Please create an account to participate in the Slashdot moderation system

 



Forgot your password?
typodupeerror

Comment Re:Cooling? (Score 1) 87

It's a lot more complicated. Remember the solar panels to power the data center? They catch Sun light, so you need to add them to the surface of your data center. And to keep it at 300 K, you need twice the area to the other side to radiate off the heat. And those areas should not face each other, because they would then heat each other. It's a lot easier with convection, because then, the moving gas molecules transport away the heat.

Comment Re:Cooling? (Score 2) 87

You can calculate the amount of heat you can transfer via radiation. It's called Stefan-Boltzmann law. At a temperature of 300 K, you can radiate 460 Watts per square meter as a maximum. But from the Sun, you get 1370 Watts per square meter. That means that you have to have at least twice the area away from the Sun to keep temperatures at 300 K. A spherical body like the Earth would be at equilibrium at 279 K if it gets no other energy except direct Sun radiation.

Comment Re:Nuclear would have prevented this! (Score 1) 73

You can build nuclear if you want, But all I see right now is nuclear construction happening in China, and in China only. All new nuclear plants built in the west were to replace older ones or are upgrade of them.

Even France, which never had a problem with nuclear, basically stopped building them in the 1990ies, and the only new plant coming online since then is the Flamanville EPR. It was always easy for electrical companies to stop nuclear projects and blame the Left and regulations, when in fact, the projects simply became too expensive compared to the alternatives. It's similar to the turbine car from Chrysler, where environmental regulation were cited why it stopped, when in fact, turbines still suck in partial-load situations, which is what most cars are in most of the time.

I don't think nuclear will have a great future. It might exist for some niche applications, but in most cases, it's just fricking expensive.

Comment Re:"net-zero emissions by 2050" (Score 2) 73

Maybe it's not the CO2, but the methane from cow belches. Methane is a more potent greenhouse gas than CO2, although it breaks down more rapidly in the atmosphere.

While Methane is a more powerful greenhouse gas, it is also one which gets removed rather quickly from the atmosphere, because it gets destroyed by the sunlight and turned into water and Carbon dioxide. Carbon dioxide on the other hand is stable, and if not actively extracted from the atmosphere, will stay there indefinitely for billions of years.

Comment Re:By digital sovereignty. (Score 1) 25

Let's put it like this.
  • Natural Gas accounts for 12% of Germany's electricity generation in 2025
  • Wind accounts for 30% of Germany's electricty generation in 2025
  • Solar accounts for 19% of Germany's electricty generation in 2025
  • Biomass accounts for 8.5% of Germany's electricity generation in 2025
  • Lignite accounts for 16% of Germany's electricty generation in 2025
  • Hard coal accounts for 6% of Germany's electricity generation in 2025
  • Other sources (Coal Gas, Incinerator plants, Oil, Hydro) make up less than 8% of electricity generation in 2025

Now you can throw around buzzwords like deindustrialization, or you can look at the actual numbers.

Comment A Stanislaw Lem story (Score 3, Interesting) 42

This reminds me of a Stanislaw Lem SF story (I think published in the "Fables for Robots" series): The Trap of Gargancjan.

Two countries start an arms race by moving their whole military to AI, and then set their armies to fight each other. But when all the robots connect to each other to create the two AIs of cosmic scale, they don't fight, but greet each other, take each other's hand and walk through the flowers. Because Space at its essence is peaceful, and war is not a cosmic concept.

Comment Re:Extrapolation (Score 1) 179

I see your comment, and I know that the same error was made several times. There are numerous articles from the last couple of decades, where people point out that the exponential growth of Solar is unsustainable. Here we are in 2025, and the growth still is exponential (and has been since 1992). You have to bring up really good arguments why it should be slowing down anytime soon.

And no, I don't require every city to plaster its roofs with Solar. I just want to point out how much people underestimate the potential of Solar, because they totally underestimate the amount of energy the Sun actually provides.

Lets say, we are able to capture 20% of the Sunlight reaching the ground (actual numbers are more closely to 25%, and research solar cells reach 45%). About 70% of the Sun light is reflected by the Sun's atmosphere. In the temperate climate zone, Sun light hits the ground on average at an angle of about 45. Lets consider rainy days, and about 10% of the Sunlight will be ready for capture, of which we then capture 10%. With the Solar constant being about 1.4 kW, that means that each square meter Solar can capture 14 Watts. A person living in a city needs about 2000 kWh per year (which not only covers domestic use, but also powering the infrastructure), and with a square meter able to catch about 140 Wh per day, each person needs about 20 square meters of Solar to fully cover their energy needs. A city like Houston has a population density of 1600 inhabitants per square kilometer, which means that for each person, there are about 600 square meters of land area in Houston. Only 20 of them are needed to power the city.

Comment Re:Extrapolation (Score 1) 179

The estimates are very rough indeed. If you do the math for any city, you will find out that just the roofs in that city provide enough space for Solar to power the city. It's not that we will run out of space for Solar very soon.

And then, you are projecting linear growth for Solar and Wind, but the actual growth rates are exponential. Roughly every three years, the amount of Solar and Wind installed is doubling - doing so for the last 15 years. In 2027, the World will install 1400 GWp, in 2030, it will be 2800 GWp. Taking your 25% estimate (it's actually more like 17%, but that moves it just into the next year), we will install as much Solar in 2045 year as the total fossil energy output today.

Slashdot Top Deals

Where it is a duty to worship the sun it is pretty sure to be a crime to examine the laws of heat. -- Christopher Morley

Working...