Encana boosting liquefied natural gas for fleet fueling

Encana will distribute LNG via both mobile and permanent public fueling stations. LNG is easily transported and stored. It is an environmentally sensible fuel for use in large fleet vehicles and heavy-duty engines.

Pivotal LNG is a subsidiary of AGL Resources Inc. while Encana Natural Gas Inc. is a subsidiary of Encana Corporation. AGL Resources is dedicated to giving a leg up to the use of natural gas for transportation.

"AGL Resources has made commitments to serve the needs of an emerging market around the use of natural gas as a transportation fuel," said John W. Somerhalder II, AGL Resources' Chairman, President and Chief Executive Officer. "This agreement follows those commitments, creating a progressive relationship with Encana that we believe will help to stimulate this new industry."

Liquefied natural gas is natural gas in a liquid form. It is clear, colorless, odorless, non-corrosive and non-toxic, according to the Consumer Energy Center webpage of the California Energy Commission.

To produce LNG, a process known as liquefaction is used. Natural gas is cooled to minus 259 degrees Fahrenheit. By this process, the gas, primarily methane, is cooled below its boiling point, resulting in the hydrocarbons, water, carbon dioxide, oxygen and even sulfur compounds being either reduced or removed. LNG has a lower specific gravity than water, so it will float if spilled on water and then evaporate as it warms.

The liquefied gas burns cleaner than petrol and has energy density equal to 60 percent of diesel fuel. Though it can be domestically produced, LNG is also imported from Algeria, Australia, Brunei, Indonesia, Libya, Malaysia, Nigeria, Oman, Qatar, Trinidad and Tabago.

Under the terms of this agreement, Pivotal LNG will supply up to 100,000 gallons of LNG per day to Encana over the next five years.

"This agreement provides Encana Natural Gas with a secure, long-term supply source of liquefied natural gas for its new LNG fueling stations," said Eric Marsh, executive vice-president, Encana Corporation & senior vice-president, USA Division. "Encana is committed to expanding the use of environmentally responsible natural gas and this is an important step towards building an infrastructure that will enable companies servicing the energy industry to convert their large-freight vehicles."

Pivotal LNG announced recently it is in the process of purchasing a 60,000 gallon-per-day LNG facility located in Trussville, Alabama, given the fulfillment of certain closing conditions, which include governmental approval. The Trussville facility will be AGL Resources' first LNG facility dedicated solely to the merchant market and will play a role in supplying LNG to Encana.

"At Pivotal LNG, we see the value of using LNG as a cleaner, domestic substitute for diesel fuel," said David Schultz, vice president, Pivotal LNG. "Pivotal LNG has already positioned itself as a player in the wholesale LNG market. We are a part of a strategy by our parent company, AGL Resources, to build a foundation to support new and creative ways to bring the many benefits of natural gas to the forefront of our nation's energy landscape."

LNG is generally transported in large double-hulled ships specifically designed to handle the low temperature requirements. The carriers are insulated to prevent any significant evaporation of the gas. These carriers are up to 1,000 feet long, requiring a water depth of 40 feet when fully loaded. In 2004, there were approximately140 LNG ships operating worldwide.

LNG creates a visible vapor cloud from condensed moisture in the air when it comes in contact with warmer air. As it warms, the vapor becomes lighter and rises. The gaseous vapor is only flammable in a mixture of 5 to 15 percent natural gas. It will not burn at a mixture less than 5 percent. If over 15 percent, there is not enough oxygen for it to burn.

The gas is only explosive if contained in a mixture as described above. LNG burns cleaner than diesel fuel and given its higher storage density, is a viable alternative when compared to compressed natural gas for heavy-duty vehicles. Best of all, LNG achieves significantly lower nitrous oxide and particulate emission levels than diesel in those same engines.