Shulou(Shulou.com)11/24 Report--

This article comes from Weixin Official Accounts: Earth Knowledge Bureau (ID: diqiuzhishiju), author: Zheng Lingjun, proofreading: Chao Qian, editor: chestnut

When it comes to central heating, the northern partners may be familiar with it. In their memory, many years ago, many family homes had their own coal-fired hot water boilers to heat the community. Later, in order to save energy and protect the environment, the state began to implement central heating, using centralized heat sources to provide production and living heat to enterprises and residents in surrounding areas through heating networks.

When it comes to nuclear power, many small partners may not be too unfamiliar. Overlooking China's mainland coastline like a bow, 18 nuclear power bases distributed in eight coastal provinces are strung into chains, building a solid foundation for China to move from a nuclear power to a nuclear power.

Nuclear energy as a clean energy source

It plays an important role in China's future energy map

(Distribution of nuclear power plants in commercial operation in China) ▼

However, nuclear power and central heating together may make many people feel novel.

Can nuclear power be used for heating? On November 1,2022, as the first nuclear energy heating project in Northeast China, Liaoning Hongyanhe Nuclear Power Plant Nuclear Energy Heating Demonstration Project was officially put into operation, providing winter heating guarantee for nearly 20,000 local residents.

Hongyanhe Nuclear Power Plant is the first nuclear power plant in Northeast China and the largest electric power energy investment project in Northeast China at present. Six nuclear power units have been built with a total installed capacity of about 6.713 million kilowatts, which is the largest nuclear power plant in operation in China at present.

Unit 6 of Hongyanhe Nuclear Power Plant realized commercial operation in June this year

With Unit 6 connected to the grid, Hongyanhe Nuclear Power Plant has become the third largest nuclear power plant in the world.

(Map of Hongyanhe Nuclear Power Plant: en.cgnp.com.cn) ▼

The planned heating area of Hongyanhe Nuclear Power Station Nuclear Energy Heating Demonstration Project is 242,400 square meters. Steam extraction from steam turbine of Hongyanhe Nuclear Power Station is used as heat source to replace the original 12 coal-fired boiler houses in Hongyanhe Town. Nearly 10 kilometers of primary pipe network, 5.7 kilometers of secondary pipe network and 4 heat exchange stations will be built.

After the project is put into operation, it has remarkable environmental protection benefits, which can reduce the consumption of standard coal by 5726 tons, reduce carbon dioxide by 14,100 tons, sulfur dioxide by more than 60 tons and ash by 2621 tons every year.

The Red River Nuclear Power Plant warms residents while

It also protects a blue sky in Hongyanhe Town

(Installation site diagram of primary pipe network of nuclear heating project: china-nea. cn) ▼

You might feel like grandma Liu is new to Cybertron, and that leads to the idea that nuclear energy can be used for heating? "" Will the water radiation in the heater exceed the standard? "Wait for questions and even worry.

After all, in the memory of many northerners, heat sources are generally cogeneration thermal power plants, coal-fired or gas-fired heating boilers, industrial waste heat, etc., and nuclear power is irrelevant.

Nuclear heating, however, is not a new technology. In the 1960s, the Swedish prototype nuclear power reactor Agesta was built and put into operation, becoming the world's first civilian nuclear heating nuclear power plant.

Nuclear heating expands the boundaries of nuclear applications

to see more possibilities for nuclear power.

Arvid Nilsson, AB Atomergi

Since then, many countries have begun to use nuclear energy for heating. About one tenth of the more than 400 nuclear power units currently in operation around the world have realized cogeneration.

How big is the heating industry market space? In recent years, the scale of China's urban heating industry has grown steadily. According to the data of the Ministry of Housing and Construction and the National Bureau of Statistics, from 2012 to 2021, the total urban heat supply in China increased from 2.954 billion GJ to nearly 4.2 billion GJ, with an annual growth rate of 3.98%.

Among them, the total amount of steam heating increased from 516 million GJ to 649 million GJ, with an annual growth rate of 2.57%; the total amount of hot water heating increased from 2.438 billion GJ to 3.548 billion GJ, with an annual growth rate of 4.26%.

Some southern cities that started heating also contributed some data ▼

With the rapid progress of urbanization in China, the area of central heating and heating pipeline mileage are also increasing year by year. According to the relevant statistical data of the Ministry of Housing and Construction of China, by the end of 2021, the central heating area in China has reached 10.603 billion square meters, with an average annual growth rate of 8.28% in recent ten years.

The growth of the total heating area is very stable

Approximate to a straight line ▼

Among them, Shandong and Liaoning heating area has exceeded 1 billion square meters; China's central heating pipeline length has also reached 426,000 kilometers (2020), an increase of 1.66 times compared with 2012.

Driven by the drive for a better life,

This number will continue to grow.

In the early days, distributed heating mode was mainly adopted in northern China, and the main heat source was small coal-fired boiler, which had high energy consumption, low heating efficiency, and no post-treatment device, so the pollution was serious.

In order to meet the requirements of energy conservation, emission reduction and green environmental protection, the state began to vigorously promote centralized heating, using cogeneration and large heating boilers as heat sources, and gradually eliminating small coal-fired boilers.

We all know that the higher the parameters of coal-fired boilers, the higher the efficiency. Cogeneration can realize cascade utilization of coal-fired power plant energy, higher energy utilization rate, can significantly reduce energy consumption, but also can only cover a certain range of areas around the thermal power plant.

For those areas where there is no thermal power plant nearby, large-scale heating boilers will be built to provide heat, and the coal that was originally scattered will be concentrated. With higher parameters and less leakage, the natural energy efficiency will also increase. Therefore, the primary energy source relied on by central heating in China is mainly coal.

With the improvement of people's living standards, the demand for heating will gradually increase, China's urban heating market will still maintain a rapid growth rate, some research institutions predict that China's total heat supply within five years or will exceed 5 billion gigatoules.

That means there's about 800 million gigajoules of room for growth. So what tops this 800 million GJ growth?

What does winter heating depend on? Although coal is the largest primary energy source in our country, we cannot leave coal and coal power at present, but in the long run, in order to realize carbon neutralization, coal is bound to have a process of reduction.

According to the relevant documents of the central government, in terms of coal consumption, China will speed up the pace of coal reduction, strictly control the growth of coal consumption during the "14th Five-Year Plan" period, gradually reduce it during the "10th Five-Year Plan" period, and gradually reduce it until coal scattered burning is prohibited.

China's commitment to emission reduction is true

This is what a big country should have.

In terms of coal power, we will coordinate the development of coal power and ensure peak supply, strictly control new coal power projects, reach the international advanced level of coal consumption standards for new units, orderly eliminate backward coal power production capacity, speed up energy conservation upgrading and flexibility transformation of active units, actively promote heating transformation, and promote the transformation of coal power to basic guarantee and system regulation power supply.

The status of coal power as a basic power source is still difficult to replace

Clean and efficient is the green transformation of coal power ▼

Therefore, among the new heating in the future, the highest priority may be to use the heating transformation of surrounding coal-fired power stations, so that coal-fired power units can provide heat energy for surrounding industrial enterprises and residents while generating electricity, so as to promote the cascade utilization of energy to the greatest extent.

A power plant that uses heat to transform can still contribute a lot of heat

Natural gas, as a relatively clean and low-carbon fossil energy source, is indeed a good thing, flexible in utilization, high in calorific value and low in pollution. It has also become an important supporting energy source for Europe's clean and low-carbon transition. However, the natural gas chaos in Europe brought about by the Russia-Ukraine conflict also makes us realize more deeply the importance of "holding the rice bowl in our own hands".

At present, China's dependence on natural gas has reached 45%. If all the new heating demand is supplied by gas power generation or natural gas energy station, where the gas comes from will become a very urgent problem. Once the dependence on foreign countries is too high, it is easy to be stuck, especially the application of natural gas basically involves all aspects of China's production and life.

Natural gas dependence on foreign countries is increasing day by day

Finding alternative energy sources is even more important.

Nearly 1/6 of natural gas is used for power generation and heating.

On the issue of heating energy in winter, according to the regular session of the State held on January 8 last year,"we should adhere to the principle of coal, electricity and gas, and continue to ensure the heating energy of the masses, especially in the northern regions."

In other words, we should try our best to strike a balance between clean and low carbon, affordable cost and available resources. Biomass clean heating, geothermal heating, low-grade waste heat heating, nuclear waste heat heating can occupy a place.

How does nuclear power heat up? Nuclear energy is characterized by high efficiency and durability. At present, there are two ways for human beings to use nuclear energy: nuclear fission and nuclear fusion.

Nuclear fission has reached the practical stage, atomic bombs have been built in the military field, and many nuclear power plants have been built in the energy field. Although nuclear fusion has produced hydrogen bombs in the military field, the energy field is still in the stage of scientific and technological breakthrough and has not yet achieved commercial success.

Fusion releases far more energy than fission.

It's too hard to control it without destroying it.

(hydrogen bomb explosion as the destruction map: USDOE) ▼

Therefore, at present, nuclear power generation mainly uses uranium-235 nuclear fission chain reaction to release a large amount of heat energy, using this heat energy to turn water into steam, and then using steam to drive steam turbines to drive generators to generate electricity.

When thermal neutrons bombard U-235 atoms, they emit two to four neutrons.

Neutrons then collide with other uranium atoms, forming a chain reaction and spontaneous fission.

(Photo: IAEA) ▼

At first glance, it seems to be very similar to coal power plants. The main difference lies in the difference between "boilers": boilers in coal power plants are coal-fired boilers, while "boilers" in nuclear power plants are nuclear reactors. The professional term is "nuclear island", which refers to containment and all its internal equipment or systems.

Nuclear reactors are much more productive than boilers.

Safety measures are not on the same level as boilers.

(Photo: wiki) ►

This "containment vessel" consists of prestressed reinforced concrete, and a steel containment vessel can be added to the prestressed reinforced concrete containment vessel to withstand even the high-speed impact of commercial aircraft.

The core is the core of the nuclear island, mainly composed of fuel assemblies and control rod drive systems. The fission chain reaction releases a large amount of heat, which is absorbed by the water in the core and flows through the steam generator through the primary circuit, exchanging heat with the water in the secondary circuit.

The heat released by nuclear fission is amazing.

Cooling is an extremely important part of controlling nuclear reactions.

(Core Design Drawing: wiki) ▼

The process after the second loop is the same as that of coal power plant. The water in the second loop is heated and converted into steam with certain parameters, which drives the steam turbine to run and drives the generator to generate electricity.

In this process, the water of the first circuit and the second circuit is completely isolated. For safety reasons, the core is placed in a steel pressure vessel, and the pressure vessel, primary piping, main pumps, and steam generators are placed in containment.

All risk factors are "locked" by containment.

(Photo: IAEA) ▼

Nuclear heating is mainly to extract steam from the second circuit of nuclear power unit as heat source, conduct multi-stage heat exchange through the first station of heat exchange in the plant and the heat exchange station outside the plant, and finally transfer heat to the end user through the municipal heating network. Its principle and coal power plant heating are the same, are waste heat utilization.

There are multiple circuits between nuclear power plants and heating users for isolation. There is only heat transfer between each circuit and no water exchange, so residents do not have to worry about radiation.

Zero radiation, zero carbon.

You can use it with confidence

(Photo by OECD)

Nuclear heating has been widely used worldwide. From the practice of nuclear heating at home and abroad, the safety and reliability of nuclear heating have also been proved.

Safe and reliable nuclear heating can be more than just heating

Humans are already trying to figure out how to squeeze nuclear heat out of its value in all sorts of ways.

(Photo: IAEA) ▼

Even in our country, Hongyanhe nuclear heating is not our first attempt in this field. Before this, Shandong Haiyang and Zhejiang Haiyan have entered the "nuclear heating era."

For example, the "Warm Nuclear No.1" heating project put into operation in November 2019, such as Shandong Haiyang Nuclear Power Plant, makes Haiyang City become the first "zero-carbon" heating city in China, realizing win-win situation among local people, local government, thermal power company, nuclear power enterprise and ecological environment protection.

Although nuclear power is not a renewable energy source, compared with wind power and photovoltaic, nuclear power has a greater advantage in stability. With the promotion of "double-carbon" work by the state after establishment, nuclear power, as a clean energy source, has received more and more attention in recent years.

At present, China ranks third in the world in terms of installed capacity of nuclear power units in operation, with a total of 53 units and 55.53 million kilowatts (94.718 million kilowatts in operation in the United States, ranking first; 61.37 million kilowatts in operation in France, ranking second).

China's nuclear power installed capacity growth is fast and slow

But it keeps growing.

The installed capacity of units under construction in China ranks first in the world, with a total of 23 units and 24.19 million kilowatts. By 2025, the installed capacity of nuclear power put into operation will reach about 70 million kilowatts, surpassing France to become the second largest nuclear power installed capacity in the world (currently, the units under construction in France are only about 1.63 million kilowatts).

However, there is still room for improvement in the penetration rate of nuclear power in China. At present, the proportion of nuclear power generation in China's total power generation is less than 5%, although it shows an increasing trend year by year, it is still lower than the proportion of new energy sources and significantly lower than the level of many developed countries.

The current low percentage also shows the great potential of nuclear development

China's Nuclear Power Future

In the Guiding Opinions on Energy Work in 2022, the National Energy Administration proposed to organize the implementation of the Pilot Program for Central Heating and Comprehensive Utilization of Nuclear Energy to promote the comprehensive utilization of nuclear energy. Nuclear energy heating is within the scope of comprehensive utilization of nuclear power.

According to the plan, by 2025, the installed capacity of nuclear power operation in China will reach about 70 million kilowatts. At that time, more cities will feel the warmth from nuclear energy.

Source of data:

1. National Bureau of Statistics

2. Ministry of Housing and Urban-Rural Development: Bulletin on China's Urban Construction Status in 2021

3. World Nuclear Association,

4. International Atomic Energy Agency

* This article is provided by the author and does not represent the position of the Earth Knowledge Bureau.

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