GREET Model

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GREET (Greenhouse gases, Regulated Emissions, and Energy use in Technologies) is a full life-cycle model sponsored by the Argonne National Laboratory (U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy). It fully evaluates energy and emission impacts of advanced and new transportation fuels, the fuel cycle from well to wheel and the vehicle cycle through material recovery and vehicle disposal. It allows researchers and analysts to evaluate various vehicle and fuel combinations on a full fuel-cycle/vehicle-cycle basis.

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The GREET model is specified in the Inflation Reduction Act of 2022 §45V as the methodology to calculate the lifecycle greenhouse gas emissions "through the point of production (well-to-gate)" when determining the level of tax credit for clean Hydrogen production until a successor is approved by the Secretary of the Treasury.

The basic implementation of the model was made using Excel spreadsheets. However a more practical and easy to use software developed with .NET and with a fully graphical toolbox is also available.

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For a given vehicle and fuel system, GREET separately calculates the following:

GREET includes more than 100 fuel production pathways and more than 70 vehicle/fuel systems.

Michael Wang, a Senior Scientist in the Energy Systems Division is the primary developer of GREET.

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<span class="mw-page-title-main">Alternative fuel</span> Fuels from sources other than fossil fuels

Alternative fuels, also known as non-conventional and advanced fuels, are fuels derived from sources other than petroleum. Alternative fuels include gaseous fossil fuels like propane, natural gas, methane, and ammonia; biofuels like biodiesel, bioalcohol, and refuse-derived fuel; and other renewable fuels like hydrogen and electricity.

<span class="mw-page-title-main">Zero-emissions vehicle</span> Class of motor vehicle

A zero-emission vehicle, or ZEV, is a vehicle that does not emit exhaust gas or other pollutants from the onboard source of power. The California definition also adds that this includes under any and all possible operational modes and conditions. This is because under cold-start conditions for example, internal combustion engines tend to produce the maximum amount of pollutants. In a number of countries and states, transport is cited as the main source of greenhouse gases (GHG) and other pollutants. The desire to reduce this is thus politically strong.

<span class="mw-page-title-main">Fossil fuel power station</span> Facility that burns fossil fuels to produce electricity

A fossil fuel power station is a thermal power station which burns a fossil fuel, such as coal or natural gas, to produce electricity. Fossil fuel power stations have machinery to convert the heat energy of combustion into mechanical energy, which then operates an electrical generator. The prime mover may be a steam turbine, a gas turbine or, in small plants, a reciprocating gas engine. All plants use the energy extracted from the expansion of a hot gas, either steam or combustion gases. Although different energy conversion methods exist, all thermal power station conversion methods have their efficiency limited by the Carnot efficiency and therefore produce waste heat.

<span class="mw-page-title-main">National Energy Technology Laboratory</span> United States research lab

The National Energy Technology Laboratory (NETL) is a U.S. national laboratory under the Department of Energy Office of Fossil Energy. NETL focuses on applied research for the clean production and use of domestic energy resources. It performs research and development on the supply, efficiency, and environmental constraints of producing and using fossil energy resources while maintaining affordability.

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<span class="mw-page-title-main">Flue gas</span> Gas exiting to the atmosphere via a flue

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<span class="mw-page-title-main">Greenhouse gas emissions</span> Sources and amounts of greenhouse gases emitted to the atmosphere from human activities

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<span class="mw-page-title-main">Greenhouse gas emissions by the United States</span> Climate changing gases from the North American country

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<span class="mw-page-title-main">Fossil fuel phase-out</span> Gradual reduction of the use and production of fossil fuels

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<span class="mw-page-title-main">Greenhouse gas emissions by China</span> Emissions of gases harmful to the climate from China

China's greenhouse gas emissions are the largest of any country in the world both in production and consumption terms, and stem mainly from coal burning, including coal power, coal mining, and blast furnaces producing iron and steel. When measuring production-based emissions, China emitted over 14 gigatonnes (Gt) CO2eq of greenhouse gases in 2019, 27% of the world total. When measuring in consumption-based terms, which adds emissions associated with imported goods and extracts those associated with exported goods, China accounts for 13 gigatonnes (Gt) or 25% of global emissions.

Michael Wang is a distinguished fellow, a senior scientist, and director of the Systems Assessment Center of the Energy Systems Division at the U.S. Department of Energy’s (DOE) Argonne National Laboratory. He is also a faculty associate in the Energy Policy Institute at The University of Chicago; a senior fellow at the Northwestern-Argonne Institute of Science and Engineering at Northwestern University.

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