Tutorial 12: Equipment Energy Efficiency Comparison

Motivation

In the previous tutorial, we explored GWP but equipment energy efficiency also plays a crucial role in environmental impact. Energy-efficient equipment consumes less electricity, reducing both operational costs and indirect emissions from power generation. In this tutorial, we'll model an energy efficiency policy that gradually replaces high-energy equipment with low-energy alternatives. To narrow our focus to these effects, we'll examine how this transition can significantly reduce overall energy consumption (measured in kWh) while maintaining the same refrigerant type and cooling capacity. However, in practice, you can model both changes in substance and changes in equipment simultaneously.

Setting Up the Business-as-Usual Scenario

Note: In these feature specific tutorials, we will start from scratch each time. Click Save File to save your current work and then click New File to start a simulation.

Let's create our baseline scenario with both high-energy and low-energy models of the same HFC-134a refrigeration equipment. We'll start with high-energy models dominating the market and minimal low-energy model adoption.

Step 1: Create the Domestic Refrigeration application

• Click Add Application.
• Name it "Domestic Refrigeration" without quotes.
• Click Finish.

Step 2: Add HFC-134a High Energy equipment model

• Click Add Consumption.
• On the General tab:
  • Name it "HFC-134a" and use "Domestic Refrigeration" without quotes.
  • Select Domestic Refrigeration as the Application.
  • Set GWP to 1430 kgCO2e/kg.
  • Set annual energy consumption to 500 kwh/unit, referring to annual amortized consumption.
  • Enable domestic manufacture.
• On the Equipment tab:
  • Set equipment type as "high energy" without quotes.
  • Set initial charge to 0.15 kg/unit for domestic manufacture.
  • Set annual retirement to 5% each year.
• On the Servicing tab:
  • Set recharge to 10% with 0.15 kg/unit during all years.
• On the Set tab:
  • Set prior equipment to 1,000,000.0 units in year 2025.
  • Set domestic manufacture to 20 mt in year 2025.
• Click Finish

Step 3: Add HFC-134a Low Energy equipment model

• Click Add Consumption
• On the General tab:
  • Name it "HFC-134a" and use "Domestic Refrigeration" without quotes.
  • Set GWP to 1430 kgCO2e/kg.
  • Set annual energy consumption to 350 kwh/unit, referring to annual amortized consumption.
  • Enable domestic manufacture.
• On the Equipment tab:
  • Set equipment type as "low energy" without quotes.
  • Set initial charge to 0.15 kg/unit for domestic manufacture.
  • Set annual retirement to 5% each year.
• On the Servicing tab:
  • Set recharge to 10% with 0.15 kg/unit during all years.
• On the Set tab:
  • Set prior equipment to 1,000.0 units in year 2025.
  • Set domestic manufacture to 10 mt in year 2025.
• Click Finish

Step 4: Create baseline simulation

• Click Add Simulation.
• Name it "BAU" without quotes.
• Set duration from years 2025 to 2035.
• Click Finish.

You should now see your baseline simulation running. We expect that the high-energy model is the dominant equipment with much higher consumption volumes than the low-energy alternative. To see this, select the Population and Equipment radio buttons (make sure All is selected in the equipment panel). With the specifics of the values we entered in given the production numbers and recharge demands, there is very slight decrease in high energy equipment over time and a gradual increase in low energy. However, overall population is increasing.

Adding the Energy Efficiency Policy

Now let's create a policy that accelerates this replacement of high-energy equipment consumption with low-energy models. This will demonstrate how an equipment efficiency policy can reduce overall energy consumption without changing refrigerant type.

Step 1: Create the efficiency policy

• Click Add Policy.
• Name it "Energy Efficiency" without quotes.
• Select Domestic Refrigeration as the application.
• Select HFC-134a - high energy as the substance.

Step 2: Configure the replacement mechanism

• Go to the Replace tab within your HFC-134a High Energy policy configuration.
• Click Add Replacement.
• Set to replace 20% of all sales.
• Indiciate that it is to be replaced with HFC-134a - low energy
• Set timing to starting in 2028 to onwards
• Click Finish to finish the policy

This policy will progressively reduce high-energy equipment consumption relative to the BAU. Specifically, we change 20% of high energy sales each year starting in 2028 with that demand being met by low-energy equipment instead. This accelerates that change we saw earlier. However, before we can see the effects, we need to make an additional simulation.

Creating the Simulation

Next, let's create a simulation to compare the policy scenario with our business-as-usual baseline.

• Click Add Simulation.
• Name it "Efficiency Policy" without quotes.
• Check the Energy Efficiency policy checkbox
• Set duration from years 2025 to 2035
• Click Finish

Kigali Sim is now simulating both options but we need to configure the visualizations to do a comparison.

Results

Let's examine how the efficiency policy affects both equipment adoption and energy consumption:

Equipment Comparison

• Select the Population radio button
• Ensure total and million units is selected
• Select Simulations radio
• Select All under the simulations list

Compare the BAU and Efficiency Policy simulations and notice how overall number of units of equipment remains effectively the same. Next, let's consider the energy consumption.

Energy Comparison

• Keep Population selected with total
• Select GWh / year instead of units of equipment
• Ensure Simulations is selected with All to compare the two scenarios
• To better see the results, change Absolute Value to Relative to BAU

Taken together, even though total equipment population and refrigerant consumption stay roughly constant, the overall kWh consumption drops substantially. This is because we're replacing equipment that consumes 500 kWh/year with units that consume only 350 kWh/year, a 30% efficiency improvement.

Conclusion

You've successfully modeled an equipment energy efficiency policy! This tutorial demonstrated:

• Equipment differentiation: How the same refrigerant can have different environmental impacts based on equipment efficiency
• Energy-focused policies: Using "replace X% of sales with substance" to model efficiency transitions
• Indirect impact reduction: How energy efficiency reduces environmental impact beyond direct refrigerant emissions
• Market transformation: Modeling progressive adoption of efficient technologies relative to BAU

Note: Kigali Sim only models energy consumption and direct emissions from covered substances. However, you can use the Export Spreadsheet button to model with the country's energy mix to further explore impacts.

Download the completed tutorial: tutorial_12.qta - this contains the complete energy efficiency comparison model with equipment transition policy

Next Steps

You've now completed both Feature-Specific tutorials! You've learned how to model GWP-focused refrigerant substitution (Tutorial 11) and energy efficiency equipment transitions (Tutorial 12). These tutorials complement each other to provide a comprehensive understanding of environmental impact assessment in cooling systems.

Previous: Tutorial 11 | Next: Tutorial 13 | Guide Index