The Ultimate Guide to Commercial Chiller Selection
CogenS™ – Hydronics MFG Selector
Optimizing for Lifecycle Value, Not Just First Cost
A chiller is a powerful heart of a commercial building’s cooling system and, without question, its single largest consumer of electricity. The decision of which chiller to install is a multi-decade commitment that has a greater impact on a building’s operational budget and carbon footprint than nearly any other piece of equipment.
Yet, too often, this critical decision is driven by the lowest upfront price—a short-sighted approach that ignores the true total cost of ownership (TCO). An inefficient chiller, even one with an attractive initial cost, can bleed a facility’s budget through excessive energy consumption and high maintenance expenses for years to come.
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Effortless Software for a Complex Problem
Objectively Evaluate, Model and Select between Multiple
Chiller System Vendor Products
CogenS™ – Hydronics MFG Selector is an advanced technoeconomic modeling tool engineered to prevent these costly errors. It empowers mechanical engineers, facility managers, and building owners to move beyond the spec sheet and conduct a rigorous, data-driven analysis of multiple chiller manufacturers, ensuring the final selection delivers the best possible performance and financial return over its entire lifecycle.
What is CogenS™ - Hydronics MFG Selector?
CogenS™ is a powerful, unbiased modeling platform that allows users to run multi-scenario technoeconomic analyses across a range of chiller manufacturers and technologies. By inputting your project’s specific data—including building load profiles, local weather files, and complex utility tariff structures—you can simulate how different chillers would perform in your real-world environment.
The tool processes these inputs to deliver clear, actionable outputs, including:
A ranked selection of options based on the lowest Total Cost of Ownership.
Detailed annual energy consumption and cost projections.
Carbon emissions profiles to support sustainability and ESG reporting.
Key financial metrics like Net Present Value (NPV) and Internal Rate of Return (IRR).
CogenS™ removes the need for complex, error-prone spreadsheets, providing a standardized and defensible method for making high-stakes procurement decisions.
How It Works
Upload your facility's cooling load profiles, local utility rates, and climate data to create a detailed digital twin of your operating environment.
Input the technical data from all chiller vendors under consideration, including full- and part-load efficiency curves (IPLV/NPLV), maintenance schedules, and capital costs.
The tool simulates each manufacturer's system across the entire project lifecycle, using consistent conditions for a fair, data-driven comparison.
Instantly view tabulated results comparing TCO, energy use, emissions, and financial returns. Identify the most efficient and financially sound system with confidence.
Technical Specifications
Air-cooled and water-cooled chillers
Centrifugal, screw, scroll, and absorption chillers
Electric-driven and gas-driven chillers
Single-unit and modular chiller plants
Cooling Load Profiles: Hourly/sub-hourly building cooling demand
Weather Data: TMY3 or custom climate files
Utility Rates: Electricity tariffs, TOU, and peak demand charges
Chiller Manufacturer Data:
COP or EER at full and part load
IPLV/NPLV values
Ramp rate and part-load degradation
Maintenance cycle and service life
Startup, idle, and standby consumption
CAPEX and OPEX profiles
Refrigerant type and emissions data
Up to 15
- Efficiency at part and full load
- Multi-unit operation
- Minimum part-load ratio
- Emissions and fuel use
- CAPEX and OPEX
Total Cost of Ownership (TOC): Over a user-defined horizon (10–30 years)
Annual Fuel and Energy Use: For electricity, gas, or hybrid configurations
Operating and Maintenance Costs: Based on usage and unit design
Carbon and Criteria Emissions: With optional carbon pricing
NPV, and IRR: Full financial metrics for decision-making
Degradation Impact: On performance and costs over time
Side-by-Side Comparison Table: Results for all manufacturers entered
Excel
Available via CogenS™ local install
CogenS™ Hydronics MFG Selector Project Design Process
Project Info
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Location.
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Building Type (Industrial, Commercial or Residential).
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Microgrid components (Combined Heat and Power, Combined Cooling Heat and Power, Energy Storage and PV).
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Modeling interval (15, 20, 30 and 60 minutes).
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Metric VS Imperial Units.
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Weather Data.
Energy Profiles
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Building energy profiles Estimation and Analysis (Electric, Gas, Oil, Cooling, Heating, Domestic Hot Water).
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Fuel specifications (Heating Value and Density).
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Scenario Analysis Option (Maximum, Average and Minimum Load Profiles)
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Peak, Minimum, Average Demand and Load Factor.
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Grid Emissions Factor.
Energy Cost
Electric and Gas Utility Tariff
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Fixed and minimum charges.
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Rates Escalation.
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Unlimited Energy and Demand charges by Period and Tier.
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5 Different Metering and Billing Types:
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Net Energy Metering
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Net Energy Metering with $ Credits
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Net Billing
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Net Billing with Carry Over to next Month
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Buy All/Sell All
Oil Cost
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Fixed and minimum charges.
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Rates Escalation.
Cooling
Chillers
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Equipment modeling features:
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Screw, Centrifugal, Scroll and Reciprocating compressors.
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Water- or air-cooled condenser.
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Electric or Gas-Fired absorption.
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Indirect Hot Water or Steam absorption.
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System modelling features:
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Identical multi-unit system.
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Variable or Constant Flow.
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Supply Temperature Reset.
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Part-Load Efficiency Performance.
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Optimized number of operating units.
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CO2e emissions.
Cooling Towers
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Equipment modeling features:
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Open or closed loop.
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Cross or Counter flow.
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Single, 2-speed or variable speed fan.
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System modelling features:
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Identical multi-unit system.
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Free Cooling Heat Exchanger option.
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Wet-Bulb Reset Control Scheme.
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Variable or Constant Flow.
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Supply Temperature Reset.
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CoolTools or YorkCalc Heat Rejection Performance.
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Optimized number of operating units.
Results
Summary
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Energy, Financial and Emissions savings.
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Financial KPIs
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Project Capital and Operating Activities pie charts.
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Conventional VS Cogeneration Pie charts:
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Energy Bill and Consumption by fuel.
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Gas Consumption by fuel.
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Electricity production and emissions by equipment.
Tables
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Lifetime profiles for key project variables in tabular format:
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Sub hourly
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Hourly
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Daily
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Weekly
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Monthly
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Yearly
Plots
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Lifetime profiles for key project variables in plot format:
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Sub hourly
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Hourly
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Daily
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Weekly
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Monthly
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Yearly
Core Benefits at a Glance
Why use CogenS™ for your next Chiller procurement decision?
Who Should Use It?
This modeling platform is indispensable for any professional involved in the design, purchase, or management of chiller systems.
Move beyond basic compliance and deliver true value engineering. Use CogenS™ to validate your HVAC system design, compare technologies (e.g., air-cooled vs. water-cooled, centrifugal vs. magnetic bearing), and provide clients with a clear, data-backed recommendation for chiller plant optimization.
Make an ironclad business case for capital expenditures. Justify chiller retrofits and replacements with detailed ROI projections that show the long-term savings from investing in high-efficiency equipment.
Conduct sophisticated energy audits and develop performance contracts with unparalleled accuracy. Use CogenS™ reports to validate projected energy savings and secure project financing.
Differentiate your bids by offering a sophisticated total cost of ownership analysis. Build trust and win more projects by demonstrating long-term value to your clients.
Protect your investment by ensuring the mechanical systems in your portfolio are optimized for low operational costs and long-term sustainability, making your properties more valuable and marketable.
Food for thought Why a Data-Driven Approach to Chiller Selection is Critical
In today’s economic and regulatory climate, selecting the right chiller requires a level of analysis that goes far beyond simple payback calculations. A truly optimized choice must account for real-world performance, fluctuating energy costs, and stringent efficiency standards.
The Critical Importance of Part-Load Efficiency (IPLV/NPLV)
A chiller is sized to handle a building’s peak cooling load, a condition that occurs for less than 1% of its annual operating hours. For the other 99% of the time, the chiller runs at partial capacity. This is why part-load efficiency is the single most important metric for determining real-world energy consumption.
The industry standard for measuring this is the Integrated Part Load Value (IPLV), a rating established by the Air-Conditioning, Heating, and Refrigeration Institute (AHRI). It provides a weighted average of a chiller’s efficiency at 100%, 75%, 50%, and 25% loads. For projects with unique operating conditions, a Non-Standard Part Load Value (NPLV) provides an even more accurate picture. A tool that can accurately model performance using these values is indispensable for projecting actual energy costs.
Navigating Complex Energy Efficiency Standards
Globally, building codes are demanding higher levels of energy efficiency. In the United States, ASHRAE Standard 90.1 sets the mandatory minimum efficiency requirements for commercial chillers. Selecting a system that merely meets today’s standard can be a risky long-term strategy. The CogenS™ platform allows you to compare manufacturers and select a high-performance chiller that not only ensures compliance today but also hedges against stricter future regulations.
Beyond Energy: The Total Cost of Ownership (TCO)
A complete lifecycle cost analysis must account for far more than just electricity. CogenS™ models all critical financial inputs, including:
Upfront Capital & Installation Costs (CAPEX)
Annual Energy Consumption
Scheduled Preventive Maintenance Costs
Projected Corrective Repair Costs
Consumables like refrigerants and oils
End-of-life replacement or disposal costs
By simulating these factors over a 20+ year horizon, you can see the true financial impact of your decision.
Start modeling and make the smart, sustainable choice.
Choosing the right chiller can save thousands in energy costs and maintenance — and reduce emissions for years to come. Download CogenS™ – Hydronics MFG Selector for free and gain the ability to model, compare, and select the best-performing chiller solution for your next project.
Understanding Chiller Systems
A chiller is the heart of a commercial or industrial cooling system, responsible for removing heat from a building or process by producing chilled water. This chilled water is distributed through air handlers, fan coils, or process equipment to maintain indoor comfort or support manufacturing operations.
Chiller systems vary in technology, configuration, and efficiency — making the right selection critical for long-term cost and performance.
Key Considerations in Chiller Selection
Energy Efficiency: Often expressed as COP (Coefficient of Performance), EER, or IPLV — the latter reflecting seasonal or part-load performance.
Operating Environment: Ambient temperatures and wet bulb conditions significantly impact performance.
Maintenance and Reliability: Maintenance intervals, startup cycling, and part-load operation affect lifecycle cost.
CogenS™ – Hydronics MFG Selector considers all these inputs using real-world data, allowing engineers and building owners to select the most cost-effective and energy-efficient chiller system for their specific project.
🔬 Powered by Engineering Economics
CogenS™ – Hydronics MFG Selector uses finite horizon total investment analysis, a well-established method for evaluating equipment over a defined project life. It goes beyond initial purchase price to account for:
Energy and fuel costs
Emissions penalties
Maintenance intervals
Performance drift
Inflation and utility price escalation
With CogenS™, every equipment selection becomes a transparent engineering decision — not just a guess.
