Wells to Wheels – The Complete Fuel Life-cycle

Let’s begin with some fact about propane’s environmental performance:

• With respect to on-site greenhouse gas emissions, propane has the lowest emission rate of all major fuel sources, with the exception of natural gas, with which it has comparable performance in many applications.¹
• In terms of life-cycle greenhouse gas emissions, propane produces significantly lower emissions than gasoline, diesel, and electricity on a per-Btu basis.²

What is a Fuel Life-cycle?

When considering the environmental performance of technology, it is important not to overlook the complete life-cycle of the fuel source, as opposed to observing performance at the point-of-use.

A complete fuel life-cycle includes an upstream stage and a downstream stage:

• The upstream stage refers to the sourcing of fuel from its origin (“the well”). This includes all processes for production, transportation and storage until the fuel becomes accessible to end-users.
• The downstream stage is the point-of-use by end-users (“the wheels”).

Why is the Fuel Life-cycle Important?

In order to compare the environmental performance of energy sources, measuring upstream efficiencies and emissions for all production processes should be factored in. For example, when crops are used as biofuels, the formation of nitrous oxide resulting from fertilization is a significant greenhouse emission factor.

The inclusion of upstream performance in energy source comparisons can have an impact on the environmental results of end-use technology.

For example, electricity has zero end-use emissions because the combustion takes place upstream, where the electricity is produced, rather than within the appliance. However, when the life-cycle is considered, a traditional propane water heater emits 60 percent fewer CO2 emissions than its electric counterpart.³

A Comparative Analysis

An insightful analysis comparing the greenhouse gas emissions for propane technology versus a number of other energy sources is available from the U.S. Propane Education and Research Council:

Propane Reduces Greenhouse Gas Emissions: A Comparative Analysis:

• Full Report
• Summary 

For a list of additional reports on the environmental performance of propane in various applications, click here.

Environment Home Page

¹ [Source: PERC, Propane Reduces Greenhouse Gas Emissions: A Comparative Analysis, 2007]
² [Source: PERC, Propane Reduces Greenhouse Gas Emissions: A Comparative Analysis, 2007]
³ [Source: PERC Fact Sheet – Reducing Greenhouse Gas Emissions in the Home, 2007]