CanWEA 2009

I’m probably supposed to be on my way to the opening do, but I thought I’d post before it got too busy.

CanWEA 2009: Infinite Possibilities opened last night. Though attendance is up from last year, I think more people are coming into town today. It’s going to be a big event.

Energy Saving Trust’s field trial of domestic wind turbines

The Energy Saving Trust field trial of domestic wind turbines pretty much calls time on rooftop wind on the UK. Paul Gipe is less than impressed with the content and findings of the report.

Windsave, gone

Green energy revolution sours for Scots roof windmill maker – Herald Scotland | Business | Corporate & SME
Windsave, the high-profile Scottish developer of the ‘roof windmill’, has gone into liquidation

slightly past the use-by date

Just changed the batteries in my Mini Maglite. Check the battery date:

duracell install by jan 99I bought the batteries (and the torch) in an outdoor store in Truro, Cornwall in July 1993. I needed it to stop and start wind turbines at Carland Cross at night. The batteries still worked, if a little weakly. There are people driving younger than these batteries.

One of the batteries was, like Mr Belpit’s legs, a bit swollen with age. After several fruitless attempts involving rare-earth magnets and superglue, I took off the lens, bulb (well, LEDs)  and tail cap, and smacked it sharply against the floor. I could then lever the battery out with a sweetcorn skewer.

the nearest, uh, wind things to my house

Are on and by the garguntuan new Zellers:

wind things at zellersI hesitate to call them wind turbines, as they are pretty dismally sited. Doubt they’ll generate much. There’s also a wee solar array next to them.

bellamania

Bellamy calls for more sea power
Apparently, David Bellamy said that “if people wanted to help combat climate change they should wear an extra layer of clothing in winter”. Uh, what?

nine in the bed, and the little one said …

I don’t know if this is worth posting to RISKS:

I used to manage wind farm SCADA systems. The supplier is a market leader in the wind industry. The components used to feed data to the central SCADA are industry standard, accurate, reliable units. The complete cost of the SCADA system and associated metering probably runs into the hundreds of thousands of dollars. This isn’t el cheapo stuff, and is put together by knowledgeable engineers and technicians.

So I was a little surprised to see that the generation report for a wind farm was showing a total of -8.3 GWh, when a similar wind farm nearby had generated 1.8 GWh for the same period. What!? Crossed wires on the meter? Inconceivable!

No wires were harmed in the making of this error. For metering power delivered, power plants use interval meters, which behave extremely similarly to your household electrical meter. They’re a little more accurate, have a few more features (like these ones have ethernet ports for remote reading) but they’re basically the same: any energy that goes through the wires gets added up on a counter. Take two readings a known time apart, subtract the later from the earlier, and you’ve got the total energy delivered.

The wind farm’s SCADA polls this meter every ten minutes, and stores the result in its database. When you want a generation report, the server goes through the data, subtracts the last reading from the first, and presents that as the generation. Simple; what could go wrong?

The bods at Major Wind Turbine Company were baffled. I was confused, and a little annoyed as I had lender and a board of directors breathing down my neck for revenue numbers. So I dug into the raw ten-minute data, and found this:

kWh Delivered
Wind Farm A Wind Farm B
T=0 9523886 9999237
T+10 min 9525238 575
Difference 1352 -9998662

It doesn’t take a genius to realise that the meter at Wind Farm B rolled over at 9,999,999 kWh, and so should really have read 10,000,575 kWh. The poor little SCADA didn’t know to check for rollover, and happily subtracted the later number from the earlier.

I should add that there was no risk to public safety or system operation caused by this error. Just a few lost hairs from me.

(Actually, many years ago, I had access to the source of an extremely early wind farm SCADA server. It was written by a series of summer students, with variable names and comments in their native language. It was pretty hard to follow. One little nugget I did pry out of the code was that they used a simple arithmetic mean for averaging wind direction. That meant that it took the mean of 358° and 2° to be 180°; not so smart …)

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.

hot off the press: Green Energy and Green Economy Act 2009

Green Energy and Green Economy Act 2009.

(more at:Legislative Assembly of Ontario | Bills & Lawmaking | Current Parliament | Bill 150, Green Energy and Green Economy Act, 2009.)

no, I don’t have one. yes, I want one …

One of these turned up in our office today – the semi-legendary Lego #4999 Vestas wind turbine:

vestas-lego-4999

Operations guys need Lego too, y’know …

Wind, water and sun beat other energy alternatives, study finds

The best ways to improve energy security, mitigate global warming and reduce the number of deaths caused by air pollution are blowing in the wind and rippling in the water, not growing on prairies or glowing inside nuclear power plants, says Mark Z. Jacobson, a professor of civil and environmental engineering at Stanford.

lowville

(rhymes with how, not low, apparently)

I’m in Lowville, NY, tonight. I’m looking at wind turbines. In fact, if my room faced the other way, I probably would see them right now.

David Bellamy – Power From The Wind

Excerpt from the educational video made for the CEGB in 1989:

Local copy: David Bellamy: Power From The Wind (excerpt).

His views have changed a bit since then.