Nexen Inc. and Shell Canada, along with the Alberta Energy Research Institute (AERI), are studying the use of environmentally friendly low-enthalpy geothermal energy for oil sands (LEGO). Low-temperature geothermal energy, as it is also known, comes from underground sources less than 300 metres deep.
“Geothermal energy is a clean source of heat and could offset the carbon dioxide emissions caused by natural gas combustion,” says Rick Nelson, program director of water use and renewable energy at AERI. “In addition, geothermal systems that are integrated with a thermal chiller could be used to offset CO2 emissions which are by-products of electrical refrigeration.”
AERI’s research shows that shallow geothermal wells could provide space and building heating at oil sands facilities. The companies using it are now examining the potential of LEGO through an on-site demonstration of the technology.
Alison Thompson, project development manager of asset management at Nexen, says her company is interested in geothermal systems as a possible new energy source. “Nexen looks at a variety of energy alternatives,” she says. “In addition to our oil and gas portfolio, we also have power generation assets. This study appraises a new form of energy in the oil sands area that could make our operations more energy-efficient and reduce our carbon footprint and operating costs.”
Thompson says LEGO has potential benefits for the oil sands industry as a whole, too. “Geothermal energy allows more resources to be extracted from the same footprint because it can be harnessed in conjunction with other oil sands applications,” she explains. Thompson, who is also the chair and executive director of CanGEA, a not-for-profit association that promotes geothermal energy in Canada, is an ardent fan of LEGO. “Geothermal energy can replace heat and power that is derived from oil or natural gas,” she says. “Researchers are garnering the skills and experience needed to expand its use to other geothermal energy targets in Canada.” Her confidence in the technology is reflected by the fact that AERI put up one-third of the cash for the pilot project. Nexen and Shell together contributed the remainder.