How many Windmills…? : The WindMill Index

I frequently run into the dilemma that we, in the ‘energy-intensive world’, want to switch to a sustainable approach, and want to switch to renewable energy sources, but that we absolutely do not want to give up anything of our welfare . Whether they are make sense or not. Take my earlier article about the clothes dryers. Why on earth would we build wind turbines to fuel dryers, while the same wind could do that directly on the clothesline? [1]

And when I started to make some more calculations, I got the idea to make things easier to understand. You probably know, the BigMac index, by which countries are compared in the economic field. Well, we can also make a comparison on the basis of renewable energy, because we all have to switch to renewable sources. And for that, wind farms and solar panels have to be built. So after some puzzling the “windmill index” was born.
We express all end functions and services in the amount of wind turbines that have to be built for that purpose.
The laundry dryers of the previous example were the first to be calculated . Roughly I arrive at 620 wind turbines, needed to run the dryers throughout the Netherlands. That’s huge, right?

A few comments I have to make: I assumed 100% penetration of clothes dryers, (with 1.65 kWh per turn, for a B/A+ machine, and at 200 turns per year, lifetime 10 years). Where the penetration is now only 60%. But I assume that the human aspiration for ever more will eventually lead to 100%, as it did with other devices. Moreover, with each device, a proportional share of generation capacity should in fact be included in the assessment.

As far as the turbines are concerned, I assumed a wind turbine on land of 2 MW, which was budgeted with 2000 full load hours , giving 4000 MWh per year of production. We can of course tinker with those starting points, but this seemed like a reasonable starting point. Firstly, the current windmills on land do not reach that 2 MW average yet, so we’re on the right side. In addition: a land turbine has much less impact, from materials and production, compared to a off-shore turbine. If we were to calculate the real impact, and I mean multiplying the Circular Energy, the energy to prevent the exhaustion of raw materials, and thus the energy for the stocks of raw materials to recover, then we can build very few wind turbines … [2]. That’s why I opted for a land-turbine, besides, we are also land-animals, and should not shift the burden on ocean animal life.
In addition, those 620 wind turbines only reflect part of the real impact. What is not included is the impact or loss of the electricity grid, or the impact of building the laundry dryers. Or in other cases all the impact of the end use itself. But as an illustrative indication the number of wind turbines is sufficient, it is already impressive enough, I think.
Especially if you know that in the Netherlands at the end of 2015 there are only 2500 Land wind turbines … Of this a quarter is already necessary exclusively for our dryers … Research shows that in principle there is space on land for sun 4250 wind turbines. [3] That is only twice as much. I think, there are more important things for which we can use the windenergy …

In short, the ‘windmill index’ was born.
Then lets explore some other services. What about all the doorbells that rely on the electricity grid via a transformer for 24 hours? They turn out to use 25 kWh on average per year. [4]. Multiply that by 7.5 million homes, that yields 187.5 million kWh, and requires another 46 wind turbines … There are alternatives, such as a pull or push doorbell , manually operated…

And now the energy companies want us to adopt ‘smart meters’. To ‘save energy’ . But these devices also require energy themselves, as well as research shows do not help us to save energy [5]. The only benefit is for the business case of the privatized energy companies. Then, how much energy do these meters themselves use? I did not find direct data, and had to estimate. On the basis of some Belgian figures, that it would cost about 20 Euro’s per year on the energy bill. At a Belgian kWh price of 27.5 cents I arrive at 59 kWh per meter per year. Based on this, 110 wind turbines are needed for these smart meters. Who or what is smart here?
(if someone has better data, I am happy to use them)

Anyway, smart in general only increases our energy consumption since it requires a lot of energy to collect and process immense amounts of data, via data centers and their networks. To give an example: The newest Google data center in Groningen runs on renewable energy, originating from the offshore wind farm above Delfzijl. [6] All electricity revenues from 19 turbines have been contracted for this for years, (plus a few more in Zeeland). And those are off shore turbines. In other words, the data park alone costs about 38 land turbines (about double) . And we already have 23 of those data centers …. that’s combined 874 wind turbines together, and rising. Long live the smart data-driven approach, the ‘internet or wind turbines’, IOW.

Now that we are looking into new smart solutions anyway, what about bitcoin, or better, the blockchain technology behind it? At this moment, every transaction in cash via bitcoin already costs 856 kWh. [7] After all, everyone has to digitally approve all transactions. Lets extrapolate that for the Netherlands in future, which has approx. 3200000000 financial (counter) transactions per year. [8] If we were to do everything via bitcoin later, 684,000 wind turbines would be needed …. They would not even fit in the Netherlands, even if we wanted to.

Ok, one more then, which is closer to the human perception: waterbeds …. They average around 1000 kWh per year. [9] No idea how many people have such a thing, could not figure that out, but let’s estimate that in 10% of all houses there is a water bed. (I assume 90% have used their senses …). Converted, 187.5 wind turbines are needed for this …


If I add all up, we will need 1837 wind turbines, each 2 MW (excluding bitcoin) , accounting for about 7500 GWh. There are currently about 2500, but they are not all 2 MW. Together they produce less than that 7500 GWh. In other words, all current land turbines are just enough to cover the luxury hobbies. We have not yet covered a single kWh of basic needs …

And then we have not yet mentioned waterpond pumps, night lights in front of and behind the house, leaf blowers, patio heaters, and more of that nonsense. (do not hesitate to add new data to this windmill index ….)

So let’s throw out all this fake use, before we count ourselves rich with a renewable energy transition. And mind, that whenever someone mentions the Nimby effect (No windmills in my backyard), ask if he abandoned all the fake use form his house, and has a Nimho certificate: not in my house.

[1] laundry article:

[2] Circular Energy:

[3] Ned. Vereniging Duurzame energie: “ In de studie ‘Klimaat, Energie, Ruimte’ van o.a. Wageningen UR wordt de potentie van wind op land en op zee berekend. Aan de hand daarvan krijgen we een beeld van de ordegrootte van het aantal benodigde windturbines op land en op zee. Volgens dit onderzoek is in Nederland ruimte voor circa 17 GW windenergie op land en 36 – 54 GW windenergie op zee. Met de grootte van de windmolens die vandaag de dag geïnstalleerd worden, komt dat neer op 4.250 windmolens op land en hooguit 6.750 windmolens op zee. “


[5] Smart technology in the home: time for more clarity, Sarah Bardy, BRI journal, March 2017:

[6] UK:




Author: ronald rovers