ABC Case Study

This tutorial provides a comprehensive case study demonstrating the full capabilities of the Montreal Policy Simulator through a realistic scenario involving multiple substances, applications, and policy interventions.

Contents

Motivation
Starting Conditions
Business as Usual
Policies
Simulations
Complete Implementation
Conclusion

Motivation

In the previous tutorial, we explored the visualization tools available in the Montreal Policy Simulator. This final tutorial demonstrates the full capabilities of the system through a comprehensive case study of ABC, a hypothetical medium-sized nation in the Asia Pacific region.

ABC consumes four substances in manufacturing and servicing: HFC-134a, R-410A, HFC-32, and R-404A. This tutorial specifically builds a simulation from scratch in code, as opposed to earlier tutorials using the UI-based editor. This case study will show how to model complex scenarios involving multiple substances, applications, and policy interventions working together to meet international goals under the Kigali Amendment.

Starting Conditions

Before exploring different potential futures, we start by detailing the current state of ABC by substance. These are based on averages of historic information.

HFC-134a

HFC-134a is used across multiple applications with the following equipment populations and average consumption characteristics (MAC stands for mobile air conditioner):

	Prior Equipment Population (Units)	Initial Charge (kg/unit)	Units Annually Serviced	Annual Retirement	Annual Recharge (kg/unit)
Domestic refrigeration	1,000,000	0.15	10%	5%	0.15
Commercial refrigeration	200,000	0.60	30%	10%	0.60
MAC	500,000	1.00	20%	5%	1.00
Chiller	50,000	5.00	25%	5%	5.00

Local manufacturing for domestic refrigeration is made up of a single manufacturer which accounts for 30,000 units per year are produced. There is no import for domestic refrigeration with HFC-134a. However, 10,000 units per year are imported spread proportionally across all other applications. This has a GWP of 1,430.0 tCO2e.

Code for HFC-134a starting conditions

start default

  define application "Domestic Refrigeration"
  
    uses substance "HFC-134a"
      set priorEquipment to 1000000 units during year beginning
      initial charge with 0.15 kg / unit for sales
      retire 5 % each year
      recharge 10% each year with 0.15 kg / unit
      set manufacture to 30000 units / year during year beginning
      equals 1430 tCO2e / kg
    end substance
  
  end application


  define application "Commercial Refrigeration"
  
    uses substance "HFC-134a"
      set priorEquipment to 200000 units during year beginning
      initial charge with 0.60 kg / unit for sales
      retire 10 % each year  # roughly equivalent to 10 years
      recharge 30% each year with 0.60 kg / unit
      equals 1430 tCO2e / kg
      set import to (10000 * (200000 / 750000)) units / year during year beginning
    end substance
  
  end application


  define application "MAC"
  
    uses substance "HFC-134a"
      set priorEquipment to 500000 units during year beginning
      initial charge with 1.00 kg / unit for sales
      retire 5 % each year
      recharge 20% each year with 1.00 kg / unit
      equals 1430 tCO2e / kg
      set import to (10000 * (500000 / 750000)) units / year during year beginning
    end substance
  
  end application


  define application "Chiller"
  
    uses substance "HFC-134a"
      set priorEquipment to 50000 units during year beginning
      initial charge with 5.00 kg / unit for sales
      retire 5 % each year
      recharge 25% each year with 5.00 kg / unit
      equals 1430 tCO2e / kg
      set import to (10000 * (50000 / 750000)) units / year during year beginning
    end substance
  
  end application

end default

Note: Don't forget that, when setting starting conditions, use during year beginning so that the set command is not repeated across all years.

R-404A Applications

R-404A is used in commercial refrigeration applications:

	Prior Equipment Population (Units)	Initial Charge (kg/unit)	Units Annually Serviced	Annual Retirement	Recharge (kg/unit)
Commercial refrigeration	90,000	10.00	10%	5%	2.00
Transport refrigeration	20,000	2.00	30%	10%	10.00

This substance is fully imported and there is no domestic manufacturing. 1,100 units are being imported currently per year. This has a GWP of 3,921.6 tCO2e. While not currently used in domestic refrigeration, MAC and chiller, this could be a replacement in those applications to HFC-134a with the same annual servicing frequency and retirement but 50% of the initial charge and recharge levels.

Note that when specifying units of equipment in manufacturing (or import) set points, recharge will not reduce the specified amount. For example, setting manufacture to 100 units means 100 new units will be produced on top of the kg that goes into recharge for prior equipment.

Code for R-404A starting conditions

  define application "Transport Refrigeration"

    uses substance "R-404A"
      set priorEquipment to 20000 units during year beginning
      initial charge with 2.00 kg / unit for sales
      retire 5 % each year
      recharge 10% each year with 2.00 kg / unit
      set import to 900 units / year during year beginning
      equals 3921.6 tCO2e / kg
    end substance
  
  end application


  define application "Domestic Refrigeration"

    # ... HFC-134a ...

    uses substance "R-404A"
      initial charge with 0.08 kg / unit for sales
      retire 5 % each year
      recharge 10% each year with 0.08 kg / unit
      equals 3921.6 tCO2e / kg
    end substance

  end application


  define application "Commercial Refrigeration"

    # ... HFC-134a ...
  
    uses substance "R-404A"
      set priorEquipment to 90000 units during year beginning
      initial charge with 10.00 kg / unit for sales
      retire 10 % each year  # roughly equivalent to 10 years
      recharge 30% each year with 10.00 kg / unit
      equals 3921.6 tCO2e / kg
      set import to 200 units / year during year beginning
    end substance
  
  end application


  define application "MAC"

    # ... HFC-134a ...
  
    uses substance "R-404A"
      initial charge with 0.50 kg / unit for sales
      retire 5 % each year
      recharge 20% each year with 0.50 kg / unit
      equals 3921.6 tCO2e / kg
    end substance
  
  end application


  define application "Chiller"

    # ... HFC-134a ...
  
    uses substance "R-404A"
      initial charge with 2.50 kg / unit for sales
      retire 5 % each year
      recharge 25% each year with 2.50 kg / unit
      equals 3921.6 tCO2e / kg
    end substance
  
  end application

HFC-32

HFC-32 is used in domestic and commercial air conditioning:

	Prior Equipment Population (Units)	Initial Charge (kg/unit)	Units Annually Serviced	Annual Retirement	Recharge (kg/unit)
Domestic AC	20,000	0.85	10%	5%	0.85
Commercial AC	5,000	4.00	10%	5%	4.00

There is currently no domestic manufacturing for HFC-32 and 1,000 units are imported per year. This has a GWP of 675.0 tCO2e.

Code for HFC-32 starting conditions

  define application "Domestic AC"

    uses substance "HFC-32"
      set priorEquipment to 20000 units during year beginning
      initial charge with 0.85 kg / unit for sales
      retire 5 % each year  # roughly equivalent to 15 years
      recharge 10% each year with 0.85 kg / unit
      set import to (1000 * (20000 / 25000)) units / year during year beginning
      equals 675.0 tCO2e / kg
    end substance

  end application


  define application "Commercial AC"

    uses substance "HFC-32"
      set priorEquipment to 5000 units during year beginning
      initial charge with 4.00 kg / unit for sales
      retire 5 % each year  # roughly equivalent to 15 years
      recharge 10% each year with 4.00 kg / unit
      set import to (1000 * (5000 / 25000)) units / year during year beginning
      equals 675.0 tCO2e / kg
    end substance

  end application

R-410A

Both substances are used in domestic and commercial air conditioning:

	Prior Equipment Population (Units)	Initial Charge (kg/unit)	Units Annually Serviced	Annual Retirement	Recharge (kg/unit)
Domestic AC	400,000	1.00	10%	5%	1.00
Commercial AC	30,000	5.00	10%	5%	5.00

There is one Domestic AC manufacturer using R-410A with production volume of 40,000 units per annum. Domestic AC are imported at 100 units per year and Commercial AC are imported at 3,000 units per year. This has a GWP of 2,087.5 tCO2e.

Code for R-410A starting conditions

  define application "Domestic AC"

    # ... HFC-32 ...

    uses substance "R-410A"
      set priorEquipment to 400000 units during year beginning
      initial charge with 1.00 kg / unit for sales
      retire 5 % each year  # roughly equivalent to 15 years
      recharge 10% each year with 1.00 kg / unit
      set import to 100 units / year during year beginning
      set manufacture to 40000 units / year during year beginning
      equals 2087.5 tCO2e / kg
    end substance

  end application


  define application "Commercial AC"

    # ... HFC-32 ...

    uses substance "R-410A"
      set priorEquipment to 30000 units during year beginning
      initial charge with 5.00 kg / unit for sales
      retire 5 % each year  # roughly equivalent to 15 years
      recharge 10% each year with 5.00 kg / unit
      set import to 3000 units / year during year beginning
      equals 2087.5 tCO2e / kg
    end substance

  end application

Business as Usual

Before considering policy interventions, we start by examining a business as usual case which does not involve any policy intervention.

General

We first can use national economic growth projections as well as industry growth projections to set overall trends.

Application	2025 - 2030	2031 - 2035	Source
Domestic refrigeration	+ 5% annual growth	+ 3% annual growth	National economic growth
Commercial refrigeration	+ 8% annual growth	+ 5% annual growth	Industry growth in food processing and tourism
Commercial AC	+ 8% annual growth	+ 5% annual growth	Industry growth in food processing and tourism

In addition to these high level trends, there are some assumptions specific to individual substances based on industry surveys. First, we anticipate 50% by weight of HFC initial charge for refrigeration equipment for alternatives. This leads to R-404A initial charges of 0.03 kg / unit for commercial refrigeration and 0.08 for domestic refrigeration.

Code for general business as usual trends

  define application "Domestic Refrigeration"

    uses substance "HFC-134a"
      # ... existing code ...
      change equipment by +5 % each year from year 2025 to 2030
      change equipment by +3 % each year from year 2031 to 2035
    end substance

    # ... R-404A ...

  end application


  define application "Commercial Refrigeration"

    uses substance "HFC-134a"
      # ... existing code ...
      change equipment by +8 % each year from year 2025 to 2030
      change equipment by +5 % each year from year 2031 to 2035
    end substance

    uses substance "R-404A"
      # ... existing code ...
      change equipment by +8 % each year from year 2025 to 2030
      change equipment by +5 % each year from year 2031 to 2035
    end substance

  end application


  define application "Commercial AC"

    uses substance "HFC-32"
      # ... existing code ...
      change equipment by +8 % each year from year 2025 to 2030
      change equipment by +5 % each year from year 2031 to 2035
    end substance

    uses substance "R-410A"
      # ... existing code ...
      change equipment by +8 % each year from year 2025 to 2030
      change equipment by +5 % each year from year 2031 to 2035
    end substance

  end application

That said, we will further refine this based off of additional substance-specific information.

Substance-specific

All that said, let's assume we have some more specific information available about some substances. We will refine our earlier code to reflect.

First, for HFC-32, we expect growth in imports to grow by 100% linearly from 2025 to 2035 without impacting R-410A across all applications. We will assume that this corresponds to an annual average percent increase of 7.18% per the CAGR formula. Also, unlike historic data, the simulation should expect 90% of the R-410A initial charge size. This means 0.90 kg / unit for residential AC and 4.50 kg / unit for commercial AC for imports only.

Code for HFC-32 substance-specific adjustments

  define application "Domestic AC"

    uses substance "HFC-32"
      initial charge with 0.85 kg / unit for sales
      # ... other code ...
      change equipment by +7 % each year from year 2025 to 2035
    end substance

    # ... R-410A ...

  end application


  define application "Commercial AC"

    uses substance "HFC-32"
      initial charge with 4.00 kg / unit for sales
      # ... other code ...
      change equipment by +7 % each year from year 2025 to 2035
    end substance

    # ... R-410A ...

  end application

Next, moving forward, we will assume that HFC consumption will be a bit higher than historic values. Specifically, we will assume a 20% increase over the historic averages in HFC consumption. This should be reflected in starting conditions used in the first year of simulation. This is used to represent HCFC component of baseline.

Code for 20% HFC consumption increase

  define application "Domestic Refrigeration"
  
    uses substance "HFC-134a"
      set priorEquipment to 1000000 * 120 % units during year beginning
      # ... other code ...
    end substance
  
  end application


  define application "Commercial Refrigeration"
  
    uses substance "HFC-134a"
      set priorEquipment to 200000 * 120 % units during year beginning
      # ... other code ...
    end substance
  
  end application


  define application "Mobile AC"
  
    uses substance "HFC-134a"
      set priorEquipment to 500000 * 120 % units during year beginning
      # ... other code ...
    end substance
  
  end application


  define application "Chillers"
  
    uses substance "HFC-134a"
      set priorEquipment to 50000 * 120 % units during year beginning
      # ... other code ...
    end substance
  
  end application


  define application "Domestic AC"

    uses substance "HFC-32"
      set priorEquipment to 20000 * 120 % units during year beginning
      initial charge with 0.85 kg / unit for sales
      retire 5 % each year  # roughly equivalent to 15 years
      recharge 10% each year with 0.85 kg / unit
      set import to 800 units / year during year beginning
      equals 675.0 tCO2e / kg
    end substance

  end application


  define application "Commercial AC"

    uses substance "HFC-32"
      set priorEquipment to 5000 * 120 % units during year beginning
      initial charge with 4.00 kg / unit for sales
      retire 5 % each year  # roughly equivalent to 15 years
      recharge 10% each year with 4.00 kg / unit
      set import to 200 units / year during year beginning
      equals 675.0 tCO2e / kg
    end substance

  end application

Fallback

For variables in application / substance combinations not listed we assume an unchanged continuation of starting of starting conditions based on historic averages. This does not require modification to the code.

Policies

Policy options can be modeled individually or in combination to demonstrate how different intervention strategies would result in compliance or non-compliance with Kigali Amendment targets. Each option addresses different aspects of the HFC consumption cycle. Specifically, we will consider manufacturing prohibition targeting new equipment production, import bans controlling market supply of HFC-based equipment, and enhanced recovery/recycling reducing service sector consumption from existing equipment stock through recharge.

New Equipment Prohibition

Coming into effect in 2028, a full prohibition of domestic manufacturing of new HFC-134a and R-410A equipment. This leads manufacturing consumption of controlled substances to falls but servicing (recharge) continues for existing equipment. In this process, HFC-32 replaces the new units lost that would have otherwise been manufactured by R-410A. However, nothing replaces the new units which are lost from HFC-134a.

Code for manufacturing prohibition policy

start policy "Manufacturing Prohibition"

  modify application "Domestic Refrigeration"
  
    modify substance "HFC-134a"
      cap manufacture to 0 units during years 2028 to onwards
    end substance
  
  end application


  modify application "Domestic AC"

    modify substance "R-410A"
      cap manufacture to 0 units displacing "HFC-32" during years 2028 to onwards
    end substance

  end application


  modify application "Commercial AC"

    modify substance "R-410A"
      cap manufacture to 0 units displacing "HFC-32" during years 2028 to onwards
    end substance

  end application

end policy

Equipment Import Ban

Coming into effect in 2029, this policy would place a full ban on imports for HFC equipment. Instead, imports would shift to alternatives in R-410A and R-404A. These would be based on the application compatibilities of each substance. That said, recharge would continue for existing equipment.

Code for equipment import ban policy

start policy "Equipment Import Ban"

  modify application "Commercial Refrigeration"
  
    modify substance "HFC-134a"
      cap import to 0 units displacing "R-404A" during years 2029 to onwards
    end substance
  
  end application


  modify application "MAC"
  
    modify substance "HFC-134a"
      cap import to 0 units displacing "R-404A" during years 2029 to onwards
    end substance
  
  end application


  modify application "Chiller"
  
    modify substance "HFC-134a"
      cap import to 0 units displacing "R-404A" during years 2029 to onwards
    end substance
  
  end application


  modify application "Domestic AC"

    modify substance "HFC-32"
      cap import to 0 units displacing "R-410A" during years 2029 to onwards
    end substance

  end application


  modify application "Commercial AC"

    modify substance "HFC-32"
      cap import to 0 units displacing "R-410A" during years 2029 to onwards
    end substance

  end application

end policy

Enhanced Recovery and Recycling

Continuous starting in 2026 and increasing to 2029. Over these 4 years, recycling at recharge would go from 14% to 56% with 14% added each year, then drop to 40% from 2030 onwards. By adding code for this, we reduce recharge effectively to 60% of the original value once the policy is in full force. This policy assumes there is no induced demand from the recovered substances displacing sales.

Code for enhanced recovery and recycling policy

start policy "Recovery and Recycling"

  modify application "Domestic Refrigeration"
  
    modify substance "HFC-134a"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance
    
    modify substance "R-404A"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance
  
  end application


  modify application "Commercial Refrigeration"
  
    modify substance "HFC-134a"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance
    
    modify substance "R-404A"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance
  
  end application


  modify application "Mobile AC"
  
    modify substance "HFC-134a"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance
    
    modify substance "R-404A"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance
  
  end application


  modify application "Chillers"
  
    modify substance "HFC-134a"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance
    
    modify substance "R-404A"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance
  
  end application


  modify application "Residential AC"

    modify substance "HFC-32"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance

    modify substance "R-410A"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance

  end application


  modify application "Commercial AC"

    modify substance "HFC-32"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance

    modify substance "R-410A"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance

  end application

end policy

Simulations

Policies can be combined or "stacked" together in different scenarios. We will have the following simulations:

Business as Usual without any policies.
Manufacturing Prohibition with just that intervention alone.
Equipment Import Ban which includes just that policy.
Recovery and Recycling that only includes that program.
Combined which uses all three policies considered at the same time.

Other policy combinations like manufacturing prohibition and equipment import ban may also be added later.

Code for simulation scenarios

start simulations

  simulate "Business as Usual" from years 2025 to 2035

  simulate "Manufacturing Prohibition" using "Manufacturing Prohibition" from years 2025 to 2035

  simulate "Equipment Import Ban" using "Equipment Import Ban" from years 2025 to 2035

  simulate "Recovery and Recycling" using "Recovery and Recycling" from years 2025 to 2035

  simulate "Combined" 
    using "Manufacturing Prohibition" 
    then "Equipment Import Ban" 
    then "Recovery and Recycling" 
  from years 2025 to 2035

end simulations

Complete Implementation

The full implementation combines all the elements we've discussed above into a single comprehensive model. This demonstrates how complex policy scenarios can be constructed by building up from basic starting conditions through business as usual projections to sophisticated policy interventions.

Code for complete ABC case study implementation

start default

  define application "Domestic Refrigeration"

    uses substance "HFC-134a"
      set priorEquipment to 1000000 units during year beginning
      initial charge with 0.15 kg / unit for sales
      retire 5 % each year
      recharge 10 % each year with 0.15 kg / unit
      set manufacture to 30000 units / year during year beginning
      change equipment by +5 % each year during years 2026 to 2030
      change equipment by +3 % each year during years 2031 to 2035
      equals 1430 tCO2e / kg
    end substance

    uses substance "R-404A"
      initial charge with 0.08 kg / unit for sales
      retire 5 % each year
      recharge 10 % each year with 0.08 kg / unit
      equals 3921.6 tCO2e / kg
    end substance

  end application

  define application "Commercial Refrigeration"

    uses substance "HFC-134a"
      set priorEquipment to 200000 units during year beginning
      initial charge with 0.60 kg / unit for sales
      retire 10 % each year  # roughly equivalent to 10 years
      recharge 30 % each year with 0.60 kg / unit
      set import to (10000 * (200000 / 750000)) units / year during year beginning
      change equipment by +8 % each year during years 2026 to 2030
      change equipment by +5 % each year during years 2031 to 2035
      equals 1430 tCO2e / kg
    end substance

    uses substance "R-404A"
      set priorEquipment to 90000 units during year beginning
      initial charge with 10.00 kg / unit for sales
      retire 10 % each year  # roughly equivalent to 10 years
      recharge 30 % each year with 10.00 kg / unit
      set import to 200 units / year during year beginning
      change equipment by +8 % each year during years 2026 to 2030
      change equipment by +5 % each year during years 2031 to 2035
      equals 3921.6 tCO2e / kg
    end substance

  end application

  define application "MAC"

    uses substance "HFC-134a"
      set priorEquipment to 500000 units during year beginning
      initial charge with 1.00 kg / unit for sales
      retire 5 % each year
      recharge 20 % each year with 1.00 kg / unit
      set import to (10000 * (500000 / 750000)) units / year during year beginning
      equals 1430 tCO2e / kg
    end substance

    uses substance "R-404A"
      initial charge with 0.50 kg / unit for sales
      retire 5 % each year
      recharge 20 % each year with 0.50 kg / unit
      equals 3921.6 tCO2e / kg
    end substance

  end application

  define application "Chiller"
    # Chillers are large size ACs that other simulations may put under the commercial AC 
    # category but it should be its own application category for the case study

    uses substance "HFC-134a"
      set priorEquipment to 50000 units during year beginning
      initial charge with 5.00 kg / unit for sales
      retire 5 % each year
      recharge 25 % each year with 5.00 kg / unit
      set import to (10000 * (50000 / 750000)) units / year during year beginning
      equals 1430 tCO2e / kg
    end substance

    uses substance "R-404A"
      initial charge with 2.50 kg / unit for sales
      retire 5 % each year
      recharge 25 % each year with 2.50 kg / unit
      equals 3921.6 tCO2e / kg
    end substance

  end application

  define application "Transport Refrigeration"

    uses substance "R-404A"
      set priorEquipment to 20000 units during year beginning
      initial charge with 2.00 kg / unit for sales
      retire 5 % each year
      recharge 10 % each year with 2.00 kg / unit
      set import to 900 units / year during year beginning
      equals 3921.6 tCO2e / kg
    end substance

  end application

  define application "Domestic AC"

    uses substance "HFC-32"
      set priorEquipment to 20000 units during year beginning
      initial charge with 0.85 kg / unit for sales
      retire 5 % each year  # roughly equivalent to 15 years
      recharge 10 % each year with 0.85 kg / unit
      set import to (1000 * (20000 / 25000)) units / year during year beginning
      change equipment by +7 % each year during years 2026 to 2035
      equals 675 tCO2e / kg
    end substance

    uses substance "R-410A"
      set priorEquipment to 400000 units during year beginning
      initial charge with 1.00 kg / unit for sales
      retire 5 % each year  # roughly equivalent to 15 years
      recharge 10 % each year with 1.00 kg / unit
      set import to 100 units / year during year beginning
      set manufacture to 40000 units / year during year beginning  # recharge will not reduce 
      # when units are specified in a set point - setting manufacture to 100 units means 100 
      # new units will be produced on top of the kg that goes into recharge for prior equipment
      equals 2087.5 tCO2e / kg
    end substance

  end application

  define application "Commercial AC"

    uses substance "HFC-32"
      set priorEquipment to 5000 units during year beginning
      initial charge with 4.00 kg / unit for sales
      retire 5 % each year  # roughly equivalent to 15 years
      recharge 10 % each year with 4.00 kg / unit
      set import to (1000 * (5000 / 25000)) units / year during year beginning
      change equipment by +7 % each year during years 2026 to 2035
      equals 675 tCO2e / kg
    end substance

    uses substance "R-410A"
      set priorEquipment to 30000 units during year beginning
      initial charge with 5.00 kg / unit for sales
      retire 5 % each year  # roughly equivalent to 15 years
      recharge 10 % each year with 5.00 kg / unit
      set import to 3000 units / year during year beginning
      change equipment by +8 % each year during years 2026 to 2030
      change equipment by +5 % each year during years 2031 to 2035
      equals 2087.5 tCO2e / kg
    end substance

  end application

end default


start policy "Manufacturing Prohibition"

  modify application "Domestic Refrigeration"
    modify substance "HFC-134a"
      cap manufacture to 0 units during years 2028 to onwards
    end substance
  end application

  modify application "Domestic AC"
    modify substance "R-410A"
      cap manufacture to 0 units displacing "HFC-32" during years 2028 to onwards
    end substance
  end application

  modify application "Commercial AC"
    modify substance "R-410A"
      cap manufacture to 0 units displacing "HFC-32" during years 2028 to onwards
    end substance
  end application

end policy


start policy "Equipment Import Ban"

  modify application "Commercial Refrigeration"
    modify substance "HFC-134a"
      cap import to 0 units displacing "R-404A" during years 2029 to onwards
    end substance
  end application

  modify application "MAC"
    modify substance "HFC-134a"
      cap import to 0 units displacing "R-404A" during years 2029 to onwards
    end substance
  end application

  modify application "Chiller"
    modify substance "HFC-134a"
      cap import to 0 units displacing "R-404A" during years 2029 to onwards
    end substance
  end application

  modify application "Domestic AC"
    modify substance "HFC-32"
      cap import to 0 units displacing "R-410A" during years 2029 to onwards
    end substance
  end application

  modify application "Commercial AC"
    modify substance "HFC-32"
      cap import to 0 units displacing "R-410A" during years 2029 to onwards
    end substance
  end application

end policy


start policy "Recovery and Recycling"

  modify application "Domestic Refrigeration"
    modify substance "HFC-134a"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance
    modify substance "R-404A"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance
  end application

  modify application "Commercial Refrigeration"
    modify substance "HFC-134a"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance
    modify substance "R-404A"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance
  end application

  modify application "MAC"
    modify substance "HFC-134a"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance
    modify substance "R-404A"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance
  end application

  modify application "Chiller"
    modify substance "HFC-134a"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance
    modify substance "R-404A"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance
  end application

  modify application "Domestic AC"
    modify substance "HFC-32"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance
    modify substance "R-410A"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance
  end application

  modify application "Commercial AC"
    modify substance "HFC-32"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance
    modify substance "R-410A"
      recover 14 % with 100 % reuse displacing sales during year 2026
      recover 28 % with 100 % reuse displacing sales during year 2027
      recover 42 % with 100 % reuse displacing sales during year 2028
      recover 56 % with 100 % reuse displacing sales during year 2029
      recover 40 % with 100 % reuse displacing sales during years 2030 to onwards
    end substance
  end application

end policy


start simulations

  simulate "Business as Usual" from years 2025 to 2035

  simulate "Manufacturing Prohibition" using "Manufacturing Prohibition" from years 2025 to 2035

  simulate "Equipment Import Ban" using "Equipment Import Ban" from years 2025 to 2035

  simulate "Recovery and Recycling" using "Recovery and Recycling" from years 2025 to 2035

  simulate "Combined Policies" 
    using "Manufacturing Prohibition" 
    then "Equipment Import Ban" 
    then "Recovery and Recycling" 
  from years 2025 to 2035

end simulations

You can also download the complete case study implementation as a QTA file to use in the editor. There are two options:

case_study.qta - This is what we built up here together and is recommended for code-based exploration.
case_study_subdivided.qta - This is the same logic but further broken down, recommended for UI-based exploration with more granular policy options.

To use these files, open the editor and click "Load File" at the top of the page. Then, select the downloaded QTA file.

Conclusion

This comprehensive case study demonstrates the full capabilities of Kigali Sim in modeling complex, realistic scenarios. We have explored how to construct sophisticated models that include:

Multiple substances across different applications
Realistic business-as-usual growth projections based on economic data
Targeted policy interventions including manufacturing bans, import restrictions, and recycling programs
Complex scenario analysis combining multiple policies

The ABC case study shows how the simulator can support policy makers in evaluating different pathways to meet international goals under agreements like the Kigali Amendment. By modeling various combinations of policies, decision makers can understand the trade-offs and compounding effects between different intervention strategies.

This marks the end of our tutorial series. You now have the knowledge and tools to create sophisticated simulations that can inform policy decisions and help address global environmental challenges. We encourage you to experiment with your own scenarios and explore the full potential of this powerful modeling platform.