A Citizen’s Guide

SUPER-CRITICAL: The natural gas pipeline can be a dense topic, in more ways than one.

In testimony before the Legislature this week, a BP executive spoke about how the natural gas in the proposed pipeline would be shipped in a “dense” phase. This proposal may have important implications for Alaska.

Dave Van Tuyl of BP said the dense phase means that the natural gas and natural gas liquids mixture in the pipeline “isn’t really liquid and it isn’t really gas, it’s super-critical,” according to a summary by legislative consultant Rick Harper.

In a memo to Sen. Gene Therriault, Harper wrote that he has heard of this condition referred to in the past as a “plasma-type state.”

He said that during his 34 years working in the industry, “I have not witnessed any situation where natural gas was transported in this condition in North America.”

“I believe this is a significant feature in the prospective design of the gasline that is proposed in the contract,” said Harper, whose experience includes 15 years with ARCO and a stint as president of ARCO Gas.

The dense phase is achieved by operating the pipeline under greater pressure, which makes it more efficient at transporting BTUs.

Harper said he is not sure of the implications of the “plasma” plan, but one possibility is that “the ability to process and remove natural gas liquids upstream of the pipeline terminus in Alberta (or the Midwest) might be restricted economically or physically.”

Natural gas includes both methane, a light gas, and heavier components that include ethane, propane, and butane, fuels that are more valuable when they are separated from the natural gas stream. These fuels are referred to as “natural gas liquids.” They are often used as petrochemical feedstocks, for example.

There has been discussion many times over the past three decades of gas pipeline plans about the potential of removing some natural gas liquids in Alaska as a way to spur industry.

Harper said that another aspect for review is to see how the “dense” transmission plan might impact assumptions about how economical it may be in the future to expand the pipeline and promote more production from new sources.

This seems to me to be another in the long line of issues related to the gas pipeline that deserve a closer examination.

The state needs to work with the oil companies to see if the design plan means that removing some of the liquids in Alaska would be possible or impossible.

Our lawmakers should resist the pressure to act on this deal before the special session ends next week. There are just too many loose ends and unanswered questions.

If these issues are not dealt with in advance, it will be difficult or perhaps impossible to negotiate changes in the future because of the nature of the deal.

It’s super-critical that the research and analysis take place before a contract is completed.