Tar Sands, Trailbreaker, and a Martian's Musings

Posted Wednesday, February 29, 2012 in Sustainable Maine

Tar Sands, Trailbreaker, and a Martian's Musings

Source: Florida State University

by Paul Kando

On February 9 a well-attended briefing was held in the Glickman Library of the University of Southern Maine. Organized by the Natural Resources Council of Maine (NRCM) and the Sierra Club, its purpose was to rally opposition to the oil industry’s Trailbreaker Pipeline, in part a massive project to expand exports of tar sands oil from Canada to the United States. With the Keystone X pipeline temporarily delayed, this project would reverse the flow of an existing pipeline system in Canada and Maine. The Portland to Montreal pipeline, designed to ship oil from the port of Portland to Montreal, is a critical segment of this pipeline. The idea is to ship tar sands crude from Alberta to Portland.  Once in Maine, it would be loaded onto tankers to be shipped to refineries along the Gulf of Mexico.

Unlike conventional oil, tar sands crude comes from bitumen, a hydrocarbon found mixed with sand and clay beneath Canada’s boreal forests, the largest remaining ecosystem on Earth comprised of pristine woods and wetlands. The open pit mining scars that already gouge the soil of Alberta are so huge they are visible from orbiting satellites. If tar sands growth goes unchecked, an area the size of Florida will become a wasteland.

Environmental concerns aside, an imaginary Martian watching this destruction and listening in on the chatter from Earth might wonder what Earthlings might be thinking. He might wonder about the oft-repeated claim that the purpose of tar sands oil pipelines to the U.S. is to secure a reliable “domestic” energy supply, when in reality all oil is a commodity traded on the world market, extracted, refined and shipped by multinational corporations to wherever it is most profitable. A large percentage of U.S. refinery production, for example, is diesel fuel for which greater demand exists in Europe and it is routinely exported there.

Bitumen is a sticky, black substance reminiscent of asphalt. It is separated from the sand and clay with the aid of copious amounts of heat. The source of this heat is liquefied natural gas. The bitumen is too thick to be conveyed by pipeline, so it must be diluted by the addition of more natural gas condensates. Natural gas is a cleaner burning, higher quality energy source than petroleum, yet it is used here to help extract this dirtier fuel which, when burned, emits 36 percent more carbon dioxide, 38 percent more nitrous oxide, and its sulfur dioxide emissions are also higher. The natural gas diluent content of tar sands crude can approach one-third. In short, a number of highly energy-consuming steps must be taken before tar sands, as mined, yield a product suitable for processing in an oil refinery.

Our Martian might wonder if this process is worth it at all. What is the energy return on energy invested in tar sands oil – how much useable energy is acquired from the tar sands compared to the energy expended in turning that substance into petroleum?  It was this question Christopher Peter of the British Columbian engineering firm C. J. Peter Associates addressed in testimony to the Joint Review Panel for the Enbridge Northern Gateway Project in Prince George, British Columbia on January 18, 2012.

Peter set out to document the energy required to make a barrel of crude oil’s worth of bitumen-bearing tar sand suitable for refining and deliver it to a state of the art oil refinery. He calculated the energy requirements of extracting the bitumen from the tar sand; transporting natural gas condensate by tanker to a Canadian port of Kitimat, B.C. and thence via the Northern Gateway pipeline to a processing facility in Bruderheim, Alberta; the energy required to transport the diluted bitumen by pipeline and tanker to a refinery; and the energy it takes to process the diluted bitumen to the point where it can be further refined along with ordinary crude oil. Refining of the tar sands crude was not included in the calculations.

Is it worth it?

Peter’s calculations start with 6.142 gigajoules, or 1706.17 kilowatt-hours, the standard used by the oil industry to define the energy content of a typical barrel of crude oil. From here he follows major steps of the process, from mining the tar sands all the way to delivering syncrude oil to a refinery. Peter uses various international (metric) units of energy throughout his testimony. For convenience I use kilowatt-hours (kWh), a familiar unit from our electric bills.

Eighty percent of Canada’s tar sand oil reserves are processed in situ, the remainder is open-pit mined.  In situ processing involves steam being pumped into a horizontal bore to melt out the bitumen from the tar sand.  The molten bitumen is collected in a neighboring bore, whence it is pumped to the surface. In open pit mining, the bitumen-bearing tar sand is transported in super-sized dump trucks to a processing site where it is crushed and the bitumen is separated using large amounts of hot water.

The tailings of this process contain huge amounts of heavily contaminated water, which is stored in vast unlined pools. These lake-sized pools abut once-pristine rivers, the sole water source of aboriginal people native to the area. The sand and clay are returned as fill to the strip mining site.  These processes use natural gas, mostly methane (CH4), as the source of heat. There is also a marginal amount of pumping energy required. The energy penalty imposed by all this is 347 kWh per barrel, reducing the net useful energy in a barrel of diluted bitumen to 1359.17 kWh.

Diluted bitumen (also known as dilbit, syncrude, or tar sands crude) is a mixture of hydrocarbon diluent and bitumen. The proportion varies with bitumen viscosity, but it is typically 30 percent diluent to 70 percent bitumen. The diluent comes from condensates of natural gas shipped to Canada by tanker from as far away as Australia.  Meanwhile much of Canada’s crude oil is shipped by pipeline to port and thence by tanker mostly to China. The total energy expended in the tanker transport of dilbit to China, condensate from Australia, and the return of empty tankers comes to 18.44 kWh per barrel, reducing the net useful energy per barrel of syncrude to 1,341.26 kWh.

Diluent recovery is another extra processing step not required in conventional crude oil refining. After pipeline transport, 70 barrels of diluent is separated from every 270 barrels of bitumen and returned back into the condensate stream. The process consumes 157.5 kWh. per barrel, leaving 1,183.76 kWh net useful energy.

Excessive sulfur content must also be reduced. This is done by adding of hydrogen in a process known as hydrocracking, which requires a further energy expenditure of 244.86 kWh per barrel, leaving 938.9 kWh of useful energy in a barrel of syncrude.

To sum up, of 1,706.17 kWh of energy contained in a barrel of typical crude, the extraction and processing of tar sands crude to the point where it can be refined consumes a total of 767.27 kWh per barrel, leaving only 938.9 kWh per barrel useful energy. This means that for every oil gallon’s worth of energy invested, tar sands yield about two gallons of net useful energy. Compare this to ordinary crude oil of which today 14 barrels are produced for each barrel’s worth of energy invested. On the other hand, the same one barrel used to yield as much as 100 barrels of 1930's Texas crude. Our Martian might ponder that if oil were priced in proportion to the energy it takes to produce it, tar sands oil would cost seven times more than the current price ($105 per barrel) of ordinary crude, or $735 per barrel. Regardless of how the industry prices its oil, one thing is certain: adding tar sands oil to the worldwide mix of crudes is bound to make oil more expensive.

The calculations above do not take into account the energy embedded in the infrastructure required to extract and deliver oil, or the energy lost in its end use. Nor are the high statistical likelihood of a spill or accident during tanker transit and the energy inputs of dealing with such events considered. A major oil spill and fire, China’s worst ever, did already occur in the port of Xingang. After 18 months, that spill has still not been cleaned up because, diluted bitumen being heavier than water, it could not be contained by any of the customary methods. Nor do these calculations reflect such social and environmental costs as the destruction of the boreal forests as a resource, habitat and a carbon sink, the jeopardy of multiple animal species, the despoiling of rivers and fresh water sources, the health impacts on indigenous peoples, and so on.

Easy access to tar sands oil by pipeline is likely to foster greater American oil dependency, postponing any serious progress toward an alternative energy-based, sustainable economy, even though such a delay will only make the eventual transition more difficult and expensive to accomplish. Yet at the standing room only meeting at the February 9 Glickman Library meeting, in spite of several pointed questions from the floor, there was scant mention of either the pitiful energy-economics of tar sands oil or alternative energy sources available to Mainers.

Our imaginary Martian might wonder if we Earthlings comprehend that tar sands oil is a “viable” product only to the extent society is willing to subsidize it. He would see the mining of tar sands to get oil as not only an environmental folly but also a sign of desperation on the part of the captains of the oil industry trying to prolong the flow of their profits, even while scraping the bottom of the oil barrel, so to speak. Is tar sand oil recovery even in the long term interest of oil companies, or is it just personally profitable, short term, for their top managers? And, concerning the Glickman Library meeting, our Martian might wonder if it wouldn’t be more effective to fight for a comprehensive alternative energy policy than rally against a pipeline.

True Alternatives

But are there viable alternatives for oil-over-dependent Mainers? Here is a sampling:

Applying passive house principles, we can reduce our home heating energy load by as much as 90 percent and make up for the balance with any of a variety of renewable energy sources. Even with do it yourself efforts we can reduce the heating load of a typical house by 50 to 70 percent.  Considering that the average Maine house consumes around 1,000 gallons of fuel oil, this would mean displacing between 500 and 1,000 gallons of oil a year per house. Assuming 500,000 homes statewide that translates to 250 million to 500 million gallons (5,952,381 to 11,904,762 barrels) of oil per year displaced permanently

Converting home heating boilers and furnaces from oil and gas to wood pellets – the technology is here to allow automatic operation similar to those of oil burners – would displace the remaining oil need up to 5,952,381 barrels of heating oil used in our houses with a fuel that, for the same energy yield, costs about half as much as fuel oil. Not a bad pay for the minor task of removing ashes several times a season that home owners would have to perform.  

Solar and wind power, solar water heating, the use of super-energy-efficient heat-pumps, heating with off-peak electricity and more could all be included here, not to mention firewood.

We know from worldwide experience that we can reduce our transportation energy as well, by as much as 70 percent. Assuming one 15 gallon fill-up per week, Maine’s 900,000 licensed drivers use 13,500,000 gallons of gasoline or diesel per week, or 702 million gallons (16,714,286 barrels) per year. A 70 percent savings translates to a permanent reduction in oil consumption of 11,700,000 barrels per year.

What about the energy economics? No room for detail here, except for this: While the energy penalties inherent in tar sands oil are incurred, barrel for barrel, as long as bitumen is mined, refined and burned, investments in energy conservation, solar and wind energy are one time investments, at least over the lifetime of a building. Firewood and wood pellets are renewable resources, as long as the forest is managed and the trees are replaced. Pellets are made from wood waste products whose energy penalties must properly be accounted for in the making of such primary products as lumber, plywood, paper and furniture. Likewise investments in converting transportation to more energy efficient modes and renewably generated electricity, result in permanent reductions in the use of petroleum. And all these investments generate much needed jobs – a huge and necessary social benefit, no matter how it is counted.

The threatened pumping of tar sands crude to Portland and the Gulf is as good an occasion as any to explore such issues further. Indeed, our Martian may ask, when will these Earthlings begin to approach society’s survival and sustainability using the powerful brain they each possess, instead of deferring to the powers that be for answers?

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