The ancient elements of fire and ice come together neatly in what could be the single greatest carbon-based energy source on the planet.
That resource is gas hydrates – natural gas that is bound in a matrix of frozen water under high pressure and low temperatures. To demonstrate the potential of this material, scientists will occasionally set it alight in the laboratory, creating the spectacular image of a flaming chunk of ice.
Researchers have discovered that some of the best conditions for the formation of gas hydrates occur on the seabed off continental shelves and in Arctic permafrost, meaning Canada likely has vast deposits of the resource.
Many researchers believe it is only a matter of time before gas hydrates are developed for their energy, but there is some question as to whether Canada will – or should – lead the way.
Carbon dilemma
At issue is the fact that gas hydrates are a carbon-based fuel. Assuming energy companies figure out how to economically unlock the natural gas from the ice – and many researchers think that will happen within 20 years – the burning of the gas will create carbon dioxide and hence contribute to global warming.
“It’s good to know that we have the gas hydrates,” says John Grace, a professor of chemical and biological engineering at the University of British Columbia and holder of the Canada Research Chair in Clean Energy Processes.
Society will likely never completely move away from carbon-based energy, he says, and natural gas – which is mainly methane – is at least a cleaner fuel than oil or coal. “But, to the extent that we can find alternative sources that are not based on carbon, and that we can reduce demand for energy, it would be nice to think that we don’t have to exploit gas hydrates.”
Dr. Grace recently chaired an expert panel convened by the Council of Canadian Academies to assess the potential of gas hydrates. The assessment was done on behalf of Natural Resources Canada, which wanted to know what challenges lie in the way of an “acceptable operational extraction” of gas hydrates in Canada.
The 13-member panel, which included scientists and industry representatives, concluded that Canada is well-positioned – if it so chooses – to be a world leader in the exploration, development and eventual production of natural gas from hydrates.
There are certainly many technical issues, but these are not likely to be insurmountable. Environmental and social concerns would be similar to those associated with conventional gas production.
The existence of gas hydrates has been known for almost 200 years. Chemists produced them experimentally in the lab, and oil and gas companies became aware of them around the 1930s when they began to notice gas hydrates forming in pipelines and causing blockages.
However, it wasn’t until the late 1970s that scientists realized gas hydrates exist naturally in the environment and are not simply a man-made phenomenon.
Estimates vary widely of the total volume of gas trapped in hydrates worldwide, but most scientists in the field believe that the energy value of gas hydrates is at least equivalent to, and potentially a full order of magnitude greater than, all conventional oil, natural gas and coal reserves combined.
“There’s no question it’s a vast resource, widely distributed,” says UBC’s Dr. Grace.
Canada’s research effort
Michael Riedel, a geophysicist at McGill University, conducts research using seismic data and drilling analyses to detect and quantify gas hydrates in the ground. Over the past 10 years, he has been involved in many of the major deep-drilling expeditions looking for hydrates.
Two areas of Canada where potentially large quantities of hydrates have been found are off Vancouver Island and in the Arctic, specifically the Mackenzie Delta and the shelf of the Beaufort Sea. The Mallik field in the Mackenzie Delta is one of the most intensively studied in the world, drawing researchers from around the world, particularly Asia.
There is also evidence that gas hydrates exist off Newfoundland and Nova Scotia, but research on the East Coast has been quite limited, says Dr. Riedel.
He compares the current state of gas hydrate development to where oil sands development was 20 or 30 years ago. At that time, people knew of the vast oil sands, but only a few companies were trying to develop ways to extract it. Most felt it would be uneconomical to do so. “We are more or less at that level with gas hydrates,” says Dr. Riedel.
Companies are starting to devise engineering solutions, but they have not yet tried to mass produce the gas because it is still cheaper to exploit conventional resources. Canada in particular “has the luxury of having choices. We have many different types of energy we can use.”
But that’s not the case for countries such as Korea and Japan with almost no conventional resources. “Those countries will develop energy from hydrates very soon,” says Dr. Riedel. “Their national programs are very ambitious,” investing tens of millions of dollars in research each year.
Dr. Riedel characterizes Canada’s own research effort as “too small.” There are a number of researchers at universities across the country doing work on gas hydrates, with funding “on the order of a few tens of thousands of dollars per year,” but only a handful whose research programs are devoted exclusively to the resource.
Renewed interest
Peter Englezos, a professor of chemical and biological engineering at UBC, has been studying gas hydrates since he was a graduate student in the 1980s and has seen the ups and downs in the field. He says Canada was a pioneer in this area and “has a distinguished record of achievement,” led primarily by the National Research Council and the Geological Survey of Canada.
Interest in gas hydrates grew after the energy crisis of 1973, but subsided with the collapse of energy prices in the 1980s, only to re-emerge in the past three years. A good measure of this resurgence are the 417 papers delivered at the sixth International Conference on Gas Hydrates, which Dr. Englezos chaired in Vancouver this past July. That compares to just 247 papers at the fifth meeting in Norway in 2005.
His own research has focussed mainly on preventing gas hydrate build-up in pipelines, but he is now devoting more attention to the development side. The resource “is not something that would be dug up, or mined,” he says.
Rather, researchers must find ways to release it from its solid form in situ and let it flow as a gas. “It’s doable. I can’t see why not. But it’s going to be expensive.”
Impact on climate change
If gas hydrates are developed as an energy source, the assumption is that the process will contribute to climate change. However, methane – the key ingredient in hydrates – produces less carbon dioxide per unit of energy than other carbon-based fuels.
So, if countries like India and China moved away from heavy reliance on coal and other “dirty” fuels, their carbon footprint could actually be reduced, says McGill’s Dr. Riedel. “It is like a transition fuel in my mind,” he says. “But in the end you have to realize that it’s another source of CO2.”
The issue is still too new for many organizations to assess. “I don’t really know what the environmental impact would be,” says Peggy Holroyd of the Pembina Institute, which advocates sustainable energy solutions. “That’s something that definitely needs to be examined in detail.” Similarly at the World Wildlife Fund of Canada, no one felt able to comment on the issue.
There is, however, a potentially more urgent threat: global warming could trigger the release of methane – itself a potent greenhouse gas – from gas hydrates located in permafrost.
“Permafrost is degrading rapidly, especially in Canada. And there is a lot of gas within the permafrost and below the permafrost [in the form of gas hydrates],” says Dr. Riedel.
The International Panel on Climate Change is said to be aware of the threat, but has not included gas hydrates in its climate modelling because there is still too little known about them to quantify the threat.