Canada Special: Pan-Canadian integration - Starting to build the grid foundation

Having ambitious national wind targets is one thing, but meeting them requires overcoming some significant obstacles. For Canada one of the hardest challenges is not just building sufficient electricity transmission capacity at reasonable cost, but ensuring the individual provincial networks can work in harmony.

WindVision 2025, released by the Canadian Wind Energy Association (CanWEA) in October 2008, sets out a bold target that would see 20% of Canada's electricity supplied by wind by 2025, representing a total installed capacity of 55,000 MW. This is an ambitious undertaking. At present, Canada's installed wind capacity stands at 2864 MW, enough to satisfy just over 1% of Canada's electricity demand.

To reach the WindVision target, Canada will need to add an average of over 3000 MW a year for the next 17 years, starting at 1000 MW a year and steadily increasing over time. The prospect of such rapid growth brings with it a number of significant questions related to social, economic and environmental opportunities and challenges. But of all the questions before us, arguably the most important is: What does it all mean for Canada's electricity grid?

We already know that higher wind penetrations are not really a question of technical feasibility. Integration studies worldwide have shown that wind penetrations of up to 20% can be achieved with relatively modest operational impacts, providing there is sufficient transmission system coverage and a large enough - and flexible enough - market. So the key questions come down to both operational and economic impacts: how will it change, how is the grid managed and how much will it cost?

Although several Canadian provinces have carried out their own wind integration studies, to date there has been no serious work undertaken that looks at integration from a pan-Canadian perspective. CanWEA recognised early on that without this technical foundation in place, WindVision 2025 would be very difficult to achieve. Over the past year, the association has been working hard to fill this knowledge gap by laying the foundation for a Pan-Canadian Wind Integration Study with support from the country's system operators and utilities. At the same time, we have realised just how complex an undertaking it is, and just how important it is to get it right.

Guiding principles

At an early stage, we recognised that there were a number of key considerations that would strongly influence our approach to the study. These guiding principles, discussed below, were gleaned from experience in other countries and from inputs of experts in the emerging science of wind integration, with Charlie Smith of the Utility Wind Integration Group owed particular thanks.

The first key principle is that it is critical to take a regional approach to wind integration. Few jurisdictions can be considered electrical islands. In Canada, all provinces are interconnected - often weakly - with both neighbouring provinces and bordering US states, with whom they interact for market or reliability purposes. In this context it is difficult, if not impossible, to consider individual provinces in isolation, particularly as more express an interest in accessing green energy markets in neighbouring jurisdictions.

Secondly, it is critical to have strong involvement from utilities and system operators. It goes without saying, but system operators and utilities need to be comfortable with the operational impacts of increasing levels of wind penetration on their systems. In acknowledging this, we realised the importance of having active, hands-on guidance from the best and the brightest among system operators and utilities across Canada and the US. So, while we realised that the pan-Canadian integration study could be initiated by industry, ultimately it has to be driven by system operators and utilities.

Another guiding principle is that you simply have to "go big or go home." Experience suggests that comprehensive wind integration studies require significant time and resources. In 2007 the US Department of Energy (DOE) undertook a comprehensive study to assess the implications of 20% wind in the country. Estimates are that this study cost upwards of dollars US 5 million, not including the cost of DOE staff time.

Lastly, you have to use the right methodology. The state of the art for wind integration has come a long way in the past five years. From this experience has emerged a standardised methodology to wind integration studies, centred around three key elements: development of a mesoscale wind plant output model with time series data that is synchronized to demand data; assessment of the operational impacts of wind integration at varying levels using a unit commitment model; and iterative assessment of transmission build-out requirements necessary to implement the integration scenario. Taking shortcuts on any of these elements risks compromising the results.

These principles provided a good idea of the desired endpoint for the pan-Canadian study. But where to start? We realised at an early stage that there were significant challenges in even defining the scope of work for the study. Firstly, although we were aware of certain provincial integration studies, we did not know how comparable they were and how much they could contribute to a national effort. What methodologies did they use? What data did they generate?

Secondly, we recognised that the ultimate goal would be to catch up to the US studies and eventually be in a position to merge our efforts with the US and assess wind integration on a North American basis. So we needed to determine not only where these studies are today, focused on the concurrent US Eastern and Western interconnect studies, but where they will be in one to three years when the Canadian study is completed.

Calling on experience

As a first step, we assembled a steering committee of high-level representatives from system operators and utilities in each of Canada's ten provinces. Recognising the experience of our US counterparts and the important north-south links of the study, we invited experts from the Midwest Independent System Operator, New York Independent System Operator, Western Electricity Coordinating Council (whose service territory extends from Canada to Mexico), the Utility Wind Integration Group and the American Wind Energy Association to participate. In its first meeting, members of the steering committee agreed that a wise first step would be to commission a study that could provide a lay of the land and establish terms of reference for the larger pan-Canadian study.

To undertake this, CanWEA has contracted Garrad Hassan to undertake a scoping study that would serve three essential purposes. It will provide the background context that sets the stage for a pan-Canadian integration study. This includes identifying what studies have been done in the past, what data has been generated, and where the US wind integration studies are headed and what would be needed to eventually merge with them. Next the scoping study will develop one or two scenarios of what the transmission build-out might look like in a 20% wind future. This "straw man" will help to seed the discussion for the larger study. On the basis of the above, it will then develop the terms of reference for the pan-Canadian integration study, along with an estimate of required resources.

Since June, Garrad Hassan has been working with CanWEA and the steering committee on the scoping study. Already we have encountered a number of issues that will, along with the guiding principles, have a great influence on the scope and execution of the Pan-Canadian integration study.

A key question is how will we define 20%? Early in the process, the steering committee considered how 20% wind penetration might be defined - 20% in each jurisdiction, each region, or simply nationally. We are proceeding with the examination of two options at this time: a 20% regional approach, wherein the best 20% of wind farm sites in each region are selected, and a 20% national approach wherein the best 20% of wind farm sites are selected in Canada, regardless of region.

Dealing with exports

Another question is how will we deal with exports? Here, two options exist. The first is to assume that the output of all wind generation in Canada is counted towards meeting the 20% target, even though in some locations, for substantial lengths of time, much of the wind generation is contributing in some way to export flows. The second is to assume that wind is the last plant on the system, so export from a province that occurs when wind is producing is assumed to be exported wind production, and is not counted towards the 20% target. While no decision has yet been taken, we are leaning to the former approach.

What data resolution will be required? Experience suggests that creating ten-minute data is not significantly more expensive than creating hourly data, though performing the analysis at ten-minute steps rather than hourly is significantly more expensive. Producing ten-minute data may have the advantage of facilitating integration with future US studies.

We also need to think about how to address interprovincial issues. This presents a considerable challenge as energy is primarily a matter of provincial jurisdiction, and the role of the federal government is therefore relatively limited. Without an equivalent of the US Federal Energy Regulatory Commission (FERC), issues around interprovincial transmission build-outs and control areas can be difficult to manage. This is notable in the case of Quebec, which does not have any synchronous ties to other jurisdictions.

It is expected that the results of the study will be released by November of 2009. At that point the terms of reference developed throughout the process will be used as the basis for a funding application under the federal government's recently announced Clean Energy Fund. Although Canada may be late to the game in terms of national wind integration analysis, we are confident that our current process, guided by a very capable steering committee, will yield results that are realistic and robust. With this foundation in place, we are confident that Canada will have the technical platform needed for the country's leaders to make continued strides towards the ambitious targets of CanWEA's WindVision 2025.