Wells to Wheels – The Complete Fuel Life-Cycle

“Wells to wheels” is a phrase that environmental and energy experts used to describe a complete life cycle of a fuel, from the time it is extracted or created (i.e. pumped from the well), to the time it is used (i.e. fuelling an engine to turn the wheels).

It’s an important concept, since the best way to compare the environmental performance of a fuel is to look at all of its impacts, from beginning to end. This includes the ‘upstream’ stages, where the fuel is produced, transported and stored, and the ‘downstream’ stage where it is actually used as fuel.

Taking this big picture approach creates a true, and sometimes surprising, estimate of environmental costs. For example, electricity has no emissions in the downstream stage, where it used by consumers or businesses, but it still has a significant environmental cost in the upstream stage, where it is produced and transmitted. As a result, a traditional propane water heater emits 60 percent fewer CO2 emissions than its electric counterpart3 on a wells to wheels basis.

Bio-fuels are another noteworthy example. If you didn’t know that fertilizing the crops used in bio-fuels creates nitrous oxide, a significant greenhouse gas, you might not see the full picture.

How Does Propane Compare?

On the full wells to wheels basis, propane has the lowest greenhouse gas emission rate of all major fuel sources (natural gas is competitive, but it is a greenhouse gas itself).¹ When you look at how many emissions are created for every unit of energy produced, propane ranks significantly better than gasoline, diesel or electricity.²

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