Challenges in Analyzing a Cap on Consumption of F-GHGs Deborah Ottinger and David S. Godwin USEPA NCGG-5

Overview Background on fluorinated GHGs –Practicality of upstream control of deliberately produced F-GHGs Analyzing consumption patterns and controls –Differences between emissions and consumption Long-lived, pressurized equipment Electronics manufacturing –Differences between emissions marginal abatement cost curves (MACs) and consumption MACs

3 How Are F-GHGs Emitted? Fluorinated Gases Emitted during use Magnesium Production and Casting Other Uses Nonessential Uses Primary Aluminum Production Manufacturing HCFC-22 (ODS) Produced as Byproduct Magnesium Production & Casting Electronics Manufacturing Electric T & D Equipment Emitted During Use Other Industrial Sources Refrigeration & Air Conditioning Foam-Blowing Agents Fire Suppression Cleaning Solvents Aerosols Metered-Dose Inhalers Emitted During Use & Disposal Substitutes for Ozone-Depleting Substances High GWP Gases Fumigants

4 U.S. GHG Emissions (2006)

5 U.S. F-GHG Emissions from Consuming Uses (2006) Total = 132 MtCO 2 e

Upstream Control Hundreds of millions of emission points –HFCs in motor vehicle and household and commercial A/C, refrigeration –SF 6 in electrical equipment along thousands of miles of transmission lines producers, hundreds of importers, exporters Upstream control –Is easier to implement –Has much greater coverage –Has precedent under Montreal Protocol

Analytical Challenges Most projections, MACs to date are expressed in terms of emissions. Cannot be directly applied to consumption –Consumption significantly higher than emissions –Impact of reduction options on consumption often different from that on emissions –Relationship between consumption and emissions varies by end use, mitigation option, and over time. Same dynamics complicate attempts to project future consumption from current consumption.

Consumption Larger Than Emissions Foams and long-lived equipment are growing and store HFCs and SF 6 for long periods Electronics manufacturing partially destroys F- GHGs (mainly PFCs) in process of using them. U.S. Potential and Actual Emissions of F-GHGs (2006)

Dynamics: Long-lived Equipment Consumption driven by –Net increase in total nameplate capacity of the equipment (new NC – retiring NC) –Replacement of emitted F-GHG Relationship between these two drivers dictates relationship between F-GHG consumption and emissions.

Difference Largest for Newly Introduced F-GHG No retiring equipment from which to recover gas to help charge/recharge equipment. Bank and therefore emissions relatively small. Difference declines as F-GHG penetrates stock of equipment.

Simple Model Following slides show results from a simple model based on a hypothetical equipment set. Model allows user to explore relationship between consumption and emissions for long-lived, pressurized equipment. User selects values for equipment lifetime, recharge frequency, growth rate, leak rate, fraction gas recovered on “Model” tab. Results shown on “Potential Approach” and “Potential Approach Ratio” tabs. Double-click icon to open.

Consumption and Emissions for Equipment with No Long-Term Growth, a 20-year lifetime, and 100% Recovery of Gas at Disposal

Ratio of Emissions to Consumption for Equipment with No Long-Term Growth, a 20-year lifetime, and 100% Recovery of Gas at Disposal

Consumption and Emissions for Equipment with No Long-Term Growth, a 20-year lifetime, and No Recovery of Gas at Disposal

Ratio of Emissions to Consumption for Equipment with No Long- Term Growth, a 20-year lifetime, and No Recovery of Gas at Disposal

Consumption and Emissions for Equipment with 3% Long-Term Growth, 3% Emission Rate

Ratio of Emissions to Consumption for Equipment with 3% Long- Term Growth, 3% Emission Rate

Steady-state relationship between emissions and consumption (reached once equipment begins to retire) Where: R = the years between recharges of equipment g = the annual growth rate of new equipment (the same as the long-term growth rate of the equipment stock after the F-GHG has been used in the equipment for its lifetime) Leak Rate = the leak rate during equipment operation

Emissions/Consumption as a Function of Long-Term Growth and Emissions Rates

Vintaging Model US HFC Consumption and Emissions

Projecting Consumption by Long-Lived Equipment Based on Past Consumption Chemical transition increases TOTAL demand for chemical because gas from retiring equipment can’t be used to charge new. –Effect small if little gas is currently recovered from retiring equipment –Otherwise, projections based on 2005 HFCs HCFCs could underestimate future demand

Increase in Consumption Due to Chemical Transition in Year 19 (100% recovery at disposal)

No Increase in Consumption Due to Chemical Transition If No Recovery at Disposal

Dynamics: Electronics Manufacturing Etching and cleaning processes deliberately dissociate F-GHGs to generate a plasma of fluorine atoms. Abatement equipment sometimes used to destroy residual F-GHGs emerging from process. Destruction rates vary widely depending on F- GHG, process, design and operation of abatement equipment.

Differences Between Emissions and Consumption MACs Options reducing use of fluorinated GHG in foams or equipment have larger effect on consumption than emissions. Options destroying the F-GHG after use have larger effect on emissions than consumption. Costs ($/tCO2e) differ, sometimes changing order in which options are implemented. In general reductions are larger and more immediate in consumption MACs. Difference between MACs (in terms of tCO2e reduced) declines as mitigation options penetrate stock of equipment.

Impact of Options on Consumption vs. Emissions Greater impact on consumption –Replacement with lower/zero-GWP chemical in foams, equipment –Charge reduction (e.g., secondary loops) Same impact –Replacement with lower/zero-GWP chemical in immediately emissive uses (e.g., Mg production) –Recovery and recycling in equipment Smaller impact on consumption –F-GHG destruction following use (foams, electronics) –Leak detection and repair (if recharges infrequent)

Consumption and Emissions Reductions for Equipment with 3% Long-Term Growth, 3% Emission Rate: F-GHG Replacement

Ratio of Emissions to Consumption Reductions for Equipment with 3% Long-Term Growth, 3% Emission Rate

Consumption and Emissions Reductions for Equipment with 3% Long-Term Growth, 5-Year Recharge Period: Leak Repair

2015 U.S. Consumption and Emission MACs for ODS Substitutes

2020 U.S. Consumption and Emission MACs for ODS Substitutes

2025 U.S. Consumption and Emission MACs for ODS Substitutes

Acknowledgements Our thanks to Marian Van Pelt and her staff at ICF for their work maintaining the Vintaging Model and developing the emissions and consumption projections and MACs based on it.

Contact Information Deborah Ottinger: David Godwin: