Canadian independent Cenovus Energy is looking for more ways to improve operations at its ever-expanding Christina Lake steam-assisted gravity drainage oil sands project in northern Alberta, with a fifth phase due on line this summer.
Christina is considered to be a top-tier reservoir with room to grow, and is becoming a proving ground for new technologies.
Four phases are already in operation — each with a design capacity of 40,000 barrels per day — and current production is running at 98,000 bpd from 65 wells.
Another four, 40,000 bpd phases are in various stages of development.
The latest, phase E, is expected to come on line in July or August and will take the project a step closer to its overall planned capacity of 300,000 bpd.
Since it began operating in 2002, Christina and its sister project, Foster Creek, have proved to be the feathers in Cenovus’ cap.
At Foster Creek, which is producing from five phases, output is running at 120,000 bpd from 217 wells.
The reservoir is not considered as good as Christina, but the Canadian player and its 50:50 joint venture partner, ConocoPhillips of the US, have already laid the groundwork for the next five phases to reach an ultimate capacity of 310,000 bpd.
Christina Lake’s director of operations and production, Greg Fagnan, said: “The reason we choose (to build in 40,000 bpd increments) versus going at 120,000 bpd all at once is because we’re able to tweak things as we go, based on lessons learned.
“If you’re building a facility from scratch to 120,000 bpd, you’re set with your design, and whatever decisions you make you are left to deal with either by sustaining capital down the line or through optimisation projects.
“By going at it in phases... our reaction time to something we’ve learned is almost instant.”
Those lessons have steered the company in the direction of new innovations, such as its patented Wedge Well technology, which helps increase total recovery of oil while lowering its environmental impact.
Operations require less water to be turned into steam to pump the oil to the surface, which means less water used and less fuel needed to create the steam.
Unlike oil sands mining, SAGD does not require large quantities of fresh water in its operation.
Only 0.07 barrels of fresh water are required for one barrel of oil using SAGD at Christina, with the majority of water used being brackish. About 90% of this brackish water is recycled, and 100% of that is re-used to steam, according to Cenovus.
Fagnan quipped that Christina Lake is more of a “water treatment facility with oil” than anything else. Cenovus is also piloting the use of a solvent-aided process at Christina to maximise the amount of oil recovered.
This process combines solvents such as butane, with the steam from SAGD to bring the oil to the surface. “Some of the lessons learned are game changers, like getting us from zero production to 40,000 bpd in six to nine months versus 36 months. That’s a huge difference,” said Fagnan.
“Because we’re pushed to try things on a commercial scale in pockets, we can see the results and ask when we can apply this to the next 40,000 bpd phase. The answer is immediately,” he added.
Cenovus has seen steady growth in its in-situ operations since it split from Canadian natural gas major, Encana, in 2009.
In 2011, chief executive Brian Ferguson announced that the company’s production goal is to achieve 500,000 bpd net by 2021.
Phases F and G are in the regulatory stage, with first oil due to flow in 2016 and 2017, respectively, while phase H is still bein planned.
At Foster Creek, phases F, G, and H are due to come on line in 2014, 2015, and 2016, respectively.