How should we provide heating for people in the south?

As a southerner living in the north, I feel the difference between winter in the north and south very deeply.

Northerners in winter: It’s too cold outside, come inside and warm up.

Southerners in winter: It’s too cold inside, go outside to warm up.

The people in the north have steam heating, water heating and electric heating, but the people in the south have only strong will.

Should we provide central heating to people in the south?

How can we enable people in the south to live a happy life with heating?

Scientifically speaking, which areas should be heated?

In the 1950s, my country imitated the Soviet model and drew a heating demarcation line divided by the Qinling Mountains and the Huai River. Areas north of the demarcation line where the average temperature was below or equal to 5°C for more than 90 days were given priority for centralized heating, which laid the groundwork for the envy, jealousy and hatred of the people in the south 50 years later.

The most common complaint of people in the south is that although the temperature in the south is higher than in the north, the human body feels colder than in the north.

That's right, this feeling has a scientific basis. Whether a person is cold or not depends not only on the temperature, but also on humidity, wind speed, light radiation and other factors. Among them, humidity has a greater impact on people's perception of cold and warmth. For every 10% increase in humidity, the temperature felt by the human body will decrease by 1 degree Celsius.

The average humidity in cities in the middle and lower reaches of the Yangtze River in winter is about 70%. For example, the average temperature in Shanghai in January and February is 3-5 degrees, but the humidity can reach 60%. According to the above algorithm, the "human body temperature" in Shanghai is actually around 1 degree to -1 degree.

As a migrant worker who grew up in the Yangtze River Basin, I still remember my hands being covered with chilblains every winter during my teenage years. It was a horrible sight.

So, if we divide the heating areas according to the temperature felt by the human body, how should we divide them?

Some researchers have compiled data from 740 meteorological stations in China from 1971 to 2010, and used the indoor AT calculation formula in the perceived temperature model that integrates air temperature and humidity to evaluate the indoor perceived temperature.

(AT=-1.3+0.92×Ta+2.2×Pa (1) In the formula, AT represents the perceived temperature (°C), Ta represents the air temperature (°C), and Pa represents the actual water vapor (kPa))

According to the human body's sense of cold and heat, the perceived temperature can be divided into five levels from severe cold to comfortable (from severe cold to comfortable). When the perceived temperature is lower than 8°C, people will start to feel cold. If we set the perceived temperature below 8°C and the number of low temperature days exceeding 90 days as the dividing line for central heating, we can get four different levels of heating areas.

The area with the highest demand for heating is the largest, accounting for 77% of the country. In addition to the areas that have already implemented centralized heating, there is also a section extending southward from Jiangsu, Henan, and Shaanxi, as well as a large area in the northwest of Sichuan and Yunnan. Ding Zhen, who has become popular on the Internet in recent days, is in this area. Traditionally, people rely on burning cow dung for heating.

The second is the area with high heating demand, that is, the area where the number of days with perceived temperature below 8°C in winter is between 90 and 120 days, accounting for about 8% of the country's area. It is mainly located in the Yangtze River Basin, which happens to be the hot spot for discussion on whether centralized heating is needed.

The district heating based on the perceived temperature will increase the area of ​​the district heating by 21.1% compared to the current district heating area. In theory, these "southern regions" have a hot winter and cold summer climate and all need winter heating.

We have already analyzed above from physiological experience and climate data, why the Yangtze River Basin needs heating. Now we will tell you a cruel fact.

Without heating in the south, people will die

In October 2018, the British Medical Journal (BMJ) published a research report by Chinese scholars. Based on the statistics of 1.82 million non-accidental deaths in 272 cities in China, it was found that low and medium temperatures (-1.4-22.8℃) were most correlated with non-accidental deaths, reaching 10.49%.

The study also confirmed that the temperature-related mortality rate in areas with less heating is significantly higher than in areas with more heating.

In 2010, the Chinese Center for Disease Control and Prevention also published an article titled "The Impact of Temperature on Excess Mortality in Three Cities in my country". The article investigated Shenyang, Taiyuan and Shenzhen and found that as the temperature dropped, the number of deaths in Shenzhen, which had no heating, changed most dramatically, and was significantly higher than that in Shenyang and Taiyuan, which had heating.

Isn't Shenzhen a subtropical area? Why does the death rate increase due to low temperatures?

Yes, this is a very cruel reality. Cold weather can induce cardiovascular and respiratory diseases, leading to a significant increase in mortality. Not only in Shenzhen, but also in nearby Guangzhou, the mortality rate will increase by more than 10% in winter. Nanjing, located in the Yangtze River Basin and known as one of the three major furnaces, also has a peak death rate from December to January of the following year.

To sum up, the high winter mortality rate in the south is highly correlated with the cold. Moreover, there is a significant difference between heating and no heating. To put it more simply and crudely, without heating, people are more likely to die.

In addition, a survey of 24 cities in seven southern provinces showed that in most of the winter in the Yangtze River Basin, the indoor temperature was below the hygienic lower limit of 12°C, which means that most people would feel miserable in such an environment.

So, do you still think that requiring heating is just a pretentious thing for southerners?

In addition to the misunderstanding that the cold in the south is not a big deal, we often see several opinions against heating in the south.

For example, buildings in the south are not insulated, so heating energy consumption is high and not cost-effective. This view is generally based on the "Civil Building Energy Saving Design Standard". Buildings south of the Qinling Mountains and the Huaihe River focus more on heat protection, sunshade and ventilation to ensure coolness in summer, but not on keeping warm.

How about adding insulation?

An authoritative expert in the industry said at an industry conference that it is unnecessary to add insulation to buildings in the south. In the winter, it is not cold, so there is no need for insulation. In the summer, it will increase the difficulty of heat dissipation and energy consumption. Therefore, the insulation of buildings in the south is a mess.

At that time, I thought that this expert must be from the north, and when I checked, it turned out to be true. At this time, the southern scholars disagreed.

Tsinghua University, Tongji University and South China University of Technology jointly conducted a study on "The application of external wall insulation system under various climatic conditions". In the end, it was found that adding insulation layer to buildings can effectively reduce energy consumption, whether in Beijing, Shanghai or Guangzhou.

Therefore, it is not true that houses in the south cannot be heated because they are not insulated. The previous standards are outdated and it is the standards that should be revised.

Opposition experts also said that residents in the south are accustomed to opening windows for ventilation in winter, so central heating is not suitable.

This reason is too unethical. We southerners open windows because we don't have heating. It's just as cold inside and outside, or even warmer outside. Besides, burning fire to keep warm without opening windows will kill you. You said that we don't need heating because we like to open windows, but it's better to say that we like to bask in the sun outdoors.

The people in the north have been showing off the superiority of central heating in winter for so long, it is impossible to expect the people in the south not to be jealous.

In 2018, a National People's Congress representative from Hubei proposed that the Yangtze River Basin be included in the centralized heating area.

Hubei Daily also published a commentary article, pointing out that the need for heating in the Yangtze River Basin is not only necessary but also urgent. However, the national conditions were not good before, so the most urgent need was to take care of the north first. Now that people are richer and have higher living standards, they hope to have heating in winter, which is natural and within their ability.

So, how can we provide heating in the south?

Central heating first requires a centralized heat source. For example, a boiler can provide heating for a small area such as a community or school. The cogeneration of heat and power from a thermal power plant and industrial waste heat can provide heating for a larger area through a pipeline network.

With this system, you can enjoy the warmth of spring in winter as long as you connect to the heating pipeline.

In recent years, some cities such as Wuhan, Hefei and Changsha, which are not located north of the traditional heating line, have also used thermal power plants for local central heating. Some new residential areas in Guizhou have begun to connect to geothermal heating.

However, it is still very difficult to popularize centralized heating in the south.

Let’s look at Beijing.

To provide heating for Beijing's main urban area, there are a total of six thermal power plants, coordinated with twelve peak-shaving boilers, which constitute the backbone of heating for Beijing's main urban area.

In order to provide heating for the entire Beijing, more than 60,000 kilometers of heating pipelines and 3,406 boilers scattered in various communities and units are needed. For the southern region, which lacks corresponding planning and construction, these cannot be built overnight.

During the winter peak, Beijing burns 100 million cubic meters of natural gas every day, which is equivalent to one-third of the national natural gas consumption and one-thousandth of the natural gas production. In other words, if there are more megacities like Beijing that require universal heating, China's energy supply may not be able to cope.

In addition to the huge infrastructure and energy consumption, Beijing's fiscal revenue also has to subsidize heating by 3 billion yuan every year, which is also a heavy burden on the public expenditure of many cities.

Therefore, students in the south will have to rely on themselves for winter heating for quite a long time in the future. The good news is that a survey by Tsinghua University shows that air conditioning heating, which is commonly used in the south, is only turned on when needed, which consumes less coal. In recent years, various carbon crystal floor heating, electric heaters, and household wall-mounted boilers have become more and more popular, and their prices are getting lower and lower, providing a solution for decentralized heating in the south.

Having said that, do you think this video will end without any trouble?

no.

When our southern friends are jealous of the heating in the north, they are actually jealous of the northern cities.

Rural residents in the north don't talk about the north where "there is heating". Just as northerners ignore how cold the winter is in the south, southerners also tend to ignore the rural areas in the north where there is no heating.

Take Hebei Province as an example. In 2019, all 13 cities and 155 counties in Hebei Province achieved centralized heating. However, rural areas, which account for half of Hebei's population, need to rely on their own stoves or electric heaters for heating, and there have been accidents of death from gas poisoning every year in the past.

In terms of warmth, the gap between urban and rural areas, and between rich and poor regions, may be even greater than the gap between the north and south of the heating line. This real gap is the current "main contradiction in our society" - the contradiction between the people's growing needs for a better life and unbalanced and inadequate development. Only adequate and balanced development can ultimately solve the imbalance in warmth, the imbalance in quality of life, and even the imbalance in life.

References:

1. Chen R, Yin P, Wang L, et al. Association between ambient temperature and mortality risk and burden: time series study in 272 main Chinese cities[J]. BMJ, 2018, 363: k4306.

2. "China's natural gas demand will reach 600 billion cubic meters in 2030", Jiemian News

3. Beijing's Energy Development Plan for the 13th Five-Year Plan Period

4. “Is the External Wall Insulation in the South a Waste of Time?——A Discussion on Academician Jiang Yi’s “Is the External Wall Insulation in the South a Waste of Time”, Long Enshen, Electromechanical Information

5. "Energy Savings and Practical Experience of External Insulation Systems (EIFS) in Different Climate Regions of China", Zhang Jie, Shi Peter, Wu Li, Proceedings of the 2006 Second China International Seminar on Production and Application Technology of Building Dry-Mix Mortar

6. “Analysis on the relationship between temperature change and resident mortality in a certain district of Guangzhou from 2000 to 2004”, Qu Yabin et al., Guangdong Provincial Center for Disease Control and Prevention

7. "The Impact of Temperature on Excess Mortality in Three Cities of my country", Zhao Jinqi, Chinese Center for Disease Control and Prevention, 2010

8. “Some southern cities have started central heating to solve the problem of “southerners relying on shivering to keep warm””, Xinhuanet, 2019-11-06

Author: Kuniga 33

Source: Vision