Still, the remaining portion exists in highly usable forms (volcanic hot water and hot sedimentary basins) – an estimate that is borne out by geothermal research primarily carried out between 1962 and 1986, at which time the data collected was entered into a database to calibrate specific regions of Canada which researchers felt had the highest geothermal potential.
One of the extant sources was derived from the sampling of the log headers of petroleum wells drilled from 1939 to 2000, which calculated bottom-hole temperatures (BHTs), Drill Stem Tests, or DSTs, production tests, and downhole temperature logging.
In the final analysis, the report has determined that geothermal energy is broadly distributed across Canada, with specific regions having a slightly better potential than others. One such region is the Canadian Cordillera, which runs close to, although not directly along, the Pacific Coast.
Another is the Western Canadian Sedimentary Basin, or WCSB, a broad ridge covering 1.4 million square kilometers of Western Canada, including parts of Manitoba, Saskatchewan, Alberta, British Columbia, and a corner of the Northwest Territories. It is here that warm-to-hot fluids circulate through porous rocks which were once, and may still be, drilled to provide oil and natural gas.
Elsewhere in Canada, along both coasts and in a broad strip down the center often referred to as the Canadian Shield, cooler, dryer rock formations (sedimentary basins) hold the promise of greater use of ground source heat pumps or other forms of indirect geothermal energy.
Except for geothermal heat pumps, which are already being taken advantage of, Canada does not currently rely on geothermal energy for electricity generation, even though its high capacity factor and relatively “green” profile make geothermal an ideal replacement for those oil and gas resources.
In fact, geothermal’s only environmental impacts include the potential adulteration of groundwater or alteration of groundwater chemistry, the cooling of groundwater-dependent ecosystems, and modifications in groundwater flow patterns. Other deterrents include the potential for seismic events, increased noise levels, and the release of pollutants as supporting fluids or combustion emissions.
The real problems to greater geothermal energy uptake are accessibility and expertise. Many of the most likely areas are in remote northern communities, which don’t have a great need for power. There are exceptions, of course, notably Resolute Bay in Nunavut, which is highly dependent on expensive diesel fuel and would benefit tremendously from geothermal – even Enhanced Geothermal Systems (EGS) which don’t require water onsite or a highly permeable reservoir.
Other restraints are a lack of transmission lines and relatively primitive drilling technologies. However, if the resource could be capitalized, it would likely herald the death knell of highly polluting coal and highly dangerous nuclear power over a reasonable period of time, and alternate investment in geothermal.
To encourage advances and uptake, the study’s authors suggest a geothermal production tax credit to stimulate better technology, which will in turn lead to increased adoption of geothermal technology while also removing the drawbacks and uncertainty that result from public funding.
They also recommend a greatly enhanced national geothermal database which would reduce the seismic risk during exploration. So far, measurements include only principal stress magnitudes in designated areas (this information begins on page 142).
Another effective tool to bring geothermal energy to greater commercialization and uptake would be investigations that include combined field, laboratory and computer modeling. Also lacking, researchers note, is a regulatory framework to insure sustainable energy production with minimal environmental degradation.
Lastly, colleges and universities need to begin training a future team of geothermal experts to shape Canada’s clean energy future through geothermal energy.
Meanwhile, in the United States, the Department of Energy has announced awards of up to $38 million to advance geothermal research. One of the recipients is Lawrence Livermore National Laboratory (LLNL), which received $890,000.