THe ROI in terms of wind turbines's energy return after production is 5-12 months. It includes making them, serviceing them for lifetime and recycling
However there are downsides. Let's look at the theorethical turnout from wind power:
P = 1/2 ( A * p * Vwind³)
A = rotor surface area
p = air density
Vwind = air velocity
In easy terms this simple equation tell's us that the energy output depends on the windspeed, to the power of three(^3). This in return is dependant
on the location. We can determine that the rotor length influences it to the power of two(^2) because of the surface, on a side note. In more simple
terms this tells us that if we reduce the wind input by 10%, we harvest 30% less energy. The rotor has physical restraints in how fast it can turn
until it comes apart very violently (youtube)
. We can calculate that because of the 10/30%
reduction that wind power plants need at least 14m/s wind speed to gain it's peak output that it will keep due to oscillating the blades until the
wind reaches about 20-24m/s depending on the height and type of turbine. They will start to turn at very low efficiency at around 4m/s.
From the above we gain knowledge that the range of usable wind is very narrow. Here are some visuals
How they work:
The rotor is turning, either wires or magnets, and the turning motion of the magnetic field lines will induce a rate of change inside the different
copper windings. The rate of change in an magnetic field is what makes electrons want to chooch along, when they are influenced by it. In very easy
terms, we can imagine an archimedes screw, where the alternating magnetic field lines are the spiral screw, and the electrons are examplified by
water. The screw / field turns, the electrons move along.
For those that didn't step out mentally yet, I know it's a lot of input, if you haven't looked into this at all yet. Consider this: A coil gun uses
the same principle but in reverse. Instead of moving something magnetic through coils inducing a current, we introduce small current bursts along the
projectiles trajectory. With coils that will in turn induce a current inside the projectile that in turn builds up a magnetic field that is attracted
to the coil in front until it passes it half way through. It gains velocity, rinse and repeat until the projectile leaves the muzzle.
We learned before that the relationship between the power output kW and the anual possible amount of power to harvest is kWh. For wind power plants in
the 10MW range, depending on the location we know from datasets in Germany, that it's in between 1456kWh/kWp and 2200kWh/kWp. Therefor, a typical wind
turbine can do about 1456h - 2200h yearly.
The lifetime of these wind turbines is about 20 years under such conditions.
This is currently the best we can come up with, there are better efficiencies each year but we have to consider that the already installed ones are
10-20 years old. The first wind power plants are already being decomissioned that were built around year 2000. That's why most of my data is from
2010, to present and somehow normalize it to real conditions, without considering the distribution though. It will do for us.
Recycling these turbines is not as easy as recycling PV arrays, but they have way more energy density, in terms of material usage than PV-modules. For
PV-modules surface area for 10MW using current module technology: 400Wp/1.6 square meters is 250Wp per square meter. This means, flat mounted, we need
about 40.000 square meters. But this is not reality. For maximum output we need to tilt the modules according to our position relative to the sun. You
might now think this would reduce the surface but consider the shadow we now get. Depending on the location we need to double the amount of surface
needed. This link will give you an idea, it shows what I just explained perfect:
Scandia 3.3 MW Ground-Mount Solar
Wind turbines should be spaced about 3-5 (4) times the diameter of the rotor next to each other.
For stacking them behind each other in a row, we need 6-10(8) times the diameter. Because they span into both directions from the core, for turbines
not located at the border of the wind park...
Aproximating this would mean for a 10MW wind turbine with a rotor diameter of 145m, we can easy calculate this in our head:
(4/2)*145m * (8/2)*145m = A
2*145m * 4*145m = A
290m * 580m = A
2.9*5.8 = A/(100*100)
16,82 = A/10.000 | *10.000
This is about double the surface area that PV-arrays need but the difference is, less material, less equipment to fail than in solar arrays. If we use
the above data and include the inverters that are available in the 1MW range, we would have over 10.000 electric components that could be damaged or
fail. Some failures take a whole array offline, some take a MW offline, depending on if an inverter failed, or a module.
On the contrary, if the wind turbine fails, it's zero output, while the solar array can always count on reduncancy because the arrays are in parallel
As explained before, hydrogen, because of the atom size, will easy diffuse through most materials. About ten years ago, we found a highly porous type
. It can store hydrogen in two ways, at relative low temparature
with a pore-volume of about 33%. These pores are big enough to shelter little gaseous molecules like N, or H.
Image credits, unmodified: DynaBlast
The valence electrons, according to generally accepted atom model that Niels Bohr came up with, are zipping around the atom core on the most outer
shell. These valence electrons interact with the cores of the atoms involved. Long story short, these valence electrons like to bind together. In this
case, they bind with the valence electrons from the Magnesiumbordhydrid, if circumstances allow.
Under pressure, the material contracts and folds in itself and gains 80% more density than before. While it folds, additionally it shrinks about 44%
There are similar materials where we can manipulate these bonding and absorbing properties, effectively turning it into a relative safe, diffusion
optimized storage material.
That's good enough right? No. If we want to maximize the efficiency on all parts of the production and delivery chain, we need something different.
Something that we, the civil public, are not allowed to have because of weapons of mass destruction.
The images I used are all free to use, when credited with Author and License, to be found clicking the link). Should there be any problem in using
them though, I will remove them and make my own.
Okay enough technical stuff.
Part two will include my thoughts about the current political situation and will follow in the next few days.