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MCS suspends Proven P35 and P35-2 wind turbines due to faults (revised)

Posted by Cathy Debenham on 27 September 2011 at 9:55 am

Proven Energy has gone into liquidation following discovery of an acute technical defect in its 15kW wind turbines (known as P35 and P35-2). Owners of the turbines are advised to temporarily brake them, and sales of these models has been suspended. MCS has suspended them from its accredited products list. The P-7 and P-11 turbines are not affected.

The fault is thought to be in the drive shaft, which needs strengthening to avoid metal fatigue. Repar of this fault is expected is expected to cost between £1,000 and £1,500 for turbines with and without the fault identified, according to a thread on the Green Building Forum.

The Microgeneration Certification Scheme (MCS) is liaising with relevant parties to co-ordinate the response to the situation. It advises people those affected to contact their MCS certificated Installation Company. Installation companies are in turn advised to contact their MCS Certification Bodies for further guidance.

Following MCS's suspension of the turbines no further installations of 15kW wind turbines (P35 or P35-2) commissioned from today onwards can be registered with MCS. This means they will not be eligible for the feed-in tariff.

KPMG, the receivers for the company, has set a deadline of today for bids to buy Proven Energy, and more may be known once a buyer is in place.

MCS has published the following Q&A, which seeks to address those questions that we are currently in a position to answer. There may be several left unanswered for those affected.

Why did MCS certify a small wind turbine which has subsequently failed?

The MCS tests and certification of wind turbines are robust and follow international and European standards. Certification cannot guarantee that products will not fail but it does give greater assurance. At this stage it is unclear why the products failed and we therefore await further information about the situation.  

Why was Proven allowed to remain in the MCS when it had a wind turbine failure over 18 months ago?

Proven did experience a wind turbine failure over 18 months ago but the company and their MCS Certification Body properly investigated this failure and carried out remedial action to the satisfaction of that MCS Certification body.

Does this wind turbine failure affect those consumers who have installed the Proven P35 or P35-2 and are receiving Feed-In Tariffs?

Generators who have installed the Proven P35 or P35-2 should follow the safety advice of braking those systems, and then contacting their installation company for further advice. As long as the installations are not generating they will not receive FITs. Until further investigations are completed into the technical problem facing these turbines, it is unclear what the long term future for operators of these turbines will be.

What should I do if I have purchased a Proven P35 or P35-2 turbine but not yet had it commissioned?

You should contact your MCS certified installation company for further information and not turn it on until the installation company have been informed that it is safe to do so.

When can I start generating again?

It is unclear at this stage who will be responsible for making that decision, as the company is now in the hands of the receiver Pending investigation of the technical issue, Proven Energy advised that the turbines should be shutdown.  You should liaise with your installer before restarting your turbine. Should remedial action be required we would advise that it be carried out by a competent and MCS approved installer. Anyone who chooses not to follow the manufacturer’s advice will be doing so at their own risk.

Update (17 October 2010)

Proven Energy has been bought by Kingspan Renewables, which will continue to produce the 3kW and 6kW models. It will decide at a later date whether to launch a 15kW model. People with any claims relating to warranties on Proven Energy turbines should contact the receivers at KPMG, and not Kingspan Renewables.


If you have a question about anything in the above blog, please ask it in the comments section below.

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6 comments - read them below or add one


pimmieComment left on: 29 May 2013 at 1:01 pm

`being a wind turbine virgin i have been assigned the role of getting that bl! turbine working again (everyone has run into blind alleys).

it will come as no suprise ! it,s a proven 15wt kw, all that is required initially is someone to come and assess what is needed and a decsion can then  be made on it,s future

we know quite a lot have been shut down, are you one of the lucky ones who are up and running again if so any any advice would be most welcome


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Richard Taylor

Richard TaylorComment left on: 30 June 2012 at 9:40 am

Dear Windy.....In the light of all the Proven tubine problems (which bear a striking resemlance to an american blogger's/first hand ex. Skystream employee's comments in 2009/2010 on the now MCS approved Skystream 3.7 - 2.4 Kw rated turbine)....have you got an overview from experience on either the present Skystream being marketed/installed over here in the UK now or the UK made Evance 5Kw turbine ?

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VickiBComment left on: 20 October 2011 at 3:54 pm

A series of roadshows has been announced for farmers keen to learn more about safe renewable energy options in the wake of the collapse of Proven Energy and Icon Energy.



Myriad CEG Power, the UK’s leading provider of onsite green renewable energy systems, has acted to tackle the difficulties and confusion created.



Farmers who already have Proven wind turbines on their land and want advice on what to do next – as well as those considering a move into renewable energy generation, are invited to attend the open days.



The first three are:



·         Wind Turbine Seminar and Open Day: Thursday October 27, Wilsey Down freehouse, Hallworthy, Camelford, Cornwall.



·         Solar PV System Open Day, Thursday November 3, Holmes Farm, Brant Broughton, Lincolnshire.



·         Wind Power Open Day, Tuesday November 8, Riplingham Road, Raywell, Cottingham, East Riding of Yorks.



Myriad works closely with Gaia Wind, which was the only profitable wind turbine manufacturer in 2010 and has a 14-year trouble-free track record.



For further information on attending any of the events, please contact Myriad CEG on 0203 167 0980.


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Cathy Debenham

Cathy DebenhamComment left on: 6 October 2011 at 10:43 pm

Thank you for the helpline number, Vicki. Very useful.

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VickiBComment left on: 6 October 2011 at 10:27 am

For those having difficulties with Proven Energy, Myriad have launched a helpline offering free advice and support on 0203 056 0874


Hope this helps

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WindyComment left on: 30 September 2011 at 11:31 am

I have supplied and installed over 100 Proven turbines over the past 18 years in the Falkland Islands.
Two years ago PowerSense and Proven parted company, the main issues were  the following quality standards and engineering defects:
Towers not fitting base plates
Tower top ends brocked with galvanising
Unmatched blades
Heat dumps with no terminals
Heat resistor with no protection ( fire hazard )
Incorrect rated CB's
No protection on the dc side in the controllers
Incorrectly wired volt and amp meters
Cable lugs crimped over the insulation
Diodes installed reverse polarity
48v system controllers supplied with 24v components
Controllers supplied with missing parts ( because they ran out of parts )
Winding (core) not fitting case
Incorrect air gap setting.
Price increases without notice.
Not honouring agreed pro forma prices.
Claiming fixes to problems when PowerSense had fixed the problem. ( Proven 7 battery charging turbine )

The first turbine I installed  (24v 2.2Kw) in 1993 was supplied with a controller that I had to rebuild.
The heat dump was a stainless steel box with two elements, no pre drilled holes and no terminals.
The last turbine I installed 2 years ago had incorrect rated elements for the dump load, 24v components in a 48v system, reverse blocking diode, and burnt out within 3 days of installation.

There is more but I'll leave it at that.

I reported all the above to Trading Standards in Ayrshire and the company based in Luton who were responsible for the ISO cert. that Proven Energy received,to no avail.

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