
Study Finds Wind Speeds Are Increasing, Which Could Boost Wind Energy - PretzelFisch
https://www.wbur.org/hereandnow/2019/11/29/wind-energy-green-power
======
jacquesm
Windmills have several important speeds:

\- Cut-in speed

\- rated speed

\- shutdown speed

\- survivable speed

Cut-in speed is the speed at which the windmill starts to generate power,
rated speed is the speed at which it makes maximum power, shutdown speed is
the speed above which the furling mechanism can't operate or has no more
effect, which causes the machine the shut down (anything above rated speed is
essentially wasted), finally survivable speed is the speed which will not
cause damage to the machine.

If the wind speeds are increasing that's mixed news because you will make more
power between cut-in and rated, but given that the top end will likely _also_
increase and that wind power is v^3 the destructive force of that top-end you
might lose the machine entirely, only a very small relative speed increase
could make things go from survivable to catastrophic.

This is because all of these speeds given above are designed in to the system
when it is conceived and the survivable wind speed is not something that you
can easily modify once a machine has been built.

So mixed blessing, unless it is only in the mid-range and the top-end is
unchanged.

~~~
cheunste
I worked in the wind industry for a number of years and I have never heard of
anyone used the term "survivable speed" before.

~~~
jacquesm
That's funny, because I've designed a windmill from scratch and plenty of the
literature used that term.

I just checked Google to see if I'm mistaken but even the Wikipedia page on
wind turbine design uses it:

[https://en.wikipedia.org/wiki/Wind_turbine_design](https://en.wikipedia.org/wiki/Wind_turbine_design)

"For a given survivable wind speed, the mass of a turbine is approximately
proportional to the cube of its blade-length."

So I'm not sure why you've never heard that term but it definitely is in use.

~~~
strainer
I don't believe its a term in general use in the industry (of large wind
turbines). Since "survivable" means "might survive" \- that's not a very
useful engineering target. Wind turbines have to be rated to reliably
withstand specific gust speeds, so talk of certain speeds being "survivable"
should be non-technical.

Afaik modern turbines are specified to reliably withstand an "extreme 50 year
gust" estimated by their locales "Wind Class" [1] Some headroom is likely as
with all large constuctions, building, bridges.. The matter of what stronger
gust speeds might be survivable by the majority of installations is not
specified.

[1]
[https://en.wikipedia.org/wiki/IEC_61400](https://en.wikipedia.org/wiki/IEC_61400)

~~~
londons_explore
It is surprising to me that windmills seem to have such a large structural
headroom with this "50 year gust". Farms of windmills around me of 1000's of
units have had zero collapses. When your business is offshore wind farms, why
not remove all the headroom, make the structure far cheaper and lighter, and
aim for say 25% of windmills to collapse around 30 years? The cheaper capital
costs will surely pay for increased decommissioning costs of collapsed
windmills and loss of production 30 years later after compounded cost of
capital.

~~~
strainer
Heh, well maybe - adopt an Elon Musk development strategy : "Failure is an
option here. If things are not failing, you are not innovating enough." it
more than works for his projects, but if you're competing for policy support
and you happen to get your 20 year gusts this year it looks really bad, even
if a low percentage of turbines actually caught them from a bad direction and
happen to need new blades.

Also with offshore windfarms, the big extra expense is in installing the
towers and cabling. They are getting significant subsidy to be built for 15
year power purchase contracts, but once those towers and cables are built the
farm can remain very valuable at the end of the contract, if refurbishment is
required it could be remarkably cheap especially with a fleet of specialized
ships to it carry out, some of which are already at work putting them up.

------
danaliv
Nice to know I haven’t been imagining things! In 20 years of flying it’s
really seemed to me like I’ve had way more high-surface-wind days (which I’ve
arbitrarily defined as >20 kts) than when I started. It used to be a rarity
and now it’s well over half the days of the year.

I know there’s a lot of local variation, but even with that in mind it’s been
noticeable.

------
lukastr0
According to a two-year-old study, the opposite will happen and climate change
will weaken wind energy.
[https://www.theguardian.com/environment/2017/dec/11/global-w...](https://www.theguardian.com/environment/2017/dec/11/global-
warming-will-weaken-wind-power-study-predicts)

------
riffraff
There is a fairly interesting sci-fi story[0] about an ever-increasing world-
wide wind, I recommend it, and hope it doesn't go that way.

[0]
[https://en.wikipedia.org/wiki/The_Wind_from_Nowhere](https://en.wikipedia.org/wiki/The_Wind_from_Nowhere)

~~~
edzillion
There was also a sci-fi movie I watched as a kid that is set in a post-
apocalpytic earth in which a constant wind belt around the earth that people
'sail' to get around. Does anyone remember?

~~~
riffraff
I do not, but if you case about identifying the story, the SciFi SE[0] is
incredibly good at it :)

[0] [https://scifi.stackexchange.com/](https://scifi.stackexchange.com/) tag
"story-identification"

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arnoooooo
I understand the need for a study to quantify it, but I don't understand how
the increase itself can even be called a finding ?

I thought it completely obvious that there is more energy in the global
"climate system", so everything is amplified. When the sun heat is increased
on two surfaces with different heat capacities and albedos, the temperature
difference between them is increased, thus the pressure difference, thus the
wind.

What am I missing ?

~~~
pjc50
If you declared something this complex to be obvious, but you've not actually
measured it, then it's not a "finding" but a hypothesis.

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adrianN
We could also boost wind energy by just building more turbines. It's quite
simple.

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foota
Fascinating. It sounds like they believe this is a part of a normal ocean
pattern. I wonder what effect climate change will have on wind speed.

~~~
dwnwudp
So we design a global network of wind turbines so powerful that they buffer
climate change...like adding a huge mass to stabilize the dynamics?

~~~
krastanov
Nothing we do directly compares. For instance, the waste heat from coal plants
is insignificant compared to the energies in the atmosphere. Same with any
other energy scales we can reach with our technology. The climate emergency is
happening because we made a blanket to capture the energy of the sun on a
planetary scale, not because we directly added heat to the atmosphere by
burning stuff.

~~~
strainer
Studies are finding waste heat from thermo-electric plants may not be
insignificant. In this study [1] "energy consumption" is a shorthand for all
human heat emissions from combustion engines, industrial processes and thermo-
electric plant generation / consumption, etc. A large portion of human heat
release can be attributed to thermo-electric generation. Electricity
consumption accounts for 18% of energy use, with generation around 30%
efficient that means coal,gas and oil power stations account for somewhere
around half of global fossil fuel burn. [2]

From: Nature - A new global gridded anthropogenic heat flux dataset with high
spatial resolution and long-term time series (2019) [1]

> For example, Zhang et al.5 found that energy consumption could lead to
> increases in winter and autumn temperatures of up to 1 °C in the mid- and
> high latitudes across North America and Eurasia. Ichinose et al.1 found that
> the maximum anthropogenic heat flux (AHF) in central Tokyo, Japan, was as
> high as 1,590 W/m2 in winter, resulting in warming to a maximum of 2.5 °C.
> Moreover, anthropogenic heat can affect wind speed because it reduces the
> stability of the boundary layer and enhances vertical mixing. In view of the
> effects of anthropogenic heat on climate at local and continental scales and
> the increasing consumption of energy worldwide, the potential significance
> of anthropogenic heat as it relates to global climate change over a long-
> term period should be further studied using techniques such as global
> climate models.

[1]
[https://www.nature.com/articles/s41597-019-0143-1](https://www.nature.com/articles/s41597-019-0143-1)

[2]
[https://en.wikipedia.org/wiki/World_energy_consumption#Elect...](https://en.wikipedia.org/wiki/World_energy_consumption#Electricity_generation)

------
gorgoiler
An odd thing I learned about wind turbines recently is that their peak
efficiency is capped at exactly 16/27, or about 60%:

[https://en.m.wikipedia.org/wiki/Betz%27s_law](https://en.m.wikipedia.org/wiki/Betz%27s_law)

~~~
alphydan
it's not odd if you think about what that law is saying. The wind turbine
extracts kinetic energy from the wind. If it could extract 100% of the kinetic
energy, then the air would simply stop. So incoming air would "pile-up" after
the turbine (since it has v=0).

Since that is impossible, the air must have some speed after crossing the
turbine to make space for the incoming air. The details of that law are
simply, how much can you slow it down?

~~~
dTal
I think the odd part is the weirdly specific integer ratio with large-ish
numbers. You expect numbers like 1/2 and maybe 3/4 in fundamental laws, but
16/27 earns a double-take.

~~~
gorgoiler
This very accurately describes my own reaction!

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mycall
Then why are there reports that large storm systems (eg. hurricanes) are
slowing down and dumping more water and causing more floods?

------
OrgNet
it also could cause more wind damage...

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gitgud
As a kite surfer, this is good news.

~~~
wavefunction
Unless the wind gets too strong and you can't kite surf as much anymore...

~~~
mahesh_rm
Just get a smaller Kite.

------
TBtest
Wonder how long before increasing wind speed becomes a threat to tree
longevity

------
fouc
Global warming -> increased in wind speeds -> massive boom in windmill
construction -> extracting energy out of the wind causes slower wind speeds ->
Saves the planet from global warming.

~~~
98Windows
They extract an insignificant about of energy sorry

~~~
mikekchar
Kind of thinking the same thing, I once did a back of the napkin estimate of
the amount of energy entering the system just from global warming. Even if we
could use it effectively it completely dwarfs the amount of energy we use
globally. It really is astounding how little our current energy needs are in
the grand scheme of things.

------
caseymarquis
>>> Princeton University scholar Timothy Searchinger, one of the study's
authors, says researchers expect wind speed to continue to increase, he says,
which has multiple positive effects.

[https://xkcd.com/605/](https://xkcd.com/605/)

------
pizzaparty2
So the fossil fuel industry is behind the green energy movement? Those cunning
devils.

------
kumarski
Wind turbines are dirty sources of energy.

They do not supply consistent baseload energy.

Turbines are just giant machines built off the backbone of oil and natural
gas.

Humanity doesn't make turbines with renewable energy.

Trucks move steel. Earth movers navigate. Cranes push up structures.

All of this requires diesel fuel.

These figures aren't accurate, but precise enough.

Diesel ships transport critical turbine cement, steel, and plastics.

A 5 Megawatt turbine requires 900 metric tons of steel.

150 Tons - concrete foundations 250 Tons - rotor hubs and nacelles 500 Tons -
towers

Let's play with some scenarios w/ conservative back of the napkin
calculations:

If wind was 25% of global demand by 2030 *(w/ capacity factor of ~40%)

2.5 Terawatt hours of wind turbines require 500M tonnes of steel. (w/o towers,
wires, transformers. etc…)

30-40 gigajoules/ton are required for Turbine steel.

500M tonnes of coal to make this much steel.

60 meter foils. (theat each weigh ~20 tons) make up the 4 MW turbines.

Glass fiber reinforced resins are made of hydrocarbons.

Glass is made with natural gas furances.

The rotor’s mass of such a turbine is ~20 metric tonnes. (About 75 million
metric tonnes of oil)

Coal makes iron.

Coal + petro make kilns.

Naphtha and Liquefied natural gas make synthetic plastics for fiberglass.

Diesel makes ship fuel.

PS: In 2016, the global volumetric production of steel was ~1500 Million
tonnes. (+/\- 10%)

The wind turbine hydrocarbon based lubricants industry is fast growing ----
[https://www.globenewswire.com/news-
release/2019/02/20/173857...](https://www.globenewswire.com/news-
release/2019/02/20/1738574/0/en/Lubricants-for-Wind-Turbine-Market-To-Reach-
USD-226-1-Million-By-2026-Reports-And-Data.html)

~~~
Retric
While you’re numbers are wildly off base, that post represents a critical
misunderstanding of what’s involved.

Using hydrocarbons to make stuff has zero _direct_ impact on climate. CO2
requires carbon to end up in the air not turbines.

PS: Global annual electricity demand is ~21,000TWh. 25% of that is 5,250 TWh.
A 5 MW turbine at 40% average output produces 5 * 0.4 * 24 * 365 = 17,520 MWh
so you want 300,000 of them.

~~~
xyzzyz
_Using hydrocarbons to make stuff has zero direct impact on climate. CO2
requires carbon to end up in the air not turbines._

Where do you think CO2 ends up when you use hydrocarbon to make steel or
aluminum?

~~~
Retric
I was referring to his comment ‘The wind turbine hydrocarbon based lubricants
industry is fast growing.’ Talking about this as if it was a significant issue
is completely failing to understand what’s involved.

Anyway, it depends on what you’re doing, if your for example using coal to add
carbon to iron to make steal the it ends up in the steel. If you’re burning it
to make heat then it ends up in the air.

 _The average CO2 intensity for the steel industry is 1.9 tons of CO2 per ton
of steel produced. Taking into consideration the global steel production of
more than 1,3 billion tons, the steel industry produces over two billion tons
of CO2._

That’s ~5% of global emissions _per year,_ though looking at a number per
decade and comparing it to a number per year is rather big difference.

~~~
Gibbon1
I think with steel you can guesstimate about 4-5kwh per kg. The energy has to
come from somewhere. Right now it comes from coal and nat gas.

Reducing the carbon intensity of steel and also concrete production are things
that being worked on. Companies in those industries aren't willing to be
martyrs but unlike fossil fuel companies they aren't hostile either.

