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Visualizing CO2

NASA has released a video called Model Behavior: Visualizing Global CO2 that shows how carbon dioxide is emitted from areas of the Earth and combines with winds in the atmosphere. This is based on data collected from their satellites.

The video clearly shows that much of the CO2 released is caused by human activity.

Watch this video on your largest computer screen and make sure your sound is on and turned up.

Watch the Video

Weather Extremes and Renewables

by Ed Sawicki

I was once caught in a hailstorm while driving and pulled to the side of the road next to a tree whose branches softened the blow of the hail pounding my car. I put my seat back and moved my body away from the windows as much as possible. Fortunately, the windows held.

When it was over, I examined the 1 to 2-inch-diameter hail stones. They were solid ice. A Google search showed that the likely speed of these stones was between 40 and 72 miles per hour. More recently, there have been news reports of 4-inch-diameter hail whose terminal velocity is 125 miles per hour. These carry a kinetic energy of 740 Joules. For comparison, a fired 9‑millimeter bullet carries about 500 Joules.

What impact would hail have on solar farms, whose panels are vulnerable? The photo above shows the result of a solar farm in Texas after a hail storm.

Here's a video of a large solar farm with hundreds or thousands of panels destroyed by hail.

Here's another video of Texas residents who have contamination concerns after solar panels were damaged.

What about wind turbines? They're vulnerable to severe storms as well. This photo is a turbine whose blades were damaged by extremely high winds during a storm. Other turbines caught fire and collapsed.

What does a power company do when they lose a solar or wind farm? They burn more coal, oil, or gas to make up the difference. That is, if they still have that capacity after switching over to renewables.

We're doing little about climate change and expect severe weather to get worse and more frequent. Our renewable energy resources are vulnerable.

What's the solution? Nuclear energy, using modern, safe reactors.

Wind Turbine Carbon Footprint

Wind turbines may produce green energy but there's nothing green about manufacturing and installing them. Let's start with the concrete bases for on-shore wind turbines. The first photo shows the steel cage that will reinforce the concrete. This steel is called rebar (short for reinforcing bar) and typically weights 75 tons.

Sometimes the ground (the soil) is such that the concrete base must rest on concrete pillars that extend into the ground by a dozen meters. Concrete pillars are also used for offshore wind turbines.

There will be about 700 cubic meters (24,720 cubic feet) or 915 yards of cement poured into this cage, which will weigh several thousand tons. The cement is delivered to the site by ready-mix cement trucks—typically four or more trucks are used to keep the cement coming once the pour begins. These trucks carry up to 10 yards of cement, so it will take 92 trips between the cement plant and the wind turbine site. The trucks' average gas mileage is 3 miles per gallon.

For a wind farm where there will be many turbines, a portable cement batching plant will be setup nearby. So, the ready-mix trucks do not have to travel a great distance. However, the ingredients for making cement (aggregate, cement, and water) must be trucked to the site, and the distance could be great. This plant expends energy when it batches the concrete. Generally, a cubic meter of concrete requires 2,775 MJ (megajoules) of energy and the byproduct is carbon dioxide.

It's common for the cement to be placed in the hopper of a concrete pump that can pump the cement via a hose or boom to distances that the ready-mix cement truck chutes cannot reach. This pump too takes energy and releases carbon dioxide into the atmosphere.

Wind turbine blades are transported by special trucks designed to handle the long blades. The photo shows two disconnected parts to the truck, with each part having a driver who steers. The blades are manufactured in only a few locations within the United States, so chances are good that you'll see them along the highways. They must be moved over long distances.

Here's a photo of a blade being transported through Hawick in Scotland on a truck that can elevate the blade to make it easier to navigate narrow and winding streets. The blade can be lowered (the angle of elevation can be lowered) to allow passing under power lines.

Heavy equipment, such as tall cranes need to be brought to the site to install the blades. The photo shows two cranes but many installations use only one crane.

These heavy cranes that weigh between 80 and 165 tons need to be trucked to the site.

Each turbine requires three blades. Each blade generally has a lifetime of 20 to 25 years, so they must be replaced. This requires trucks to transport the new blades and remove the old blades. It requires cranes to remove the old blades and install the new ones.

The old blades can be cut into smaller pieces, thus making it easier to transport the pieces away from the site. You can think of these used blades as waste.

The U.S. Wind Turbine Database currently contains data on 74,511 turbines in the U.S. Do the math:

74511 turbines x 3 blades = 223,533 blades

Each of these 223,533 blades needs to be replaced and disposed of every 20 to 25 years.

What do we do with all this non-recyclable waste?

The wind turbine gearboxes and generators that are located in the nacelle have an average lifetime of about 20-30 years. But failures of these occur sometimes and heavy equipment is usually needed to make the repair by swapping them out.

So, yes, wind turbines generate green energy, but it takes a while to make up for the environmental costs of manufacturing and installing them. It's estimated that the first two years of the turbine's lifetime is spent paying for those environmental costs. There are industry estimates that put the payback at less than a year but these are likely not considering all the environmental impact.

You can say that wind turbines produce green power two years after they're installed and not be wrong, though some will say you are.

Sources

Want to know how a wind turbine foundation is made? (1 minute)

The Making of a Wind Turbine (50 minutes)

Energy consumption in production of concrete

NREL determines how to transport wind-turbine blades

Moment giant wind turbine blade carried through Hawick

Comparing Wind and Nuclear

Let's compare a wind farm and a single nuclear reactor. In the United States, the most popular wind turbine is currently the General Electric 1.5 MW. Since there have been few installations of new nuclear reactors in the U.S. in decades, and none represent the state-of-the-art, we'll use an example of a relatively small modular reactor (SMR) that uses molten salt.

A molten-salt reactor (MSR) combines the nuclear fuel and coolant in a low-pressure, high-temperature vessel. This is the opposite of traditional water-cooled reactors that are low-temperature, high pressure. That high-pressure required a thick concrete containment chamber. MSR reactors use far less concrete if concrete is used at at all. But you'd still want a building made of concrete to enclose it.

Let's assume a small 300 megawatt (MW) reactor. How many General Electric 1.5 MW turbines does it take to build a 300 MW wind farm?

If the wind could be counted on to be there 100% of the time, the math would be simple:

300 / 1.5 = 200 turbines

But the wind is likely not there all the time. The GE turbine must have a minimum of a 8 to 9 mph wind to operate. It must stop operating if the wind exceeds 45 to 55 mph. The nuclear reactor has no wind limitations.

How will we solve the wind problem? We could increase the number of turbines and rely on batteries to store excess energy for the times when the wind isn't blowing or rely on other power sources, such as natural gas, to get us through lean times. This complicates our comparison. Let's bump up the number of turbines to 300 and assume batteries will be used.

How much concrete for 300 turbine bases?

300 turbines X 915 yards of cement = 274,500 yards of cement or 27,450 Ready-Mix trips.

It's difficult to say exactly how much cement is needed for the reactor building, utility building, access road, and miscellaneous other structures. Let's say 300 yards or 30 Ready-Mix trips.

With 300 turbines, 900 blades need to be installed requiring heavy equipment (cranes) and transport of those blades from long distances.

What about those batteries needed to store excess electricity because we can't count on the wind always being there? Their lifespan depends on the technology used. It can range from 5 to 15 years, with improvements expected in the future. Fortunately, heavy equipment like cranes are not needed to install or maintain them.

AI and the Environment

Artificial Intelligence is going to place a huge strain on the environment. Consider this sentence from a recent article:

“Along with its partners CoreWeave and NVIDIA, Inflection AI is building the largest AI cluster in the world comprising 22,000 NVIDIA H100 Tensor Core GPUs.”

The NVIDIA H100 Tensor Core GPU requires 700 watts of peak power. The total peak power for a cluster of 22,000 of them is 15.4 megawatts! And that doesn't include the power used by other circuitry and cooling systems. Lets round it up to only 20 megawatts for the cluster, which can power approximately 20,000 homes.

How many AI clusters will there be in the world in time? Even at only 100, that's 2,000 megawatts (or 2 gigawatts) that can power 2,000,000 (2 million) homes. It's more likely it will be ten times that number.

What must we do to meet this demand without placing more toxic waste into the atmosphere and worsening climate change? The best bet is modern nuclear power.