BACKGROUND ON MATERIALS GREENHOUSE GAS EMISSIONS

John DavisHigh Desert RMDZApril 10, 2014

300,000 feet view

Intergovernmental Panel on Climate Change

http://www.esrl.noaa.gov/

Greenhouse Gases and Global Warming Potentials

Important GHG Terms

Anthropogenic Emissions:Man-made emissions (e.g., fossil fuels combustion)Add new CO2 (and other GHGs) to atmosphere; not part of

natural carbon cycle

Biogenic Emissions:CO2 emissions only Part of natural closed loop carbon cycleNot considered new emissions to atmosphere

Lifecycle Assessment: Principles and Practice USEPA, 2006

GHG Emission Sources And Sinks

Disposal

Reco

very

WASTE management vs. MATERIALS management

Product Lifecycle http://www.epa.gov/smm/vision.htm

Disposal

Reco

very

WASTE management vs. MATERIALS management

Product Lifecycle http://www.epa.gov/smm/vision.htm

Recycle

Recycling rate impact1 ton

bottles1 ton paper1 ton food1 ton wood1 ton cans1 ton carpet1 ton grass

= 1 ton diverted

Greenhouse Gas emission impact

= ? mmt CO2e

1 ton bottles1 ton paper1 ton food1 ton wood1 ton cans1 ton carpet1 ton grass

Waste Reduction Model (WARM)• WARM can quantify and communicate GHG Benefits

• Metric tons of Carbon Equivalent (MTCE)• Metric Tons of Carbon Dioxide Equivalent • (MTCO2E)• Energy benefits – British Thermal Units (BTU)

www.epa.gov/warm

WARM Background• The primary application of WARM is to support

materials-related decision-making in the context of climate change.

• WARM compares the emissions and offsets resulting from a material in a baseline and an alternative management pathway in order to provide decision-makers with comparative emission results.

• WARM does not include emissions from the use phase of a product’s life, since use does not have an effect on the waste management emissions of a product.

WARM Formula• The general formula for net GHG emissions for each scenario

modeled in WARM:

Net GHG emissions = Gross manufacturing GHG emissions - (Increase in carbon stocks + Avoided utility GHG emissions)

Materials Management Decisions Affecting GHG Reduction:

• Energy consumption (specifically combustion of fossil fuels) and the resulting GHG emissions associated with material extraction, manufacturing, transporting, and end-of-life management of the material or product .

• Non-energy-related manufacturing emissions, such as the carbon dioxide (CO2) released when limestone used in steel manufacturing is converted to lime, or the perfluorocarbons (PFCs) generated during the aluminum smelting process.

Materials Management Decisions Affecting GHG Reduction:

• Methane (CH4) emissions from decomposition of organic materials in landfills.

• CO2 and nitrous oxide (N2O) emissions from waste combustion.

• Carbon sequestration and storage, which refer to natural or manmade processes that remove carbon from the atmosphere and store it for long periods or permanently.

Streamlined Life Cycle Methodology

• Begins at a “waste generation” reference point• Focus on GHGs emitted, carbon stored, or utility energy

displaced at following stages:• Raw material acquisition (upstream)• Manufacturing (upstream) • Waste management (downstream) • Transportation of raw material and waste

Emission Factors Developed for:

• Source reduction• Recycling• Composting• Combustion• Landfilling • 26 material types and 6 categories of mixed materials

(paper, metals, plastics, organics, MSW, and recyclables)

http://epa.gov/epawaste/conserve/tools/warm/SWMGHGreport.html

• Documentation explains the calculation of emission factors by material type, or group of materials, arranged into individual chapters

• Chapter-based, material-focused formats provide detailed and up-to-date information about the WARM emission factors

• Several Background Documents are available that provide additional useful information pertaining to the WARM emission factors

Documentation for WARM Greenhouse Gas Emission and Energy Factors

• Asphalt Concrete• Asphalt Shingles• Carpet• Clay Bricks• Concrete• Drywall• Fiberglass Insulation• Fly Ash• Glass• Metals• Organics• Paper Products• Personal Computers• Polylactide (PLA) Biopolymers• Plastics• Tires• Vinyl Flooring• Wood Flooring• Wood Products

Lifecycle of Carpet in WARM

Detailed Recycling Flows for Carpet in WARM