Yukon Electrical Co. has plans to upgrade one of the turbines in the Watson Lake power plant to run on a mix of natural gas and diesel.
The initial plan is to retrofit one of the six diesel-fired electrical generators to a bi-fuel system.
The project, a partnership between Yukon Electrical, ATCO Gas and ATCO Energy Solutions, has been submitted to the Yukon Environmental and Socio-economic Assessment Board for review.
If approved, the conversion could be completed by the middle of 2013. If that goes well the companies have plans to convert the other five turbines at the 5.5-megawatt power plant the following year.
The gas, which is cooled to minus-162 C, would be trucked to Watson Lake from a plant in southern B.C. in double-walled cryogenic trailers.
Because the gas is shipped in a liquid state, storage tanks and gas vaporizers would have to be built on site as well.
“This is the first of its kind for any one in the Yukon,” said Wayne Morishita, the director of marketing sales for ATCO gas. “We see a lot of opportunity in the North.”
ATCO’s role would be to handle all of the storage and vaporization requirements for the project.
Natural gas, which is essentially pure methane, is cheaper and cleaner burning than diesel. However, unlike diesel there is no established supply chain for the fuel.
While there are thousands of natural gas wells in northern B.C., the only liquefaction plants are in the southern parts of the province.
That’s one of the reasons that the utility is looking to put in a bi-fuel system rather than pure LNG, said Dwight Redden, general manager of Yukon Electrical.
Running both fuels means that if the supply chain for LNG were disrupted for any reason, the generators could just switch back to pure diesel, he said.
In addition, only slight modifications would have to be made to the existing diesel generators to allow them to run on both fuels, which is a much cheaper option than replacing them with new ones that run on gas - although just how much the conversion is going to cost is still being worked out, said Redden.
But while the cost savings are unknown, the savings in emissions are well established.
By replacing 50 per cent, or 2 million litres, of diesel a year with natural gas, the expectation is that it would reduce the carbon dioxide emissions by 300 tonnes per year.
Emissions of nitrogen oxide, soot, and sulphur dioxides are expected to decrease as well.
But while natural gas is cleaner burning than diesel, it’s still far from clean.
In fact, emissions of unburned hydrocarbons and carbon monoxide are expected to rise after the retrofit. In the case of carbon monoxide, the increase is “expected to remain well below Yukon air quality standards,” states the companies’ YESAB submission.
There are no standards in the Yukon for unburned hydrocarbons. However, while the “increase may be considered to be relatively high, the actual quantities are expected to be low,” states the filing.
Moving to renewable energy is ideal, but those kinds of projects - wind or hydro - take a lot of time and money to get off the ground, said Redden.
“Not to say that LNG will only be an interim solution, but it’s something that we can do now,” he said “The technology’s available, the costs look positive, the emissions results are encouraging, so that’s why we’re going there. But we’re still interested in renewable energy options.”
YESAB will accept comments from the public on the proposal until April 25.
Contact Josh Kerr at
joshk@yukon-news.com