Green Building Forum - Tesco Turbines

Tesco Turbines

StuartB — Wed, 10 Sep 2008 16:50:09 +0100

One of these has appeared outside my local Tesco store. They have obviously done their research and decided to choose this style of wind turbine over the more traditional design? Why? More efficient? Anyone have any more detail on these? Are they suitable for domestic installation?

They have also started turning out the lights on the fridges during the day so have now fully jumped on the green bandwagon.

Tesco Turbines

jon — Wed, 10 Sep 2008 17:07:21 +0100

They look good, make a statement and the design looks to me as if it would carry little risk

Tesco Turbines

jamesingram — Wed, 10 Sep 2008 17:14:52 +0100

I'd have thought its was purely for marketing purposes , probably not even wired in.

Tesco Turbines

CWatters — Wed, 10 Sep 2008 22:39:12 +0100

I'm surprised they left it grey and didn't paint TESCO on it in big red letters.

Tesco Turbines

joe.e — Thu, 11 Sep 2008 07:28:26 +0100

Posted By: jamesingramI'd have thought its was purely for marketing purposes , probably not even wired in.

I would have thought that having built the thing, the small extra cost of wiring it in would be paid off fairly fast. If it got built out of the marketing budget, the electricity generated would look cheap to the asset management people.

Tesco Turbines

Olly — Thu, 11 Sep 2008 08:58:25 +0100

Posted By: StuartBOne of these has appeared outside my local Tesco store. They have obviously done their research and decided to choose this style of wind turbine over the more traditional design? Why? More efficient? Anyone have any more detail on these? Are they suitable for domestic installation?

Vertical axis wind turbines (such as the Tesco one above) can work better in more turbulent urban environments where you don't have a predominant wind direction. In a steady breeze the horizontal axis (traditional 3 bladed ones you normally see) will generally be more efficient.

So this may well be the best design for this site, whether it's a good site or not is another question, whereabouts is it? I'd be interested to look it up on the DTI windspeed database.

As for wiring it, I'd be surprised if Tesco would really want to leave themselves open to criticism by having a huge white elephant outside their store. Plus they will want some media covage from it, so they're quite likley to be asked how much energy it produces.

Tesco Turbines

StuartB — Thu, 11 Sep 2008 09:42:23 +0100

I think they look great. I also agree that it MUST be wired in - what is the point otherwise. I saw it spinning the other day when I didn't think it was at all windy. Location is PH2 8DX.

Tesco Turbines

Olly — Thu, 11 Sep 2008 10:08:50 +0100

The DTI wind database says the average windspeed at 10m and 25m above ground level is 5m/s and 5.9m/s respectively, although those numbers should be taken with a slight pinch of salt.

Looks like it's located on the outskirts of a realtively urban location (south side of Perth) on Google, although the resolution is terrible in that part of Scotland so I can't see any detail of the surrounding landscape/buildings.

The trees and bushes in that photo certainly won't help with the airflow, so not an ideal location, but I've certainly seen worse. The vertical axis was probably the right way to go. I doubt it would payback within its lifespan purely on the return on KWh produced. However, I'm sure it's worth it when you factor in the marketing, plus there are possible grants, the sale of ROCs, and soaring energy prices to factor in.

Tesco Turbines

StuartB — Thu, 11 Sep 2008 10:19:36 +0100

Olly - this picture isn't the one in Perth, it was the only one I could find on the net. I think it's in Dudley. The Perth one doesn't have any trees nearby so should benefit from free flowing wind. Our part of the world is better viewed through microsoft maps rather than google.

http://maps.live.com/#JndoZXJlMT1QSDIrOERYJmJiPTU4LjQ4MjIwOTE5OTkzMzYlN2U0LjE1MjgzMjAzMTI1JTdlNTAuMDIxODU4NDE3NzM0NCU3ZS0xNS4yMjcwNTA3ODEyNQ==

Tesco Turbines

Olly — Thu, 11 Sep 2008 10:43:55 +0100

I've always liked Google software and found it very easy to use, so I never bothered to try the Microsoft alternative, but thanks for the suggestion, on this occassion it certainly is hugely better than Google maps!

Tesco Turbines

TheDoctor — Thu, 11 Sep 2008 12:00:23 +0100

If they are going for style over substance, and going for a bit of a green marketing drive, i have always preferred the thin bladed vertical axis turbines
like these:

http://ecotality.com/life/wp-content/uploads/2007/12/vertical_wind.jpg

Tesco Turbines

Pete1951 — Thu, 11 Sep 2008 12:50:24 +0100

Ropatec turbines are used in several countries, seem to be very robust and at least as efficient as the competition.

Tesco Turbines

Martian — Thu, 11 Sep 2008 22:08:51 +0100

Looks like a design based on the Darrieus wind turbine:

http://en.wikipedia.org/wiki/Darrieus_wind_turbine

Considering the expense of these things I would be very surprised if it was not being used to generate power.

Tesco Turbines

richy — Thu, 11 Sep 2008 22:42:04 +0100

It does look very much like one of those spinning signs that you see outside garages and the like! I once made the mistake of trying to stop one of those signs from spinning and recieved quite a wack! Is there a flywheel affect with wind turbines?

Tesco Turbines

ted — Thu, 11 Sep 2008 23:43:01 +0100

I have some rough 'real' numbers for a Tesco development:

Store size: 5,500 m2
Predicted energy demand: 4.2 million kWh per year (27% heating; 53% cooling; 12% hot water; 8% electrical)
Total predicted CO2 emissions: 1,400 tonnes per year
CO2 saving from Tri-Generation: 150 tonnes per year
CO2 saving due to wind turbine: 2 tonnes per year

Tesco Turbines

TheDoctor — Fri, 12 Sep 2008 07:48:23 +0100

'Every little helps'

Tesco Turbines

ted — Fri, 12 Sep 2008 17:20:27 +0100

I didn't have time to run those figures through a spreadsheet last night but it looks like they are expecting the wind turbine to generate around 5MWh a year which seems rather optimistic.

It will be interesting to check this against the ROC database in a year or so to see what they are actually making (assuming they go to the bother of registering).

Tesco Turbines

StuartB — Thu, 05 Feb 2009 16:19:36 +0000

The other Tesco store in Perth is now planning to put up another two of these 10 metre tall turbines. I have checked the windspeed for that store and it is 4.7m ps. I am not convinced that this is good enough, I was under the impression that you had to have a windspeed of at least 5m ps or there is no point in installing one. Looks like this really is just marketing BS.

Tesco Turbines

Matt — Thu, 05 Feb 2009 22:46:27 +0000

I wish they would learn to have doors that close to keep heat in in winter :|

Tesco Turbines

SimonH — Fri, 06 Feb 2009 00:08:53 +0000

Posted By: MattI wish they would learn to have doors that close to keep heat in in winter :|

LOL - i'm sure someone in the corporate sales team has worked out that if they have doors that close - customers won't come in and spend money.

I think all shops now need legislation - it's not just supermarkets: Easy learning Centre, Game, Orange, Vodaphone, O2, greggs and all by me always leave their doors open. Co-op don't, aned neither to boots, wh smiths, mcdonalds or sony centre.

But yes, super markets are worst. They should have flexi doors between the cold bit and warm bit so that the air isn't getting mixed, be forced to put doors on fridges and freezers and as an extra they could use the heat they extract from the freezers to heat the warmer part of the store.

But that would be to obvious!

Tesco Turbines

TheDoctor — Fri, 06 Feb 2009 08:05:16 +0000

it is marketing BS, of course, or they would build far larger centralised ones at, say, their distribution plants.

Oh, wait - no-one can see them....

good on-em if they actually work.
As long as they are not B&Q specials, and they achieve at least some benefit, can't fault them.

Simon H,

with high volume supermarkets, doors on fridges and freezers actually increase energy use.
the act of opening and closing a freezer door every 25 seconds warms the fridge unit faster than a well designed open display.

there should be thermal blankets etc overnight - yes.

Tesco Turbines

cookie — Fri, 06 Feb 2009 09:33:49 +0000

There are 3 approx 10 storey apartment blocks in Bradford which have these type of turbines on the roofs.

I don't know about efficency but shops use air curtains to help keep the heat in, you know the ones, you walk in on a red hot day in summer and its blowing hot air at you?

These are supposed to act as a barrier due to the fast movement of warm air, well thats my guess. I'm not sure how easy it is to close the door after every customer enters or leaves the store, not when you get 1000's of people an hour? But in quite times there is no excuse.

Cookie

Tesco Turbines

robJH — Sat, 07 Feb 2009 12:32:06 +0000

I would really like to see some performance figures on this turbine - it just looks wrong!

The main problem is the very (and I mean VERY) poor aspect ratio of the turbine blades. Looks like about 2:1 (height to chord (width)) - you really want a much higher value 8+ :1 to reduce the effects of over tip vortices. The post showing the quiet revolution turbine is much more like it - although there may be issues with swept blades on those turbines.

I should also point out that there is actually little information proving that VAWT are better than HAWTs in turbulent environments - a highly complex subject. Equally well, there is no proof that HAWTs are better that VAWTs at large scales even in steady wind flows.