Is the data shown on the home page of Elotec Wind Turbines ( http://www.eoltec.com/ ) actually true?

It quotes 22,000 kwh @5.75 m/s in the Orkney Islands, surely no 6kw wind turbine could ever generate this much, given the quoted wind speed?
Surely the Orkney Islands would have a higher annual wind speed than this?

I heard recently, that the report was complied by some students, who got the data wrong/mixed up for this site,elotec know the data is wrong,but show it anyway ...as the report was by a third party...and they dont get the blame...apparently ;)

BTY this is not attempt to slander Elotec's turbine, as i actually think it's a very good machine, just questioning the report.

Any thoughs?

Anything this misleading on a company website should be investigated by trading standards.
People are genuinely investing considerable sums of money in equipment that they expect to perform close to a predicted amount for any given wind speed.

The graphic on the Eoltec webpage seems to be a direct link from the BBC webpage, and is shown on this page....

http://news.bbc.co.uk/1/hi/sci/tech/8139373.stm

I can only assume that the BBC got data directly from the EST, as no information like this was released in the "Location, Location, Location" report, nor was provided by Eoltec. In fact, if you scroll down to the second turbine picture (on the BBC site) it says there that the data source is EST, so I assume this is the case for both.

The best place to look for real life kWh data, is the likes of http://www.renew-reuse-recycle.com to see what real owners are actually achieving. Only problem with that, is that wind speeds for each site are generally NOABL estimates, but at least the kWhs being reported are accurate from the owners OFGEM accredited meters.

The EST data meantime is based on actual measurements that they took using anemometers and power transducers, so may be more accurate than NOABL. 22,000 kWh is certainly pretty feasible in Orkney - Highest producer to date has been one that did 25,500 kWh in a year. NOABL reports a 6.7 m/s site for that one. Not many of them (about 40 running on Orkney now) produce under 20,000 kWh per annum, and those that do are generally inland and in more sheltered sites, or have some terrain feature that induces turbulence from a certain direction.

To correct some errors in assumptions above.....

*Its Eoltec rather than Elotec - Seems to be a common mispronunciation!
*The default values in the spreadsheet show 6 m/s at anemometer height (10m) but the hub height is 18m, hence the uplift to 6.53 m/s. If you set anemometer height and hub height the same, then the figures tally. Databases like NOABL present data at 10, 25 and 40m levels, whilst tower heights are 12 and 15m. This function in the spreadsheet allows a correction for that.
*There is no cut out windspeed. Turbine keeps on running in whatever winds are thrown at it

The Eoltec spreadsheet is generally fairly conservative, which is good. People are delighted when the turbine that they thought was going to produce 15,000 kWh a year does 20,000 kWh! If you plug in the data for the site that produces ~25,500 kWh a year, the spreadsheet suggests 17,699 kWh. OK, so this is based on NOABL data (6.7 m/s) and estimates of turbulence intensity, wind shear exponent etc, but it is fairly normal, for Orkney at least, for the spreadsheet to be conservative.

Finally, its quite common for Eoltec turbine owners on Orkney to be challenged by OFGEM when submitting their ROC meter readings. Quite a few time now, OFGEM have not been able to believe the level of production being achieved, but are slowly coming round to the idea that these turbines are seriously productive!

No idea. Eoltec page just links to a graphic on the BBC page who appear to have got their data from EST who in turn arranged to have all the measurements done! EST are the only ones who carried out any measurements at that site so there is nothing to compare with - Just the readings they got with their anemometer. But they did use an anemometer, so its the best, if only, data there is.

There is however correlation with the EST's power claims, as the site also has an OFGEM accredited generation meter which fairly well matches the kWh that EST's power transducer has recorded.

I suggest you check with the BBC and / or the Energy Savings Trust then. All I know is that the EST commissioned the wind and turbine monitoring, and this was done with an anemometer erected for at least a year. BBC have published the mean annual wind speed in a news report, which they claim was sourced from EST. So you'll really need to contact the BBC about the wind data. It is the only wind monitoring that has been done on that site.

Plus, bear in mind that just because it says 6 kW "on the tin" doesn't mean to say that its limited to that! This turbine, along with most of the installed fleet use 2 x 3.6 kW inverters in tandem that allow net electrical output to run well over the 6kWe into the grid.

Pauler,

The answer we would give would be the same as we would all customers, potential or actual, that is, we would either point you to, or run over the spreadsheet calculator. This (assuming a few parameters you have not provided for your site), suggsts 13,848 kWh. With that, we would then suggest that you review actual figures as obtained by people on renew-reuse-recycle.com and strongly suggest you speak to a few (the more the merrier!) existing owners and ask them, anogst other things, how much energy they expected to get and how much they are actually getting. You could also ask them if they are happy that there is a difference between what they originally expected and what they are actually getting. I think you will then find that this is one of very few turbines where people are pleased with the difference, as opposed to the usual writings on forums like these where they are disappointed with it!!

So in answer to your question, we would say 13,848 kWh if that was the windspeed figure you were using, and then look forward to speaking to you in a years time following installation to see what you are actually getting!

Exactly, and this is what people like about them. A lower predicted output, and a higher actual output. At the end of the day, an OFGEM accredited cannot lie!

Posted By: Dominic CooneyAnything this misleading on a company website should be investigated by trading standards.

I don't know about trading standards but you can file ASA complaints online easily.

I'm waiting for them to process one I submitted recently about a company in a totaly different market.

We live in Mid Devon and have had an Eoltec Scirocco (15m mast) for 3 years. Our predicted wind speeds (NOABL, EST and Carbon Trust respectively) are 5.7, 5.5 and 5.1 m/s. Our annual output has ranged between 5400 and 6000 kWh per year, which is well below predicted.

The quadrants centred on SW, NW and NE are unobstructed, but the land rises slowly to the SE and there are sizeable trees within 300m. The landscape does have valleys, isolated trees and woodland, and the turbulence created is a problem for this type of turbine. It rarely stays at full output (6.3 kW) because a turbulent gust will hit the tail fin and slew it out of the wind. It then slows down and then speeds up once it has realigned itself. As a result the maximum sustained hourly output has rarely exceeded 4.5 kW (averaged over 2 - 4 h).

I have no doubt that the output would be much higher in "cleaner" wind. A smaller tail fin and some damping in the yaw bearing might improve performance by reducing the problem of slewing out of the wind under gusty, turbulent conditions.