Working towards intgrating renewables

CANADA: Grid operators and industry are grappling with how to integrate the thousands of new megawatts of wind scheduled to come online in Canada over the next few years and set the stage for ongoing growth.

Balancing act: Canada’s grid has not kept up with growth of its wind market (Photo:David Dodge, Green Energy Futures)

Most additions are in Ontario, where the coming surge of renewable-energy projects, the return to service this year of 1.5GW refurbished nuclear capacity and lower industrial demand are causing concerns over surplus base-load electricity supply.

Ontario's independent electricity system operator IESO is consulting with industry on the best way to respond when generators that - for technical, legal or fuel supply reasons - have to produce more energy than the province can consume or sell into other markets.

Current market rules require the system operator to accept all energy produced by wind while conventional generating technologies have to respond to dispatch instructions every five minutes. The IESO wants to change the rules so that wind is dispatched too, which means it can be ordered to cut production during periods of surplus supply.

The issues being thrashed out include how to manage that process and how to compensate wind producers, whose power purchase agreements never contemplated the prospect of lost income from curtailment.

Ontario's situation is by no means unique. "There are other people moving in that direction," says Charlie Smith, executive director of the Virginia-based Utility Wind Integration Group. Major US markets like MISO in the Midwest dispatch wind according to its price bids.

In Canada, the Alberta Electric System Operator (AESO) is running a pilot project at two wind farms, looking at wind dispatch to reduce volatility on the system. Jacques Duchesne, manager of wind integration, says: "Within the hour the wind farms will be dispatched to a certain level and they won't be allowed to move from that."

Wind dispatch is only one option AESO is looking at as it works with industry on a long-term integration plan. The province currently has close to 1GW of wind on its system and by the time it gets to 1.5GW, likely sometime next year, it needs to have new tools in place, says Duchesne. Ancillary service products designed to follow the ups and downs of wind production and rules that provide opportunities for storage and load to help balance the system are also under consideration.

A large part of Alberta's challenges for integrating wind is that it has fewer ties to neighbours than most other provinces, making it harder to mitigate wind's variability. "Alberta is rather isolated, rather small. It doesn't have enough external transmission and has a limited market, which makes it difficult to integrate all the wind that it is capable of producing," says Smith.

Mirror image

In some ways, the province is a microcosm of the structural issues the entire country faces when it comes to maximising the use of its wind resource. "Canada is really light on transmission. Every province is its own zone, its own balancing area, they're much more strongly interconnected to the south than they are east-west," Smith explains. "More east-west transmission within Canada would give more opportunities for trading from one province to another."

The Canadian Wind Energy Association is looking for government funding for a pan-Canadian wind integration study that would look at the costs and benefits of that approach. "I think it would be very helpful to uncover the potential," says Smith. "Right now people are just guessing."

Before commenting please read our rules for commenting on articles.


comments powered by Disqus

Windpower Monthly Events

Search more than 4,500 companies in the Windpower Directory

Latest Jobs