Why is agricultural productivity always lower than industrial productivity?

The energy conversion and utilization efficiency in industrial production is much higher than that in agriculture. For example, under rated load, the efficiency of type I asynchronous motor is 75%~92%, that of ordinary internal combustion engine is 40%~ 60%, and even the steam engine in the 20th century can reach more than 20%. This makes it possible to find dense and unit input energy through long-distance transportation, thus greatly improving the output per unit area. The early newcomen atmospheric steam engine had to use coal locally because of its low efficiency (less than 3%), but it could only be used in coal mines. Textile mills far away from coal mines have to wait for Watt steam engines with efficiency close to 10%, otherwise they will go bankrupt just because of the coal transportation cost. Similarly, due to the low utilization rate of light energy, large-scale agricultural production must be? Local consumption? Otherwise, it will go bankrupt because of the cost of artificial lighting.

Because agriculture is ultimately the use of light energy, the natural light energy per unit area is limited, and the efficiency of natural photosynthesis is too low. First of all, the ratio of energy output to energy input in agricultural production cannot be improved. Second, the cost of artificial lighting is extremely high, which determines that the energy input per unit area cannot be improved. These two? Can't improve? It is decided that agriculture can not improve the theoretical maximum yield (value) by investing more capital, technology and personnel/unit area; Agricultural productivity can not exceed the upper limit, and because of the low efficiency of natural photosynthesis, the upper limit is very low, only 50 thousand yuan/mu. On the other hand, in the process of industrial production, the efficiency of energy conversion and utilization is much higher than that of agriculture, so the concentrated input of energy (capital, technology and personnel) per unit area can greatly improve the output; Its upper limit is much higher than that of agriculture. Not to mention high-tech industries such as chip factories, it is not difficult for textile mills to achieve an output value of one million yuan/mu. Therefore, at the current level of science and technology, agricultural productivity will definitely be lower than industrial productivity. Only in the future will the productivity of factory farming increase? Extremely cheap energy, artificial fill light and high light efficiency? To compete with some industries, but maybe not then? Agriculture? .