top of page

It doesn't (always) depend on the size

Many streams can make mighty rivers. Same goes for the wind. There is a surprising amount of energy in many small mills working together – 10 times as much, in fact, as traditional turbines on the same piece of land.


There is lots of power in small things. Sometimes that is hard to forget. Oftentimes the bigger the better is the mantra. It does not have to be like that in the business of electricity. Certainly not when it comes to the electricity bills. Many are asking themselves about what to do about the coming shortage of energy as well as the soaring electricity bills... wait, the soaring and unpredictable electricity bills you might say: A problem that might last for years to come. 


Smaller, silent windmills  


There are many problems in the energy world. There are many questions, but also many solutions. One of them is smaller, silent, more bird and insect-friendly wind turbines that rotate vertically. Not horizontally, as we may be used to seeing on countryside fields, mountain ridges and in some rural areas. The VAWT (Vertical Axis Wind Turbines), as the smaller wind turbines often are called, looks like an eggnog whisk - but don't underestimate this way of making energy because of its cozy appearance and it's only eleven meters from the ground! 


3 x VAWT: Vertical Axis Wind Turbines are smaller windmills that resemble an eggnog whisk! But do not let the cute visual aspect fool you.

The energy output solution is not obvious 


A few years ago, a group of researchers at Stanford University in California, USA, took a look at these small turbines versus the big ones. To see which of them generated the most energy given the same size of playing field. You might think that the answer is obvious. Surely it has to be the big ones? But, no! Not necessarily. Not when you compare the big vertical ones with the small horizontal ones on the same patch of land. 


Let us explain: A VAWT has a cylindrical shape. The blades are aligned parallel to the mast on which the rotor is mounted. These “egg beater” mills tend to be much smaller than traditional “propeller” turbines, typically about 10 times lower in height, and produce only about 0.1 percent as much power per mill.


But.


Not if you make the right pieces of the puzzle in the right place. Meaning, putting a pretty bunch of small mills together in a small area, so that they can benefit from each other. Like migratory birds flying in V-formation. Or like steering a sailboat with the correct wind direction and angles. The dynamics of the wind can be played up and played well, so that the mills play off of each other. Even in semi-industrial areas, where they will not be as visible.


GRAY GIANTS: We are (too) familiar with these enormous wind turbines. But do they really produce that much more energy than smaller ones – in the same piece of land? No.

The surprising research signed Anna Craig 


Anna Craig, a PhD-student in mechanical engineering, figured out something super interesting. She, and her team at Stanford University, found that a bunch of small mills could generate 10 times as much power as large turbines on the same patch of land! This was – and still is – very interesting! 


Not only for the whole of humanity and large parts of the business world dependent on energy (who is not?), but also many small and medium-sized businesses along fields, coasts or connected to a small piece of land that can be used to become self-sufficient. 


10 times more electricity


What Anna Craig did was to prove with 1,300 gears, 30 rotating cylinders and several experiments in the laboratory of the Department of Environmental Engineering that vertical-axis wind turbines (VAWTs) have the potential to be a highly efficient energy solution when placed in densely packed groups. 


Because even though individual VAWTs don't produce anywhere near as much energy as the huge horizontal-axis wind turbines (HAWTs), the airflow and synergy between groups of small turbines can generate significantly more power per land area than the large turbines which require greater distance from each other. 


The study was published in the Journal of Renewable and Sustainable Energy in 2017 and received … some attention. But apparently not enough! 


The bottlenecks are mainly bureaucratic 


Have you seen many smaller wind farms like this in the British countryside? Well, no. Many who have tried to introduce a solution have gone bankrupt, because even if the knowledge and the will amongst the population are there – it's not easy to get permission. 


Sure, Anna Craig and the researchers wrote that “further work” was needed to understand the complex wind dynamics in nature and to develop efficient ways of positioning the turbines, but the results were so promising that several companies believed in and continue to believe in and develop what we can almost call “Wind 2.0”. 


So why is it so difficult? To set up your own wind farms that provide stable and affordable green energy? It's often a question of licensing. 


Today, it's possible to set up a single turbine or mill in the UK without asking anyone for permission as long as it is quite short and does not generate too much kW. But if you apply - you can apply for as many as you like - and if you get a “go” to put up 20 to 50 mills, you'll be able to help solve climate change and also ensure that you can sleep well at night, knowing that you'll have electricity tomorrow as well. 


Electricity that doesn't tear away the ground beneath your feet. With a wind farm like this, your numbers could break even in just 5 to 6 years.


ILLUSTRATION IMAGE: This is one of the many, many designs of a VAWT. Taking advantage of all sides of the wind.

The world needs smaller, local power plants


However, it's not just licenses and old fashioned guidelines that stand in the way of greener, more affordable electricity. Because if we suddenly managed to produce lots of free, green energy tomorrow, most cables and power grids would … explode. Kind of. They wouldn't be able to handle all the power. Here's why: There's not enough room for a lot more energy, and it will take many, many years to expand the electricity grid - regardless of whether the energy comes from nuclear, gas or wind. 


“The lack of capacity is the bottleneck in today's energy system. That's why it's high time to introduce distributed energy. The world needs more ‘energy behind the meter’, as in the use of smaller, local power plants,” says Carl Ivar Holmen, CEO of Norhybrid Renewables, a Norwegian renewable energy company that makes small, vertical wind mills intended to support solar panels and batteries to store green energy for maximum utilization. 


We think of tomorrow. Do you?

bottom of page