I.

U.S. Energy Administration statistics show that the U.S. energy consumption from 1650 to 2009 had an average annual growth rate of 2.9%.

[Image description] U.S. energy consumption, with the red line indicating an average annual growth rate of 2.9%.

You might think, 2.9% is not a very high growth rate. To some extent, that's true. Over the seventy years from 1949 to 2019, China's electricity consumption increased 1,978 times, which translates to an annual growth rate of 11.5%.

So it seems, a 2.9% growth rate is relatively mild.

However, a physicist from the University of California doesn't see it that way. He raised a question that has never been asked: If humans continue to produce and consume energy at this rate, what will happen?

Next, I will introduceHis calculation results. I don't know if his calculation is correct, but I think his reasoning is right.

He later wrote a book called"Energy and Human Ambitions on a Finite Planet" (Energy and Human Ambitions on a Finite Planet), which is available for free download online. The book contains detailed calculations, and those interested can check it out.

II.

He first assumed that the global energy growth rate is 2.3% per year. This makes the calculations easier, and this rate is exactly equal to a tenfold increase every century.

At this rate, in the year 2122, a hundred years later, the world's energy will be ten times what it is today; in the year 2222, two hundred years later, it will be one hundred times what it is today.

So, the question arises.How can humans increase energy to 100 times today's level within two hundred years?

Fossil energy is impossible, while solar energy is feasible. According to Wikipedia, the solar energy reaching Earth in one hour is more than the energy humans consume in a year.

If we make full use of solar energy, it is indeed possible to increase energy to 100 times today's level. However, in that case, every inch of land on Earth would need to be covered with solar panels.

Calculations show that maintaining a 2.3% growth rate for 400 years would require covering all of Earth's surface (including the oceans) with solar panels; maintaining it for 1350 years would mean human energy needs would equal the entire sun's energy; and maintaining it for 2500 years would mean human energy needs would equal the entire galaxy's energy.

[Image description] A 2.3% energy growth rate would lead to humans needing the entire galaxy's energy in over two thousand years.

This is obviously impossible. However, even without considering the distant future, just maintaining a 2.3% energy growth rate in the coming decades, humans will face a serious problem: heat dissipation.

III.

Physics tells us that as long as energy does work, heat must be generated.

Humans consume more and more energy, inevitably producing more heat, and the Earth's heat dissipation problem becomes increasingly severe.

The Earth primarily radiates heat into space through infrared radiation. However, the increase in greenhouse gases obstructs infrared radiation from leaving the atmosphere, trapping more and more heat on the Earth's surface, leading to global warming.

The more heat humans generate, the more heat remains on the Earth's surface, and greenhouse gases exacerbate this problem. Therefore, the extent of global warming is directly correlated with human energy consumption.

In 2020, the average global temperature was approximately 14.9°C. If the energy growth rate remains at 2.3%, in 350 years, the global average temperature will reach body temperature at 37°C, in 450 years it will reach the boiling point of water at 100°C, in 750 years it will reach the melting point of steel at 1500°C, and in 950 years it will reach the surface temperature of the sun at 5500°C.

[Image Description] If the energy growth rate remains at 2.3%, within a thousand years, surface temperatures will be as high as the surface of the sun.

This is entirely reasonable: if humans generate energy on Earth comparable to that of the sun, then the surface of the Earth would certainly have the same temperature as the sun's surface, let alone that the Earth is much smaller than the sun.

Four,

United Nations It is estimated that if the global average temperature rises by 4.5 degrees, half of the species will face the risk of extinction. If temperatures continue to rise, humans may also face extinction.

Therefore, if the energy growth rate of 2.3% remains for another one or two hundred years, Earth's heat dissipation problem will pose a survival crisis for humans.

Everyone can think this way: the current energy consumption of humans has already caused summer temperatures to rise to 40 degrees. If a hundred years later, energy consumption becomes ten times the current level, how high would the temperature be then?

The conclusion is clearly that energy cannot maintain a long-term growth rate of 2.3%. According to the current energy growth rate, the time left for humans is already very limited, it is likely that within a hundred years, humans will have to stop energy growth to alleviate the Earth's cooling problem.

Energy growth is strongly correlated with economic growth. Therefore, within a hundred years, human economic growth may also stagnate.

The best-case scenario is that by then, the world's population has already started to decline, so there would be no need for so much energy, and living standards would not decline significantly.

Five,

ideal is ideal, but the reality is that the world currently has an urgent demand for energy, and there are signs of acceleration.

Harvard University this year hasA studyto estimate how many air conditioners are still needed worldwide.

They found that 2.8 billion people live in the hottest regions of the world, and as temperatures rise, all of them will need air conditioners. However, only about 8% of them currently have air conditioners in their homes, while the rest are eager to get them as soon as possible.

[Image description] Air conditioners are the most desired home appliances for Indians.

Harvard University estimates that by 2050, the proportion of people needing air conditioners will be 92% in Germany, 96% in the United States, and 99% in India and Indonesia.

The current penetration rate of air conditioners in the United States is 90%, so it only needs to install air conditioners for another 6% of the population. However, the penetration rates of air conditioners in India and Indonesia are currently 5% and 9% respectively, which means that air conditioners need to be installed for more than 90% of the population.

These two countries are populous nations. Indonesia has 270 million people, and India has 1.4 billion people. Providing air conditioners for everyone will require an astronomical amount of energy.

Therefore, in the coming decades, global energy will certainly grow rapidly to meet the demand for air conditioning. Governments will have to increase energy supply because air conditioning is no longer a luxury but a necessary device for survival, otherwise high temperatures could lead to casualties.

VI.

This is the severe situation humanity faces: increased energy leads to rising temperatures; rising temperatures, in turn, require more energy for cooling, creating a vicious cycle.

As mentioned above, humanity's period of energy growth may only last for the next century. How can human society, within such a short time, endure global warming while achieving economic transformation and reducing energy consumption, remains an uncertain and pessimistic path.

(End)