Alberta's transmission policy makes it law to provide all generators with grid access, but it also requires that those loading the system pay the cost. Because of that, the challenge is to find the right balance to ensure "the transmission system is ahead of the curve, but not imprudently so," says Miller.
The AESO has been working with the province's wind industry to come up with a "credible solid forecast" for new wind generation coming online. In the mid-case scenario, he says, Alberta can expect to have 2000 MW of installed wind capacity in ten years and 4000 MW in 20 years. In the high-case scenario, it could be looking at up to 4000 MW of wind in ten years and up to 8000 MW in 20 years. "We're doing our planning around the mid-case and high-case scenarios," says Miller. The aim is to assess how much can move forward in the immediate term to establish what needs to be done to bring more online in future.
The AESO has hosted a series of open houses in the southern part of the province to collect feedback from residents and has met with provincial and municipal government representatives, industry stakeholders and First Nations groups. It is now revalidating its forecasts based on that input before proposing a series of alternative transmission solutions between mid-March and mid-April. Miller hopes the AESO will also be in a position to identify its preferred options.
The feedback has been generally positive. "There is a lot of enthusiasm in the south for wind generation. There are concerns as well. I am not going to sugar coat, but there is enthusiasm," he says. "The recognition that the infrastructure needs to be there to support it seemed to be fairly well recognised."
Approving new transmission in Alberta is a two-stage process, with the AESO first filing an application with the Alberta Utilities Commission (AUC) for approval of the need for grid upgrades. Then the transmission facility operator in the region where the upgrades are planned must file for a permit-to-construct and license-to-operate (P&L) based on its detailed siting plan for the new line. Miller says the AESO is hoping to file a need application with the AUC in May, although he admits it is an aggressive schedule that depends on how its consultations go.
Alberta currently has 524 MW of installed wind capacity and access to transmission has already become a major challenge for the province's wind power developers. The need for grid upgrades in the southwest part of the province was approved back in May 2005, but the AUC has yet to rule on the P&L application, putting desperately needed new transmission years behind schedule.
The AESO filed a need application in November for new transmission in the southeast, mainly to deal with customer load growth, but also providing access to 141 MW of new wind capacity, the amount that fits within a 900 MW wind power cap that was in place while work on the application was underway. The cap was lifted in late September.
Canadian Wind Energy Association's David Huggill is optimistic about the outcome of the process. "We are hoping and quite confident that the AESO will be able to look at things slightly differently than they might otherwise have done a year ago," he says.
Looking to the long term, a subcommittee of CanWEA's Alberta caucus submitted a report to the AESO in November outlining the elements of a 240 kV "transmission highway" for up to 3000 MW of wind generation in the region. Huggill says the study builds on the work done by the AESO in looking at transmission options for the southeast. "I think it is fair to say that we looked at it from the view that with a little bit more upfront cost and a little bit longer amortisation we might see some long term benefits specific to the wind industry."
CanWEA now plans to continue the analysis into the southwest of the province, says Huggill. "Obviously what takes place in the southeast will affect what takes place in the southwest. We recognize this type of planning has to take place in a holistic fashion from the system perspective." Miller says the AESO is taking a close look at the report's suggestions.