We think natural gas will come in over the next several decades from a variety of sources in Canada. We have conventional gas resources. We have what's known as tight gas or coal bed methane, for example, in the border between Alberta and British Columbia in what's called the Montney area. Then we have shale gas as well. There is also a tremendous resource in Canada of renewable natural gas, called biogas in many cases, and that's gas that comes from waste material like landfills, dairy farms, and other renewable sources. So there's a whole range of sources of natural gas for transportation. It's not any one source, such as shale gas. It's going to come from a whole range of sources.
We already have facilities in Canada that are generating biogas, which comes from waste sources such as a waste water treatment plant, for the purpose of re-injecting it into the pipeline grid and selling it to consumers.
In the United States we actually have dairy farms that are collecting the methane from sources you can imagine and then they are trapping it, they're cleaning it a small amount, and they're fueling their vehicles with that methane. So it's a virtuous life cycle.
Waste Management operates a fleet just outside of San Francisco where they take garbage up to a landfill. The landfill then produces methane. They collect all that methane, they clean it, and they fuel all their garbage trucks. There's no fossil-based natural gas used in that life stream.
So there is a whole variety of alternatives. It's been done in Scandinavia for over a decade, where biogas is being extracted from a whole number of waste streams. There's already very proven commercial technology around deriving biogas, or renewable natural gas, from things like farm waste, forestry residue, other waste materials, organic waste.