Thumbs up for Offshore Wind!

If you want to work out how tall a wind turbine is at a distance, you can use simple proportion:

If I hold my thumb at arm’s length, it’s about a metre from my eye. The tallest a turbine would appear from shore would be equivalent to the height of the top joint of my thumb. That’s pretty small.

My comments on the “Renewable Energy Approval Requirements for Off-shore Wind Facilities”

Dear Mr Duffey

EBR Registry Number: 011-0089
Renewable Energy Approval Requirements for Off-shore Wind Facilities – An Overview of the Proposed Approach

I would like to propose that the mandatory 5km shoreline exclusion be removed entirely, for the following reasons:

1 Drinking Water Source Setbacks
While the “Technical Rules: Assessment Report”1 of the
Clean Water Act 2006 is cited as a major reason for the 5km shoreline setback, the assessment report itself provides for no greater setback than 1000m from a water intake in a Great Lake. It is suggested that this one kilometre setback be maintained for existing and planned intakes, but should not be applied as a blanket distance for all development. To force a larger setback than the Act allows is to discriminate against wind energy and the industry.

2 Lake Bathymetry

Taking the particular case of Lake Ontario near Toronto, the water depth at 5km from shore is typically2 40-70m. This is far greater than is practical, and would require massive and costly foundations.

3 Noise
The proposed shoreline exclusion unscientifically precludes any project coming closer to shore. As your document states that noise guidelines for offshore projects are in development, setbacks derived from these guidelines should be allowed. The document should also clarify that the 5km shoreline exclusion is typically larger than the setback required by the
Noise Guidelines for Wind Farms3, as at a recent MOE session on Low Frequency Noise Measurement4, representatives of “The Society for Wind Vigilance” stated that 5km was now the setback recommended by the MOE for all wind projects.

4 Positive Visual Enhancement
Wind energy is the most visual form of electrical generation, and it is a subjective matter as to whether the turbines are ugly or beautiful. The major shoreline constraint cited by the Ohio Department of Natural Resources is due to “aesthetic hindrance”5, yet the Great Lakes Wind Energy Center’s Final Feasibility Report6 wishes to site their pilot turbine as close to shore for “the highest iconic value”. Copenhagen, the capital city of Denmark, has an arc of wind turbines in the bay approximately 3km from the shore, and less than 5km from the Amalienborg Palace. By placing these turbines close to the city, they have made a statement of their commitment to sustainability, and avoided rows of pylons, which few (if any) could call anything but ugly.

I would hope that you would take my comments into account.

Yours sincerely,

Stewart C. Russell, P.Eng.

References:

4 12th August – 2300 Yonge St – 9:30-11:30am.

Continue reading “My comments on the “Renewable Energy Approval Requirements for Off-shore Wind Facilities””

Offshore Wind: much of Copenhagen is within 5km of offshore wind turbines

There’s a bit of a stooshie going on in Ontario renewables circles about a proposed 5km minimum shoreline setback for offshore wind turbines in the Great Lakes. This pretty much kills most projects through infrastructure costs — deep lake foundations are expensive, as is submarine cable. Please express your opposition.

I’ve flown over Middelgrunden, and found it to be an icon in Copenhagen’s harbour. With some freehand tracing in Google Earth and some minor GIS skills (hey, I’m learning), here’s how much of Copenhagen is within 5km of the turbines:

That looks like quite a lot; lots of homes and tourist attractions, and not just the harbour. If you want a closer look, here’s the buffer in KML format: Middelgrunden-5km.kml.

I’m trying to find the location of the turbine 500m from shore at Hooksiel, but maybe it’s a bit new for Google Earth imagery. Fixed that for me:

File: BARD Hooksiel 5km buffer.kml

a little bit on the toronto offshore wind farm and the Hélimax study

Many people (such as 1, 2, 3, 4) cite the Hélimax study Analysis of Future Offshore Wind Farm Development in Ontario [PDF] as a good reason not to even measure wind speeds off the Toronto shoreline. I would be quite surprised if most commenters had read it, as it’s not a light read, but there are three basic reasons that the report doesn’t apply:

  1. The report is not prescriptive; it does not outline the only viable sites in the Great Lakes. Indeed, the very last paragraph of the executive summary says “… it should be emphasized that the sites … selected do not necessarily correspond to the projects currently being developed. This report by no means seeks to disparage any sites currently under development which are not part of the 64 sites selected. There are wind power projects that can be feasibly developed beyond the sites that are identified in the present study.” A statement like that leads me to believe that the report was intended for capacity planning, and not site selection.
  2. The report specifically excludes Lake Ontario around the GTA on population density, even though it notes “… utilities generally prefer to have power generation close to population centres” [p.10]. Simply put, if Toronto Hydro wishes to bring wind power into Toronto, it can either have local generation where everyone sees it, or remote generation with pylons that everyone can see. Pick one.
  3. The mesoscale modelling that the report relies upon is unproven offshore: “… the accuracy of mean wind speeds derived from onshore mesomaps is generally assumed to be ±7%, the precision of such maps for offshore applications is not well known” [p.4]. ±7% for a mean wind speed means a lot more than seven percent in energy yield – that’s roughly good enough to tell you where you might want to start doing site selection. Indeed, the report confirms this: “… on-site meteorological measurements are required to perform a truly judicious assessment of the local wind resource and ensuing energy yields of a given site”.

So that about wraps it up for the Hélimax study pertaining to Toronto.

Others have commented that the low capacity factors of the Pickering and ExPlace turbines. Despite that fact that capacity factors for a given site are highly machine specific, there are some issues here too:

  • Both sites are near large buildings which disrupt air flow. This issue goes away even a moderate distance offshore.
  • Both sites are really demonstrators, and positioned for maximum public exposure rather than generation.
  • The Pickering Vestas V80 was a very early model of its type, and needed a lot of TLC to get operating. I wouldn’t call it quite a prototype, but it’s not far off.
  • The Pickering turbine is designed for windy (Class I) sites. It has shorter blades (80m diameter) and a bigger generator (1.8MW) than the turbines I’m most familiar with (82m diameter, 1.65MW). It will catch less wind and thus drive the generator less hard (quick, you come up with a better analogy for capacity factor … I couldn’t) than a Class II or III machine.
  • The Explace turbine has smaller blades than it was supposed to – the supplier ceased trading before they were able to replace the interim 52m blade set with 58m ones. As the tower was designed for longer blades, the turbine can never be run at full speed or full generation.
  • Due to the closure of Lagerwey, the ExPlace turbine has never had what I’d class as an industry-standard maintenance contract. The joint venture of TH and WindShare volunteers directs the maintenance, but there’s no permanent crew like a commercial operation would have.

So put that lidar out in the lake, and let’s see what we’ve got.