase and installation cost (k$), and annual maintenance costs ($/yr). EER  @  k$   $/yr 9 EER* $4,000/unit $0/year
Enable Economizer Economizer: allows economizer to assist in meeting loads. Economizer enabled
Electric Utility Rate Electric Utility Rate: enter your local electric rate. If you do not know the rate, you can find it on your bill or call the local utility provider. $/kWhrs 0.08 $/kWhrs
Discount Rate Discount Rate: the rate ABOVE inflation (not the nominal discount rate that INCLUDES inflation). % 7.0 %
Equipment Life Equipment Life: number of years of life before equipment is replaced. years 15 years
Number of Units Number of Units: this is a simple multiplication factor used in calculating costs for a group of units. units 1 unit
Chart present value Chart present value: Displays the present value of purchase and operating costs (if unchecked, displays undiscounted costs). Chart present value
Show bin calculations Show bin calculations: Show the detailed calcs for each outside dry-bulb bin. Hide bin calcs
Version 3.1 Advanced controls Advanced controls: Unhide advanced controls (initialize them to their default values). Hidden

* equipment efficiency minimum federal level is 9.1.