‘More efficient’ vertical turbines should replace traditional design on wind farms, researchers say

New research suggests the now-familiar sight of three-blade wind turbines should be replaced in future with more compact and efficient vertical turbines.

Not only would the design change result in smaller structures, but, if the turbines are strategically placed, they could enhance each other’s performance by up to 15 per cent, researchers at Oxford Brookes University claim.

The researchers used almost 12,000 hours of computer simulations to show that wind farms could perform more efficiently by substituting the traditional propellor type turbines for vertical axis turbines.

They said the research demonstrates for the first time “at a realistic scale” the potential of large scale vertical turbines to outcompete current turbine designs.

If laid in grid formations, the research team found that vertical turbines, unlike horizontal axis turbines, resulted in greater efficiencies, maximising their performance.

Professor Iakovos Tzanakis, who led the study, said: "This study evidences that the future of wind farms should be vertical.

“Vertical axis wind farm turbines (Vawts) can be designed to be much closer together, increasing their efficiency and ultimately lowering the prices of electricity.

“In the long run, Vawts can help accelerate the green transition of our energy systems, so that more clean and sustainable energy comes from renewable sources.”

The research team said that with the UK’s wind energy capacity expected to almost double by 2030, the findings are “a stepping stone towards designing more efficient wind farms, understanding large scale wind energy harvesting techniques and ultimately improving the renewable energy technology to more quickly replace fossil fuels as sources of energy”.

The team cited theGlobal Wind Report 2021, which states the world needs to be installing wind power three times faster over the next decade, in order to meet net zero targets and avoid the worst impacts of climate change.

Lead author of the research Joachim Toftegaard Hansen said: “Modern wind farms are one of the most efficient ways to generate green energy, however, they have one major flaw: as the wind approaches the front row of turbines, turbulence will be generated downstream.

“The turbulence is detrimental to the performance of the subsequent rows.

“In other words, the front row will convert about half the kinetic energy of the wind into electricity, whereas for the back row, that number is down to 25-30 per cent.

“Each turbine costs more than £2m/MW. As an engineer, it naturally occurred to me that there must be a more cost-effective way.”

The team said the study is the first to comprehensively analyse many aspects of wind turbine performance, with regards to array angle, direction of rotation, turbine spacing, and number of rotors. They said it is also the first research to investigate whether the performance improvements hold true for three VAWT turbines set in a series.

Dr Mahak, co-author of the research and senior lecturer at Oxford Brookes’ School of Engineering, Computing and Mathematics, said: “The importance of using computational methods in understanding flow physics can’t be underestimated.

“These types of design and enhancement studies are a fraction of the cost compared to the huge experimental test facilities.

“This is particularly important at the initial design phase and is extremely useful for the industries trying to achieve maximum design efficiency and power output.”

The research is published in the International Journal of Renewable Energy.