Nuclear energy is more expensive than renewables, CSIRO report finds

Yes, there is a lot missing in this chart - exports (what source and where it's going), electricity from other fuels, imports(?). Plus they show little more than half a day.

The green web sites seem to be too tightly focused on what they're proud of. Also, they skipped almost half the day! I usually skip these sites.

A lot of energy during daylight hours is now a problem!!


I've been wondering if China's high tech distribution lines, if built here, could export solar a few time zones east, changing the time of day issue at least slightly. It seems similar to what China is doing, with its western desert energy projects.

 

If you go to the CAISO website you can see the full details of the day. The X poster is the one that only clipped part of the day because that's all the data that was available at that time. Still I have issues with the way CAISO is presenting the data. Because it's so misleading that it's hard not to think it's intentional.

 

If you go to this page
https://www.caiso.com/todaysoutlook/pages/supply.html

and change the date to April 14th..

You can see that during the morning the energy is supplied primarily by natural gas and imports. California has to buy energy from out of state in the morning and the evening. In fact imports alone greatly exceed renewables at the end and beginning of the day.

This huge amount of import energy is due to the fact that California suppliers can't afford to keep baseline generators online if they are forced to export during the middle of the day during peak solar.

 

Well analyzed and said.

 

Ohm's law disagrees. The longer your distribution line, the more resistance it possess, the more voltage you drop across that distance.

Since we're talking about AC you also have to deal with the reactance of the transmission infrastructure. Large transmission lines have capacitance and inductance. These two properties create an LC tank that can (& does) introduce lots of headaches into AC circuits.

Besides that, the energy lost from long transmission lines is energy that is lost mostly in the form of heat, which makes it yet another strange way to save the Earth from global warming.

 

True.

The transmission technology in China is reputed to have less resistance, and thus be less lossy per unit distance.

Also, I think they are using DC, and I think it is at super high voltage.


I'd be shocked if the heat from transmission lines could make a detectable difference in Earths temperature. Plus, greater efficiency in electrical transmission isn't just for climate change.

 

Resistivity of copper and aluminum does not change with technology....

The only thing that drops it is cross sectional area. Thicker cables = way more expensive and a larger impact on environmental resources.

Also on the temperature front...

We're collecting energy from the sun and conserving it to the Earth. The more we conserve to the Earth the hotter the Earth gets. Let's not have to conserve more of it to the Earth so that we can waste it sending it half way around the Earth...

 

As you know, electricity in high tension lines doesn't just travel through the metal.

Collecting solar energy saves heating. Subsequent releasing of that energy isn't going to be greater than what was collected.

 

No different to the transmission of carbon based electricity generation. You can use the existing transmission system

The captured sun energy is captured by Earth anyway regardless if by solar panels or not

 

It's very different. The proposal for long distance transmission of solar energy was to solve the issue with the disparity between demand and production. They want to send solar energy to places where it's dark. This is not an issue with traditional generators because they have the ability to operate 24/7.

That's not true, in point of fact. The Earth's albedo reflects approximately 70% of solar radiation. Solar panels capture 90% of it and convert 20% of it into electricity. The rest is converted to heat. Then, when the electricity is used it is also converted back into heat.

 

Not sure what you attempting to communicate here. Charge travels through the field. Electrons vibrate in the conductor.

What was collected would have been radiated into space, harmlessly. What we radiate after use is at different wavelengths that are captured by the same process "going green" is attempting to reduce. Don't get me wrong, I'm not against solar. But don't be fooled by the idea that spending trillions of dollars on completely retooling our energy system will somehow save the planet from some kind of environmental disaster. We're just trading one effect for another, and quite honestly we have little idea what that looks like over a longer term.

AC is used because it's easy to transform. DC is used because impedance is not a factor. The reason our grid isn't DC (most of our electronics are DC) is that DC is much more difficult to transform from high voltages & currents to usable safe voltages and currents. Ohm's law tells us that V=IR. So given a known quantity of resistance of our transmission lines, as our voltages increase the current carried through them must decrease for a given amount of power usage. It's the current that heats up the wire and increases its resistance. What's great about AC is that we can send it through a transformer. Transformers use mutual inductance to very efficiently convert high voltage / low current into low voltage / high current to power our devices. This is much safer for humans to interact with.

In DC this is not so easy. Mutual induction requires a growing and shrinking magnetic field, but the magnetic field DC generates is static. The act of converting DC into safe power loses much more energy at that point of conversion. They use it for very long distances because impedance causes a tipping point between the efficiency of AC vs DC over long distances. But that doesn't mean there still isn't a massive amount of energy lost in both systems of transmission.

Think about it this way. You need food for your body. This will be the energy in my analogy. Your favorite restaurant only serves lunch, but there's one in every time zone. Is there any practical way for you to use your body's energy to efficiently eat dinner at your favorite restaurant?

This is the general problem of transporting energy. You have to use lots of energy to do it.

 

Very little of the sun's energy is reflected from the ground back into space. Most is absorbed by the atmosphere. The placement of solar panels has an insignificant effect on total reflected radiation. That 70% is only relevant if the whole surface area was covered in solar panels and that 70% figure is how much is absorbed by the atmosphere, not reflected back into space

 

An AC sine wave is actually a representation of the voltage produced in a coil of wire as the coil rotates 360 degrees through a magnetic field. When the wire cuts the flux from left to right the current flows in one direction and this assigns a sign to the voltage. As the wire completes 180 degrees it cuts the flux from right to left. This flips the sign of the voltage to the opposite and current flows in the opposite direction. The electrons in the wire actually move very little. They just push back and forth on each other through the electric field. The result is an analog waveform that's in phase with the speed of the rotation of the coil of wire. This waveform can easily be converted into direct current using diodes to "detour" the negative half of the wave back in the positive direction. This is called rectification. The purpose of the power supply in your computer is to accomplish this process. The single phase 120 (it's actually half of a phase) is stepped down to lower voltages with a transformer, and the transformer's output is rectified with a bridge & some smoothing caps to produce your DC signal, and then resistors and zener diodes are used to produce your +12v, -12v, 5v, 3.3v etc..

Doing the opposite is much more complex. Causing a DC current to reverse at a specific frequency with an analog waveform is impossible to do digitally. The only analog way to do it is to use the energy in a DC motor connected to an AC generator. Lots of energy lost in this type of inverter. The inverters you have connected to your solar panels are digital. They create a waveform that looks like this:



The inverters that are used in HVDC are far more complex than the small inverters on your panels, but the signal itself isn't much more pretty. Those kinds of waveforms suck in power supplies that are designed to convert analog signals into DC. That interferes with our ability to rapidly perform digital logic. Slower computing...

 

The Earth's albedo isn't uniform. Deserts, for example, actually have a higher albedo than rainforests. 70 is an average that is greatly affected by small shifts in the tails of the distribution.

This makes no sense to me at all. The rainforest, for example, has a low albedo. This is because photosynthesizing plants are converting that solar energy into sugar, basically sequestering that energy in chemical bonds. The heat of which is only released when we burn them. The panels on the other hand are directly converting the majority of that light into heat. So you could put a bunch of panels in the rainforest and not change the albedo significantly, but you do change the type of energy present at that location.[/quote]

 

Golly, who could have predicted Australians would so openly tie themselves to the Chinese supply chain then.... Just another example of folks who a) don't know the options and limiting themselves to pretty inefficient solutions to counterweight solutions from China/(Solar/wind) and assume that no one would notice just how deeply in the tank with China Australian politicians have become.

 

My understanding is that the global average albedo reflects about 30% of the sun's radiation back into space. This changes materially as clouds form, most of which reflect sun rays and add to the albedo. or decrease it when the clouds go away. The atmosphere itself absorbs very little sun radiation (as opposed to the less energetic infrared radiation emitted by the earth) with a noticeable amount (but small percentage wise) by oxygen and ozone in the upper atmosphere mostly, IIRC. in the ultraviolet wavelengths.

 

[/QUOTE]Super posts but, if I may, it seems you have albedo and absorption percentages turned around. The average albedo is around 30%, not 70%

 

Super posts but, if I may, it seems you have albedo and absorption percentages turned around. The average albedo is around 30%, not 70%[/QUOTE]


You may be correct. I don't think it changes the point, however.

 

What percentage of the Earth's surface is covered by solar panels? Using that percentage please explain how it has any significance of effecting reflected energy back into space

 

You may be correct. I don't think it changes the point, however.[/QUOTE]No, it doesn't.

 

Hell, go back two decades, and that is exactly what ENRON was exploiting.

I was still living in LA during that debacle, and it was a freaking nightmare. Blackouts at almost any time, sometimes even having to leave work early because after an hour even big companies like Hughes Aerospace would simply shut down without power. And that is exactly how it all was happening. California does not produce enough power in state, so has to import a lot of it. And a lot of power projects in other states were specifically made to sell power to California (but without a lot of the expense and regulation nightmares that California requires).

That entire debacle is that Enron was a "middle man", and realized that by interrupting the flow at certain times, they could hike up the rates to astronomical levels. So for months we had rolling blackouts as they raked in money. And even two decades later, with all the promises that "Green Energy" is the future, nothing has changed. They still import a large amount of their power, and the "green energy" can not even keep up with the growth in that state, let alone replace the demand already there.

Add to that the fact that they not only deny building of any new power plants, they are actually tearing down ones already in place (including hydro), and their actual production is decreasing.

 

Total yearly energy usage on Earth = 580 million terajoules

Total Earth Solar electric production = 1,306 billion kWh or only 4701.6 terajoules.

The percentage of Earth's total energy use that is supplied by solar is equally as insignificant. .0008%? The goal is to significantly increase that percentage is it not?

 

Exploit / Servicing Same difference. If Enron didn't "exploit" the problem, how much energy would California have had to use?

 

Does not matter, because no matter how you cut it, California is not "self-sufficient" in a great many resources, including water and power.

They get on their high horse and try to pretend that they are, but never seem to mention they are dependent on outside resources that are not as "green". To me, it is all smoke and mirrors, with them trying to keep their people asleep. Because if they were absolutely serious about all of their power being "green", they would cut all of those power lines from other states that are run to the state in order to help provide their insane demands.

All Enron did was exploit the market, causing artificial shortages to increase the amount they could charge. But during that time there was an increasing push to allow new power plants, as it made many realize that the state was not able to produce enough power for their own needs. And instead of doing that, after a bit people fell back asleep. Stopped asking for new power plants and this "green energy" made them all forget it. And now the state imports more power than ever before.

If I remember correctly, in 2000-2001 when that was going on, the state imported about 20% of their power. Today, it is more like 30%. And over half of that power imported comes from natural gas plants and hydro dams. Two of the very sources they are trying to eliminate in that state.

The state produces 208,000 GHh, and imports 84,000 GWh. In other words, California imports on average each year as much power as the entire state of Arizona uses. It imports over three times the amount of power that Idaho uses. And unless they do something, this dependence on power from other states is only going to increase. They like to claim they are the "greenest state", but the reality is they are not.

To be honest, I have come to see California as something of a locust state. And one of the reasons I finally got out of there myself.

 

It's about economics, and why there are more and more solar roof panel systems and windfarms. And nuclear power is just a faded dream and just a short term unsustainable answer as the use of fossil fuels is phased out anyway.