Question
How can we break the current limit of energy conversion efficiencies?
How can we break the current limit of energy conversion efficiencies?
Give up fantasy
Various forms of perpetual motion machine have long been abandoned by science and should no longer waste time discussing them. Fortunately, this is a problem in engineering materials. According to the thermodynamic law , the highest efficiency between the two temperature sources is Carnot cycle efficiency 1-Tlow/Thigh. Here it is better to use "how to break through the limits of..." rather than "how to use energy scientifically".
Among the energy conversion methods used by humans, all of them must satisfy the laws of thermodynamics. Let’s briefly list them first (rough data).
Coal-Electricity: ~40% ( Steam Turbine )
Natural Gas-Electricity: ~60 (Gas-Steam Combined Cycle)
Water-Electricity: ~80% ( Water Turbine )
Wind-Electricity: ~45% ( Wind turbine , Bates limit value 59.3%)
Solar energy: ~25% (silicon photovoltaic conversion method)
Nuclear energy: ~33% ( nuclear fission , pressurized water reactor)
A brief analysis:
- Traditional Thermal power generation
coal-natural gas are all forms of thermal power generation. Natural gas power generation can be highly efficient because the "taste" of energy is improved through impeller machinery.
- Hydropower and wind power
are the conversion of kinetic energy to electrical energy, rather than the conversion of internal energy to kinetic energy. There is no need to apply the concept of Carnot cycle . Because internal energy is the energy of disordered thermal motion, water-wind is the orderly (speed direction fixed) translational energy. Therefore, the efficiency of hydropower can be very high, but the efficiency of wind-power is not high because of the contradiction in the circulation of gas through the fan.
- Solar energy
Photovoltaics directly use the photo-electric effect to generate current. Due to the selectivity of the material, the efficiency is low.
- Nuclear power
Pressurized water reactors are close to coal power, in fact, this is because steam turbines are used in the end, and the former has greater losses. Let’s take a small inventory of
.
improvements: Even a little
steam turbines need to improve the temperature resistance of the furnace that produces steam, so they need improvements in material science .
Gas turbine can also improve the working parameters (in the end it generally falls on the material)
and so on.
combined innovation: giving high-taste help
is like cooking, cross-reorganize it for some inspiration.
Let’s give an example: For example, you see that the low photovoltaic efficiency of solar energy is due to the selectivity of photovoltaic materials. Then the light is converted into heat and then used by other thermal machinery. The common saying of
is: use solar energy to heat the water and then send it to the boiler. It will only be 25% to 40%. Various conditions need to be considered in the actual application of
, but the idea in the above example is correct: low-level people ask high-level people for help. People with low levels of skills are incompetent themselves, so they work as secretaries for people with high abilities. And then in the final calculation, the contribution is greater than that of most people. Think about it, everyone. When
wrote this, I found that it was too far off topic, and this topic overlapped with energy issues.
pull back a little.
material
Among the improvements mentioned earlier, the key is the material. The periodic table of elements is inherently limited, and the earth, an ordinary planet, cannot preserve too many rare high-performance materials.
For example, the metal rhenium in turbine blades. Anyone who doesn’t understand the game behind it is not a qualified military fan. These rare materials and their alloy technologies could change the status quo of a planet's energy use.
Maybe we can look forward to the gift of the universe and catch a pure rhenium asteroid, which can be considered a breakthrough.
God: It is obviously due to the lack of human ability, but it is blamed for the resource limitation of the technology tree.
Yunzhi Entropy: Just watch human beings raise their material limits several times.
God: I don’t have anything other than the periodic table of elements.
Yunzhi Entropy: Not so much, please try your best
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-