Where Did Central Heating Come From? One Article to Understand the Origins and Evolution of Heat Networks
Ancient humans learned to use fire, and from then on humanity developed into Homo sapiens, completely separating itself from the animal kingdom. This shows how important the utilization of heat energy is to human society. In early human societies, the use of fire and heat was an individual act.
After capitalism emerged in the course of social development, the division of labor in society gradually became more refined. Intensive operation became a social option. It was probably in the 19th century that socially shared pipelines for centralized steam transmission appeared in the United States—likely the prototype of the heat network. Because fuel prices were extremely low at the time, the centralized heating industry could not turn a profit for a long time. Compared with independent heat extraction, centralized heating is unquestionably more advanced and more economical. Eventually, centralized heating became an industry and flourished.
When it comes to centralized heating, there are naturally heat sources and users. Pipelines connect the heat source with the users, and the efficient mode of operation is naturally: one heat source serving many users. The pipelines connecting the heat source and numerous heat users form a pipe network.
Users have diverse purposes for using heat. Household users need domestic hot water; residents in cold regions need heat in winter to keep their homes warm; residents in hot summer regions need cold water to lower indoor temperatures; hospitals need cold water, hot water, and high-temperature steam for disinfection in all four seasons; manufacturing plants such as food and textile factories require water steam at 100°C–150°C in their production processes. Chemical plants may require steam at even higher pressure and temperature. These diverse social needs have given rise to heat pipe networks with different functions in the industry: air-conditioning pipe networks for centralized cooling, thermal pipe networks for centralized heating, and centralized steam-supply pipe networks for production needs. The LNG industry is too specialized and niche, so it is excluded from our discussion.
As a heat source (including cold source), it may be a district boiler room or a centralized refrigeration station. Among these, thermal power plants have been the most influential heat-source plants in recent decades. The cascaded utilization of heat energy has greatly improved energy efficiency, making them the mainstream heat-source plants for centralized heating.
Extremes breed reversal. The intensive consumption of fossil energy has placed a burden upon the Earth that it cannot bear. Changes in the heat sources for centralized heating are therefore inevitable. Correspondingly, this will inevitably exert a major influence on heat network technology. To adapt to a changing world, practitioners in the heat network industry must shoulder the social responsibility that concerns the destiny of all humanity. Let us join hands to protect the common home of humankind.