Last weekend marked the official opening of the first 250Kw turbine in Northern Ireland to be reduced by EWT from 900Kw to 250Kw. 

The replacement turbine, located in Cloughmills, is an upgrade from a Bonus 250 to an EWT 900.
It was commissioned by McGuckian brothers Brian and Liam with plans brought to fruition by 2020 Architects in Ballymoney.

2020 Architects are specialists in rural architecture and sustainable technology.  Directing Partner Michael Howe, member of the Royal Society of Ulster Architects, explains how wind energy, especially in the form of replacement turbines, is still an extremely lucrative market for farmers to tap into.

ROCs Incentives

As the farming community is well aware, the window of opportunity to benefit from Government incentives in the form of full 4 ROCs for new turbines is closing under the Renewables Obligation (Amendment Order) NI 2016 with the cut-off point April 2017.  However, if you have a fully connected turbine on your site by this time – incentives are still available to farmers for the next 21 years making now the best time to optimise your energy output.  The Orders set out that ROCs cannot be issued on generation that occurred beyond 31 March 2037.


Currently, the majority of existing turbines are standard models.  VESTA V27 and A27 produce an average output of 100kw/hr to 140kw/hr on most sites.

Michael adds that with a reasonable ROC value, now is a good time to think of a turbine upgrade.  “Under the Renewables Obligation (Amendment Order) NI 2016, farmers with wind turbines up to 250Kw can claim 4 ROCs for every megawatt hour of electricity produced.  As a generator you can enter into an agreement with an electricity supplier to sell any electricity to them that you do not use.  Currently, the value per issued ROC is £41.65 but we have seen this go as high as £50.”

Efficiency savings in your pocket

“If you’re considering a new wind turbine on your site – you must have your turbine up and running before April 2017 in order to tap into ROC incentives.  Replacement turbines are not restricted.” Michael advises.

“New EWT 900Kw turbines with 52m and 54m rotor diameters are extremely efficient turbines.  The larger blades improve the turbines power curve ensuring more output – in less time.  They can be clipped down at the ROCs cut off 250Kw –  meaning they are far more efficient turbines due to the massive blade span.”

“Essentially, farmers are wanting to increase profits from their turbine by making it yield more output – in less time.”

“It should be remembered that the exact turbine you get planning approval for is the turbine you must install due to the specific acoustic report submitted with the planning application.  A replacement turbine with a new specification will require a fresh new application.  2020 Architects offer a free feasibility survey and our services are available throughout Ireland.  We also offer free, impartial advice on sustainable technologies and replacement turbines.”


  VESTA V27 EWT Turbine
Generator Rating 225Kw 900Kw (with 250Kw digital restrictor
Rotor Diameter 27m 52m & 54m
Tower Height 31m 35m, 40m, 50m, 75m
Typical gross annual income £100,000 £215,000

*indicative comparisons