Academic Journal of Science and Technology 
ISSN: 2771-3032 | Vol. 10, No. 2, 2024 

 

207 

Research	on	Energy	Efficiency	and	Carbon	Emission	
Evaluation	Methods	of	cogeneration	Technology	under	
the	Background	of	Carbon	Neutrality	
Yumeng Miao 

Northeastern University School of Metallurgy, Northeastern University, Shenyang, 110819, China 

 

Abstract: This article delves into the energy efficiency evaluation methods and carbon emission evaluation methods of 
cogeneration technology. In terms of energy efficiency evaluation, the concept of energy efficiency and commonly used energy 
efficiency indicators of cogeneration systems were introduced, such as total energy efficiency, power efficiency, thermal energy 
efficiency, and fuel utilization efficiency. In terms of carbon emission evaluation, the concept of carbon emissions and commonly 
used carbon emission indicators for cogeneration systems were analyzed, such as carbon emissions per unit of power generation, 
carbon emissions per unit of thermal energy, and total carbon emissions. For these evaluation methods, different implementation 
steps and calculation formulas were introduced in detail, and their application scenarios and advantages and disadvantages were 
illustrated with examples. These evaluation methods help to evaluate the performance and environmental impact of cogeneration 
systems, providing scientific basis for relevant decision-making. 

Keywords: Combined Heat and Power Generation, Energy Efficiency Evaluation, Carbon Emissions. 
 

1. Introduction 
With the rapid development of global industry and the 

improvement of urbanization level, the demand for electricity 
and thermal energy is also showing a significant growth trend. 
Industrial heat demand accounts for two-thirds of industrial 
energy demand and one-fifth of global energy consumption 
[1]. Cogeneration is an energy production method that utilizes 
primary energy sources such as natural gas and coal for power 
generation, and uses the waste heat generated during the 
power generation process for heating. In the context of carbon 
neutrality, cogeneration technology has become an important 
development direction for global energy technology. 
Compared with traditional single power and heating systems, 
cogeneration systems have many advantages. They can not 
only effectively utilize clean energy, but also form a 
complementary relationship between seasonal gas peaks and 
valleys and electricity load peaks and valleys, alleviating the 
problem of electricity shortage. The cogeneration system can 
simultaneously produce electricity and heat, and effectively 
utilize some waste heat, greatly improving energy utilization 
efficiency [2-4]. This article will discuss the energy efficiency 
and carbon emission evaluation methods of cogeneration 
technology. 

2. Energy Efficiency Evaluation 
Methods for Cogeneration 
Technology 

2.1. The overview of energy efficiency in 
cogeneration 

2.1.1. The concept of energy efficiency in cogeneration 
The energy efficiency of a cogeneration system refers to 

the ratio of the useful energy (electricity and heat) provided 
by the system to the energy consumed (usually fuel). High 
energy efficiency means that the system can generate more 
useful energy with less energy consumption, improve energy 
utilization efficiency, and also have better economic and 

environmental friendliness. 

2.1.2. Common energy efficiency indicators for 
cogeneration 

(1) Total energy efficiency: Total energy efficiency is the 
ratio of the total output of electrical and thermal energy in a 
system to the fuel energy consumed. It evaluates the overall 
energy utilization efficiency of the system, indicating that the 
system converts fuel energy into useful energy with higher 
efficiency [5]. 

(2) Electricity efficiency: Electricity efficiency refers to the 
ratio of the electricity generated by a system to the fuel energy 
consumed. It reflects the energy utilization efficiency of the 
system in terms of electricity generation, and high electricity 
efficiency means that the system can generate more electricity 
with less fuel consumption. 

(3) Thermal efficiency: Thermal efficiency refers to the 
ratio of the heat energy generated by a system to the fuel 
energy consumed. It reflects the energy utilization efficiency 
of the system in terms of thermal energy generation, and high 
thermal energy efficiency means that the system can generate 
more thermal energy with less fuel consumption. 

(4) Fuel utilization efficiency: Fuel utilization efficiency 
refers to the ratio of the useful energy generated by the system 
to the fuel energy consumed. It comprehensively considers 
the output effect of electricity and heat energy, and is a 
comprehensive indicator for evaluating the energy utilization 
efficiency of the system. High fuel utilization efficiency 
indicates that the system is able to utilize fuel energy with 
higher efficiency [6]. 

2.2. Energy efficiency evaluation method for 
cogeneration systems 

2.2.1. Heat sharing method 
In the cogeneration industry, the heat allocation method is 

usually used to calculate the standard coal consumption for 
power generation. This method is based on the first law of 
thermodynamics, treating both electrical and thermal energy 
as heat and allocating them according to the proportion of heat 



 

208 

consumed in heating and power generation. By allocating the 
total coal consumption according to the proportion of heat 
consumption for power generation and heating, the standard 

coal consumption for power generation can be calculated. The 
calculation formula is as follows [7]: 

 

Coal consumption for power generation
Total coal consumption

Power generation Heat supply
1  

 
Heating coal consumption

Total coal consumption Coal consumption for power generation

Heat supply
2

 

 

Total thermal efficiency
Power generation Heat supply

Total coal consumption Calorific value of standard coal
3  

 
The formula for dividing the unit coal consumption of 

different types of units by heat is summarized as follows [8]: 
 

𝑏 ，

，

，

∑
，

           (4) 

 
In the formula: 𝑏 ，  —— The comprehensive power 

generation standard coal consumption (g standard coal/kWh) 
of each type of unit under the heat sharing method; 𝐵 ， —

— Boiler's hourly consumption of standard coal (tons of 
standard coal/h); 𝑊 ， —— Hourly power generation of the 

unit (MWh); 𝑄 ， —— Hourly heating capacity of the unit 

(GJ/h). 
Among them, R is defined as the thermal equivalent of 

electricity (kJ/kWh), and the formula is as follows: 
 

𝑅 𝑅 𝑅                (5) 
 
In the formula: 𝑅 —— Calorific value of standard coal; 

𝑅  —— Equivalent conversion coefficient of electricity to 
standard coal. 

This method can comprehensively consider the energy 
consumption of heating and power generation, and provide a 
comprehensive evaluation of the energy efficiency of 
cogeneration systems. However, this heat allocation method 

did not fully consider the quality difference between 
electricity and thermal energy. Although this method has 
certain applicability in the parameters of high temperature, 
high pressure (or ultra-high pressure) back pressure heating 
units, it is not very suitable for condensing cogeneration units. 
Whether it is the direct heating of the high-temperature and 
ultra-high pressure boiler matched with the back pressure unit, 
or the heating of the back pressure machine with air extraction, 
the heat consumption for heating has not changed, resulting 
in no significant change in the heating ratio. The specific 
calculation methods may vary depending on standards, 
regulations, or corporate practices, so in practical applications, 
appropriate calculation methods should be selected according 
to the situation, and the accuracy and reliability of the data 
should be ensured. 

2.2.2. Referring to the Boiler Law 
In cogeneration, according to the boiler method, the 

amount of coal consumed for heating is equivalent to the 
amount of coal consumed by a standard large coal-fired boiler. 
This method is used to convert the energy consumption 
required for heating into coal consumption corresponding to 
coal-fired boilers for measurement and comparison. At 
present, the heat generation efficiency of standard large coal-
fired boilers is generally set at 0.9. According to the boiler 
method, the calculation formula is as follows [9]: 

 
Heating coal consumption

34.12
Standard large-scale coal-fired boiler heat generation efficiency

6
 

 
Coal consumption for power generation

Total coal consumption Heat supply Heating coal consumption

Power generation
7

 

 

2.2.3. Thermoelectric separation method 
In the selection of design schemes for cogeneration units, 

the combination of centralized heating boilers and pure 
generator units is often compared and demonstrated with 
cogeneration. This method equates the heat generated by 
cogeneration units with the temperature and pressure 
reduction method of directly supplying heat from coal-fired 
boilers. By using this method, the standard coal required for 
the same amount of heat consumed by the central heating 
boiler can be subtracted from the total consumption of 
standard coal in cogeneration, thereby obtaining the standard 
coal consumed by the pure power generation unit [10]: 

 

𝑏 ， 1000
，

，

，

，

          (8) 

 
In the formula: 𝑏 ，  —— The comprehensive power 

generation standard coal consumption (g standard coal/kWh) 
of various types of units under the thermoelectric separation 
method; 𝐵 ， —— Boiler's hourly consumption of standard 

coal (tons of standard coal/h); 𝑄 ，  —— Hourly heating 

capacity of the unit (GJ/h); 𝑅  —— Calorific value of 
standard coal; 𝑊 ，  —— Hourly power generation of the 



 

209 

unit (MWh); 𝑄 ， —— Hourly heating capacity of the unit 

(GJ/h); 𝜂 ，  —— Heating boiler rate (%). Generally, the 

efficiency of large coal-fired heating boilers is approximately 
90%. 

When evaluating the energy efficiency of the cogeneration 
method and the cogeneration unit, it was found that the unit 
coal consumption of the back pressure cogeneration unit was 
lower than that of the condensing cogeneration unit. This 
indicates that the cogeneration method is actually based on a 
reasonable foundation where the heating efficiency of coal-
fired boilers reaches 90%, and electricity is generated by 
conventional condensing units. This coal-fired boiler only 

provides temperature parameters of about 100℃ low-grade 
heat. 

2.2.4. Referring to the Power Plant Law 
In cogeneration, according to the Power Plant Law, the 

amount of coal consumed in power generation is equivalent 
to the amount of coal consumed in coal-fired pure power 
plants. This method is used to convert the energy 
consumption required for power generation into coal 
consumption corresponding to coal-fired pure power plants 
for measurement and comparison. The calculation formula is 
as follows [11]: 

 
Heating coal consumption

Total coal consumption Power generation National average heating coal consumption
Heat supply

9
 

 

2.2.5. Equivalent electrical method 
The equivalent electricity method is an evaluation method 

that comprehensively considers the amount of heating and the 
quality of electricity. It uniformly converts the energy carried 
by steam or hot water of different grades into equivalent 
electricity, assuming that the energy quality coefficient of 
electricity is 1. The energy mass coefficient determined by 
applying the second law of thermodynamics, i.e. the 
equivalent electrical conversion coefficient δ, The heat 
content can be expressed as equivalent electricity using a 
formula. This method balances the importance of heating and 
electricity, providing a comprehensive energy efficiency 
evaluation index [12]: 

 

𝐸 ， 𝛿              (10) 

 
In the formula: 𝐸 ，  —— The equivalent electricity 

quantity of steam or hot water converted according to the 
"equivalent electricity method" is defined as 𝑀𝑊  or 𝑀𝑊 ; 
𝑅  and 𝑅  are the equivalent electrical quantity of steam or 
hot water converted into electricity; 𝛿 —— The equivalent 
electrical conversion coefficient for converting hot water or 
steam of a certain grade parameter into electricity; 𝑄 —— 
Energy carried by steam or hot water (GJ or GJ/h). 

The coal-fired thermal power unit can supply saturated 
steam with a temperature of 𝑇  to the outside world, which 
can release latent heat through isothermal heating and do 
work to reach a saturated water state, and then cool it to 
ambient temperature 𝑇 . Based on the definition of the work 
form of saturated steam in two stages, we can obtain the 
equivalent electrical conversion coefficient 𝛿  for converting 
saturated steam into electricity. This coefficient can quantify 
the efficiency of converting the energy contained in saturated 
steam into electricity and provide an indicator for measuring 
energy conversion efficiency. 

 

𝛿 𝛿 𝛿 1

1 ln ln
       (11) 

 
In the formula: 𝛿  ——The equivalent electrical 

conversion coefficient of converting saturated steam of a 
certain quality parameter into electricity; 𝑟  ——The latent 
heat of vaporization of saturated steam (kJ/kg); ℎ ——The 

enthalpy value of saturated steam (kJ/kg); ℎ  ——The 
specific enthalpy of water at ambient temperature is selected 
as 83.9 kJ/kg; 𝑇  ——Temperature of saturated steam or 
saturated water (K); 𝑇  ——Boiler water replenishment 
temperature (K); 𝑇  ——The final working environment 
temperature (K). 

By converting saturated steam supplied by thermal power 
units into electricity, we can more scientifically analyze and 
evaluate the efficiency of energy processing and conversion 
systems. This method comprehensively considers the 
influence of parameters such as steam pressure, temperature, 
vaporization latent heat, enthalpy, and boiler feedwater 
enthalpy, and can also distinguish the quality differences 
between the two products (electricity and heat) produced by 
cogeneration units. This comprehensive consideration 
approach is more in line with the essence of energy processing 
and conversion in thermal power plants, which is to convert 
low-grade primary energy into high-quality secondary energy 
[13]. 

By converting the supplied saturated steam heat into 
equivalent electrical energy, we can comprehensively 
consider the differences in steam characteristics such as 
pressure, temperature, enthalpy, and latent heat. In this way, 
by using the equivalent electricity method to allocate the 
standard coal consumption of the boiler according to the ratio 
of thermal energy and electrical energy, the calculation 
formula for the standard coal consumption of unit power 
generation can be obtained, as shown below: 

 

𝑏 ，

，

， ，

              (12) 

 
In the formula: 𝑏 ， —— Unit standard coal consumption 

for power generation under equivalent electricity method 
(gram standard coal kWh); 𝐵 ，  —— Boiler's hourly 

consumption of standard coal (tons of standard coal/h); 
𝐸 ， —— Equivalent electricity after steam conversion (MW 

or MWh/h); 𝑊 ， —— Hourly power generation of the unit 

(MWh). 

2.2.6. Exergy efficiency method 
According to the second law of thermodynamics, the 

process of energy conversion is not completely efficient, but 
is limited by energy level differences. When different forms 
of energy are converted into other forms, there is energy loss. 
The concept of energy levels is described using the ratio of 



 

210 

exergy to enthalpy in thermodynamics [14]. In a cogeneration 
system, the chemical energy of electricity and fuel can be 
completely converted into thermal energy, with an exergy to 
enthalpy ratio of 1. However, when converting thermal energy 

into mechanical energy and further into electrical energy, the 
conversion rate is limited by Carnot's law. The formula is as 
follows [15]: 

 

The ratio of exergy to enthalpy
Exergy

Enthalpy
13  

 
Exergy efficiency=Total thermal efficiency×

1 The exergy to enthalpy ratio of supplied heat energy Heat-to-electric ratio

1 The exergy to enthalpy ratio of electric energy Heat-to-electric ratio
100%

14  

 

3. Carbon Emission Evaluation 
Method for Cogeneration 
Technology 

3.1. The overview of carbon emission 
evaluation for cogeneration 

3.1.1. The concept of carbon emissions in cogeneration 
The carbon emissions of cogeneration systems refer to the 

greenhouse gases released by the system during the 
combustion of fuel, generation of electricity, and heat, mainly 
carbon dioxide. The combustion of fuel is the main source of 
carbon emissions, and factors such as energy efficiency and 
fuel selection in cogeneration systems will directly affect 
carbon emissions. Reducing carbon emissions from 
cogeneration systems is one of the important means to reduce 
greenhouse gas emissions and address climate change. 

3.1.2. Common carbon emission indicators for 
cogeneration 

(1) Carbon emissions per unit of electricity generation: 
Carbon emissions per unit of electricity generation refer to the 
amount of carbon dioxide released by a system for every unit 
of electricity generated. It is a key indicator for evaluating the 
carbon emission effect in the power generation process of the 
system. A lower unit of carbon emissions from power 
generation indicates that the system generates electricity with 
lower carbon emissions. 

(2) Unit thermal carbon emissions: Unit thermal carbon 
emissions refer to the amount of carbon dioxide released by a 
system for every unit of thermal energy generated. It reflects 
the carbon emission effect of the system during the heating 
process. A lower unit of thermal energy carbon emissions 
indicates that the system generates thermal energy with lower 
carbon emissions. 

(3) Total carbon emissions: Total carbon emissions refer to 
the total amount of carbon dioxide released by the system 
during the entire energy conversion and utilization process. It 
comprehensively considers the output effects of electricity 
and heat, and is a comprehensive indicator for evaluating the 
carbon emissions of the system. Reducing total carbon 
emissions can reduce the negative impact of the system on 
climate change [16-17]. 

3.2. Carbon emission evaluation method for 
cogeneration systems 

3.2.1. Benchmark method 
The benchmark method is a commonly used carbon 

emission evaluation method that compares the carbon 
emissions of a cogeneration system with a certain benchmark 
system. The benchmark system is usually the same type of 
traditional energy system, such as independent power 

generation and heating systems. The core idea of this method 
is to evaluate the carbon reduction effect of a cogeneration 
system by comparing the carbon emissions of two systems. 
When implementing, first determine the carbon emissions of 
the benchmark system, then measure or estimate the carbon 
emissions of the cogeneration system, and compare and 
analyze the two. The advantage of the benchmark method is 
that it is simple and intuitive, easy to understand and apply 
[18]. 

The application summary in article Research on Carbon 
Emission Benchmarks and Carbon Reduction Potential of the 
Central Heating Industry in Jilin Province under the 
Background of" Dual Carbon" is as follows [19]: 

(1) Data collection and accounting: Based on 
environmental statistical data from 2011 to 2020, calculate the 
carbon emissions of the central heating industry over the 
years. This includes calculating the carbon emissions per unit 
area of cogeneration heating enterprises during this period.  

(2) Benchmark selection: Based on urban characteristics 
and heating demand, select the "coal consumption emission 
scenario" and "cogeneration emission scenario" as carbon 
emission benchmarks. These scenario models consider the 
changing characteristics of carbon emissions in the central 
heating industry in Jilin Province.  

(3) Carbon emission intensity analysis: Analyze the carbon 
emission intensity of the heating industry in various cities 
throughout the province, classify the levels based on the 
average carbon emissions of each city over the years, and 
establish a baseline for carbon emissions based on this.  

(4) Research on Carbon Reduction Potential: Based on the 
selected baseline, analyze the carbon reduction potential of 
the industry. The research results indicate that the carbon 
emission reduction of the central heating industry in Jilin 
Province is 11.7837 million tons per year, with a carbon 
reduction potential of 37.5%.  

(5) Conclusion: The research results indicate that the 
heating method of cogeneration is the dominant source of 
carbon reduction potential. At the same time, considering 
environmental protection and regional development 
characteristics, we cannot blindly reduce the coal 
consumption of cogeneration enterprises.  

In summary, this method aims to achieve low-carbon 
transformation and sustainable development of the central 
heating industry through scientific evaluation and reasonable 
planning. 

3.2.2. Process analysis method 
Process analysis method is a detailed analysis method for 

various processes of cogeneration systems, including fuel 
combustion, energy conversion, and waste heat utilization. 
This method measures and calculates the carbon emissions of 
each process to obtain the total carbon emissions of the 



 

211 

system. The process analysis method can help identify the 
main sources of carbon emissions in the system, thereby 
guiding the development of emission reduction measures. 
When implementing, it is necessary to collect data from 
various processes, such as fuel consumption, combustion 
efficiency, and waste heat utilization rate, and then calculate 
the carbon emissions of each process and accumulate them to 
obtain the total carbon emissions of the system. The general 
steps for calculating carbon emissions using process analysis 
can be summarized as [20-21]: 

(1) Data collection: Collect energy consumption data of 
thermal jump generation facilities, including fuel types (such 
as coal, natural gas, etc.) and consumption. Obtain power 
generation and heating data for cogeneration facilities.  

(2) Determine carbon emission factors: For each fuel, 
determine its carbon emission factor. These factors can 
usually be found in IPCC guidelines or other official 
published data.  

(3) Calculate the carbon content of the fuel: Calculate the 
amount of carbon dioxide produced during fuel combustion 
based on its beauty and calorific value. This usually involves 
the carbon oxidation rate of the fuel and the net calorific value 
of the fuel.  

(4) Calculate carbon emissions: Calculate the total carbon 
dioxide emissions using the following formula: 

 
𝐶 𝐸 𝑁𝐶𝑉 𝐶𝐸𝐶 𝐶𝑂𝐹         (15) 

 
In the formula: 𝐶 —— The total carbon emissions 

generated by fuel combustion (unit: 10000 tons); 𝐸—— Fuel 
consumption (unit: 10000 tons of standard coal); 𝑁𝐶𝑉 —— 
Net calorific value of fuel (unit: TJ/Gg); 𝐶𝐸𝐶 —— Carbon 
emission factor (unit: kg 𝐶𝑂  /GJ); 𝐶𝑂𝐹 —— The carbon 
oxidation rate of fuel, usually taken as 1; 44/12—— 
Molecular weight ratio of carbon dioxide to carbon. 

(5) Adjustment and verification: Adjust the calculation 
results to consider possible errors and uncertainties. Use on-
site monitoring data or third-party validation data to select 
rows for verification, ensuring the accuracy of calculations. 

3.2.3. Input-output analysis method 
The input-output analysis method is based on material and 

energy flows to analyze the input and output of a cogeneration 
system. This method considers the energy input and output of 
the system, and calculates the carbon content to evaluate the 
carbon emissions of the system. The input-output analysis 
method comprehensively considers the energy conversion 
efficiency and energy utilization of the entire system. When 
implementing, first collect input data from the system, 
including fuel type, usage, and carbon content, and then 
measure or estimate the energy output and carbon emissions 
of the system. By comparing and analyzing inputs and outputs, 
the carbon emission performance of the system can be 
evaluated [22]. 

3.2.4. Life cycle assessment method 
The life cycle assessment method considers the carbon 

emissions of cogeneration systems throughout their entire life 
cycle, from construction, operation to disposal. This method 
comprehensively considers the carbon emissions of various 
links such as raw material collection, equipment 
manufacturing, transportation, use, and treatment. By 
assessing carbon emissions throughout the entire lifecycle, a 
comprehensive understanding of the environmental impact of 
the system can be obtained. When implementing, it is 

necessary to collect data from various links, such as material 
and energy consumption, transportation distance, and waste 
disposal methods, and then calculate the carbon emissions of 
each link, and accumulate them to obtain the total carbon 
emissions of the system [23]. The following is the application 
of the life cycle assessment method for cogeneration to 
calculate carbon emissions [24]: 

(1) Definition of objectives and scope: Clearly define the 
purpose of the evaluation and the research question. 
Determine system boundaries, including upstream (raw 
material extraction and processing), midstream (cogeneration 
equipment manufacturing and installation), and downstream 
(operation and maintenance) stages. 

(2) Data collection: Collect data on all activities related to 
cogeneration, including raw material production, equipment 
manufacturing, transportation, installation, operation, 
maintenance, retirement, and waste disposal. 

(3) Life Cycle Inventory (LCI) analysis: Quantify energy 
consumption and emissions for each stage, including fossil 
fuel consumption, electricity consumption, water 
consumption, waste generation, etc. Determine the 
greenhouse gas emissions generated by each activity, 
including carbon dioxide, methane, nitrous oxide, etc. 

(4) Life Cycle Impact Assessment (LCIA): Using LCIA 
methods to assess the environmental impact of greenhouse 
gas emissions, typically expressed as Global Warming 
Potential (GWP). Calculate the carbon emission impact of 
each activity, including direct emissions (such as those 
generated by combustion) and indirect emissions (such as 
emissions from electricity production processes). 

(5) Explanation and improvement of results: Analyze the 
results, identify the main sources and influencing factors of 
carbon emissions. Compare the impact of different 
technological paths or management measures on carbon 
emissions. Propose improvement measures based on the 
results of the life cycle assessment to reduce carbon emissions 
in the cogeneration process. 

The life cycle assessment method not only focuses on the 
direct carbon emissions of cogeneration, but also considers 
the environmental impacts of the entire system, including 
resource consumption, waste generation, and ecological 
impacts. This method helps to comprehensively understand 
the environmental footprint of cogeneration and provides 
scientific basis for emission reduction strategies. 

4. Conclusions 
Driven by the goal of carbon neutrality, cogeneration (CHP) 

technology will usher in new development opportunities. In 
the future, the CHP system will pay more attention to 
improving energy efficiency and reducing carbon emissions. 
By integrating advanced energy conversion technologies, 
intelligent control and energy management systems, as well 
as deep integration with renewable energy, it will achieve 
efficient energy utilization. Energy efficiency evaluation 
methods will tend to be more refined and comprehensive, 
focusing not only on the utilization efficiency of a single 
energy source, but also on the overall energy flow and carbon 
footprint of the system. The carbon emission assessment 
method will be combined with the life cycle assessment 
method to comprehensively evaluate the full life cycle carbon 
emissions of the CHP system, providing scientific basis for 
formulating emission reduction strategies. With the 
advancement of data collection and analysis technology, 
evaluation methods will become more accurate and real-time, 



 

212 

providing strong support for policy formulation and 
enterprise operation. 

References 
[1] Zhang Zhizu, Zhang Weiyi, Liu Azhen, et al. Research status 

of cogeneration application technology at home and abroad [J]. 
Journal of Beijing Institute of Petrochemical Technology, 2020, 
28(02): 29-39. 

[2] Han Yongshun. Application and Analysis of Combined Heat 
and Power Generation Systems [C] //Proceedings of the 2021 
Symposium on Heating Engineering Construction and 
Efficient Operation by China North China Municipal 
Engineering Design and Research Institute Co., Ltd. and China 
Construction Technology Group Co., Ltd Gas and Heat 
Magazine, 2021:3. 

[3] Wang Guangqi. Energy saving technology exploration of 
cogeneration centralized heating system [J]. Xinjiang 
Nonferrous Metals, 2023，46(02):96-97. 

[4] Peng Guiyun, Key Technologies and Applications of Flexible 
and Efficient Heating in the Integrated Heat and Power 
cogeneration System of Source, Grid, and Load. Zhejiang 
Province, Huadian Electric Power Research Institute Co., Ltd., 
2020-06-11. 

[5] Genovski I ,Hristov K .Model research of the energy efficiency 
of a cogeneration backpressure steam turbine installation [J]. 
E3S Web of Conferences,2020,20702004-. 

[6] Alessandra M A ,Lisa B ,Saverio O , et al.Energy and 
Environmental Assessment of Cogeneration in Ceramic Tiles 
Industry [J]. Energies,2022,16(1):182-182. 

[7] Obida Z ,Jamel O ,UdDin S K , et al.Desalinated Water Costs 
from Steam, Combined, and Nuclear Cogeneration Plants 
Using Power and Heat Allocation Methods [J]. Energies, 2023, 
16(6): 2752-2752. 

[8] Yu Peiyuan, Song Xiaoyan. Exploration of energy efficiency 
indicators for cogeneration units [J]. Green Technology, 2021, 
23(18): 204-205+208. 

[9] Yanan C ,Yoalbys R ,Abel H , et al.Energy efficiency 
indicators of the steam boiler in a power plant of Cuba [J]. 
Thermal Science and Engineering Progress,2021,23. 

[10] Chen Yinli. Heating operation and regulation methods of 
cogeneration and comparison of energy efficiency of 
cogeneration [J]. A low-carbon world, 2020,10(01):54-55. 

[11] Hasan M M ,Afrin S J ,Mamun R , et al.Energy and Exergy-
Based Efficiency, Sustainability and Economic Assessment 
towards Improved Energy Management of a Thermal Power 
Plant: A Case Study[J].Sustainability,2023,15(6):5452-5452. 

[12] Sun Tonghui. Evaluation of energy efficiency indicators for 
backpressure cogeneration units [J]. Energy conservation, 
2020,39(09):49-53. 

[13] Li Y ,Mi P ,Li W , et al.Full operating conditions optimization 
study of new co-generation heating system based on waste heat 
utilization of exhausted steam[J].Energy Conversion and 
Management, 2018,15591-99. 

[14] Navid M ,Parisa M ,Shahram K .Multi-objective optimization 
of power, CO2 emission and exergy efficiency of a novel solar-
assisted CCHP system using RSM and TOPSIS coupled 
method [J].Renewable Energy,2022,185506-524. 

[15] SurywanshiD G ,LeionH ,SoleimanisalimH A .Energy, Exergy, 
Economic and Exergoeconomic Analyses of Chemical 
Looping Combustion Plant Using Waste Bark for District Heat 
and Power Generation with Negative Emissions[J].Energy 
Technology, 2023,12(2). 

[16] Babkir A ,M. H ,Ahmed G .Sustainability assessment of 
alternative energy power generation pathways through the 
development of impact indicators for water, land, GHG 
emissions, and cost[J].Renewable and Sustainable Energy 
Reviews, 2023,171. 

[17] Marrasso E ,Roselli C ,Sasso M .Electric efficiency indicators 
and carbon dioxide emission factors for power generation by 
fossil and renewable energy sources on hourly basis[J].Energy 
Conversion and Management,2019,1961369-1384. 

[18] Li X ,Gu Y ,Wang Z .Energy Efficiency State Identification for 
Cogeneration Units Based on Benchmark Value [J]. Processes, 
2023, 11(10). 

[19] Lin Xiaosheng, Shi Shuangming, Wang Yu, etc Research on 
Carbon Emission Benchmarks and Carbon Reduction Potential 
of the Central Heating Industry in Jilin Province under the 
Background of "Dual Carbon".Green Technology, 2023, 
25(02): 132-136+141. 

[20] Yang Haonan. Heat transfer process analysis and thermal 
layout optimization of multi cooling plate thermoelectric 
refrigeration modules [D]. Zhengzhou University, 2022. 

[21] Zhou Dinglin. Analysis of Carbon Emissions from Direct 
Living Energy of Chinese Residents and Research on Emission 
Reduction Pathways [D]. Huazhong University of Scienceand 
Technology, 2023. 

[22] Secui C D ,Hora C ,Bendea G , et al.Parameter estimation using 
a modified whale optimization algorithm for input‐output 
curves of thermal and hydro power plants[J].International 
Transactions on Electrical Energy Systems,2020,30(2):n/a-n/a. 

[23] Ayumi Y ,Shoma F ,Yuichiro K , et al.Life cycle greenhouse 
gas emissions of cogeneration energy hubs at Japanese paper 
mills with thermal energy storage[J].Energy,2023,270. 

[24] Liu Jieli. Accounting method for carbon emission cost of 
power generation units and its application in life cycle cost 
analysis [D]. Zhejiang University,2018.