Research on The Application of Distributed Photovoltaic Power Generation Along the Service Area of Tangquan Pool of Dabie Mountain Expressway

Jiangchao Han Peng Wang JiTao Wang

（1.NO.Three Engineering Co.Ltd.Of CCCC First Highway Engineering Co,Ltd,Beijing 101102;2.Shang Luo Highway Co.,Ltd.Of Henan Transort Investment Group Co,Ltd,Henan Zhengzhou 450000）

Abstract: Abstract: Under the background of recycling and low carbon,the recycling of site resources in the expressway service area is an effective form of green intensification,and the distributed solar photovoltaic is well made full use of the spatial function of the service area,and the grid-connected power generation system of energy conservation and emission reduction is better established.Following the idea that energy is the continuous driving force for the development of human society and distributed photovoltaic power generation industry is an important part of renewable energy,the paper explores the innovative application of distributed photovoltaic power generation industry in the service area of Tangquan Pool,actively tracks the development of new technologies,and prefers clean energy over traditional ones,with a view to reducing carbon emissions,improving savings,continuously reducing energy consumption and carbon emission intensity of transportation equipment throughout the life cycle of expressways,and creating a good ecological operating environment.

Keywords: Service area;Innovation leadership;Photovoltaic power generation;Circular low carbon;Green intensification;Clean energy

The report of the 20th National Congress of the Communist Party of China pointed out that green development should be promoted and harmonious coexistence between man and nature should be promoted.Under the premise of implementing the highway construction concept of ＂six persistences and six establishments＂,on the basis of circular development and low-carbon development,and in the application of new technologies such as low-carbon,energy-saving and environmental protection,the construction of safe,reliable,green and intelligent highways is implemented to complete the strategic goal of green cycle and lowcarbon transportation system.As a power transmission station of the expressway,the service area has a large site space area and has a large potential of circulating lowcarbon hub,giving full play to the green and low-carbon transmission role of the service area and providing energy supply for energy conservation and low-carbon along the highway,which plays a vital role.

1 Construction of Photovoltaic Power Generation System in Tangquan Pool Service Area Along Dabie Mountain Expressway

1.1 Demand for Clean Energy

At present,the energy utilization is as high as nearly 70% with the help of traditional fossil fuels and coal mining,and non-fossil energy accounts for only about 10%,and the process of fossil energy resource utilization and energy conversion has produced greater pollution,causing great damage to the environment.To carry out the energy revolution under the premise of sustainable development,change the energy structure,reduce environmental pollution and ecological environment damage,it is necessary to transform from the current high-carbon to the low-carbon of the future,and develop clean and low-carbon new energy to ensure the security of energy supply,which is a necessary measure to solve the limited amount of traditional energy,large environmental impact,and low proportion of non-fossil energy.At the same time,to implement the requirements of the national Energy Production and Consumption Revolution Action Plan (2030),the energy revolution with clean energy development as a means is also the focus of promoting the development of green transportation.

1.2 Requirements for Low-Carbon Construction in Service Areas

In recent years,the transportation industry has put forward higher requirements for the construction of service areas,and the Opinions on Further Improving the Service Quality of Expressway Service Areas in 2014 put forward the requirements for strengthening the construction of green service areas,and the Guiding Opinions on the Implementation of Green Highway Construction listed ＂promoting the construction of green service areas＂ as one of the five major special actions,requiring the implementation of new technology applications such as sewage treatment,building energy saving,clean energy,and garbage disposal in service areas.

Solar energy is a clean,efficient and never-exhausting energy source,and making full use of solar energy is of great significance to reducing energy conservation and carbon reduction.Photovoltaic power generation is a renewable and pollution-free power generation method that uses the photovoltaic effect of photovoltaic cells to directly convert the light energy of sunlight into electrical energy,which has no risk of exhaustion;High energy quality,safe and reliable,no noise,no pollution discharge,absolutely clean (no pollution);It is not limited by the geographical distribution of resources,and can take advantage of the building roof;On-site power generation and power supply without fuel consumption and transmission lines;The construction period is short,the time to obtain energy is short,and according to the distribution table of ChinaIs solar energy resources released by the National Energy Administration,Henan belongs to the area with rich solar energy resources,suitable for the construction of photovoltaic power stations.Highspeed service areas,toll stations and other stations,with scattered locations and large areas,are suitable for setting up distributed photovoltaic power generation systems.

1.3 Photovoltaic Power Generation Construction Mode

The section from Jigongshan to Shangcheng along the Dabie Mountain Expressway (hereinafter referred to as the ＂Project＂) is the first batch of cutting projects of the provincial expressway ＂13445＂,with a total length of 123.32 kilometers,which for the first time penetrates the traffic arteries on the border lines of Henan,Hubei and Anhui provinces,and actively promotes the strategic concept of transportation integration in the Dabie Mountain Area of Hubei-Henan-Anhui,which is of great significance for promoting the economic and social development and tourism resource development of the Dabie Mountain Revolutionary Old Area,consolidating the achievements of poverty alleviation in the Dabie Mountain District,and realizing coordinated regional development.

Fig1.Rendering of Tangquan Pool Service Area

In view of the above engineering characteristics,the project fully implements the Guiding Opinions on the Implementation of Green Highway Construction issued by the Ministry of Transport,takes ＂innovation-led and green intensive＂ as the main line,implements the overall idea of ＂backward thinking in the planning stage and positive optimization in the implementation stage＂,and runs the green highway construction concept of ＂energy saving,resource-saving,environmental friendliness,smooth and durable＂ through the whole life cycle of design,construction,operation and management of the section from Jigongshan to Shangcheng along the Dabie Mountain Expressway,focusing on the green goals of different implementation stages.Carry out the design and construction of integrated systems for photovoltaic power generation,energy storage and electric vehicle charging,and achieve the overall goal of green highway construction of the project.

2 Design Of Photovo ltaic Power Generation System in Tangquan Pool Service Area

2.1 Design Concept

2.2.1 Innovation leadership

Innovation is a strong driving force for highway development,and the project runs innovation through all aspects of highway construction to create a road of science and technology led by innovation.In view of a series of problems faced by the comprehensive application of distributed photovoltaic applications (laying photovoltaic power generation panels,charging piles or charging station construction,distributed energy storage systems) in the project,through targeted scientific and technological research,digestion,absorption and re-innovation of existing scientific and technological achievements,and the promotion and application of mature technologies,construction safety is guaranteed,project quality is guaranteed,and the level of engineering scientific and technological innovation is improved.

2.2.2 Green intensification

The construction of green roads is the call of the times,and the project should focus on strengthening ecological protection and coordinating the utilization of resources,and creating a green road that is resource-saving and environmentally friendly.The ecological environment along the project is sensitive,and it is necessary to adhere to the guidelines of ecological priority and harmonious development,strengthen the protection of ecological environment at all stages such as design,construction,operation and maintenance,and achieve maximum protection,minimum impact,and most vigorous natural restoration,so as to achieve the healthy and sustainable development of highways,ecology and society.

2.2 Design Ideas

Fig2.Photovoltaic Layout in Tangquan Pool Service Area

Use vacant resources such as building roofs and parking sheds in expressway service areas (toll stations),passenger and freight terminals,rationally layout distributed photovoltaic power generation facilities,and create a ＂carport photovoltaic+rooftop photovoltaic＂ power generation model;Supporting the construction of fast charging piles (stations),promoting ＂solar energy storage and charging integration＂ intelligent charging facilities,reasonably matching electricity demand,and improving energy utilization,see Fig2.

The annual peak sunshine hours in the project area are about 1,460 hours,and the total annual horizontal radiation is about 4,800MJ/m2.The design scale of 1,000kwp distributed photovoltaic power generation project,all panel arrays are installed on the roof of the building,the project service area and toll station building roof are facing south,the building interval is large,there is no obstruction from each other,the surrounding is empty,there is no high building blocking,the local solar energy resources are richer,the sunshine time is long,suitable for the installation of solar photovoltaic power plant projects.

Photovoltaic power generation is under the action of photovolt effect,the use of solar cells array of solar cells to absorb light energy,at both ends of the solar cell to generate electromotive force,the light energy into electrical energy,solar cells are generally silicon cells are energy conversion devices,the average photoelectric conversion efficiency between 17% and 19.6%.

2.3 Concept of Multi-Energy Complementary System

In view of the weak concept of multi-energy complementarity in the service area,the low efficiency of the comprehensive energy system,but the diverse energy demand,including providing basic service functions such as winter heating,summer cooling,daily power supply and hot water to social drivers and service area employees,huge energy demand,high carbon emissions and other problems,according to the characteristics of heating demand in Tangquan Pool service area,combined with local environmental protection requirements,fully considering capital investment and service area construction planning,it is planned to establish a multi-energy complementary AC/DC flexible microgrid system in this project.Through the mutual complementarity and cascade utilization of multiple energy sources,improve the comprehensive utilization efficiency of the energy system,form a rich clean and lowcarbon energy supply structure system,realize the deep integration between clean energy,and carry out multienergy complementarity and optimal dispatch of various distributed energy systems in the service area to create a low-carbon service area.

Through multi-energy complementarity,the efficient and high-proportion consumption and conversion of renewable energy such as solar energy can be realized.Solar power supply,air energy or geothermal energy heating (cooling),and auxiliary heat storage,power storage and other technologies to achieve the integration of cold,heat and electricity.The use of air energy or geothermal energy heating (cold),can absorb photovoltaic power generation,in the photovoltaic power generation is large,can use heat storage technology to further absorb electricity,photovoltaic power generation is insufficient or at night,heat storage device can be used to release heat,so as to achieve low energy consumption heating at night,enhance the connection between various energy sources,further improve the energy utilization rate of end users,maximize the local consumption of renewable energy,improve the energy utilization,economy and stability of the energy system in the service area,and reduce the external energy demand of the service area.

3 Dis tribu ted Photovol taic Power Generation Applications in Service Areas

3.1 Clean Energy Recycling

The operation of the service area requires heating and providing domestic hot water,which consumes a lot of energy.The use of cleaning can ensure the use of the function,and the source recycling in the whole life cycle,to maximize energy saving and carbon reduction in the construction process and operation and maintenance stage.

Fig3.The Original Appearance of Tangquan Pool Service Area

In view of the hot spring resources in the Tangquan Pond service area (see Figure 3),for the first time in the service area,the hot spring water source heat pump technology was used to make full use of geothermal energy to provide heating energy for the service area.The cold and heat source adopts screw water source (hot spring) heat pump unit,which absorbs heat from groundwater in winter and provides 45/40°C hot water in winter;In summer,the heat of the system is released to the reservoir,and 7/12°C cold water is provided in summer,and the fan coil/air conditioning unit+fresh air system is used at the end,see Fig4.

Fig4.Design of Water Source (Hot Spring) Heat Pump

The operation mode of photovoltaic power generation is based on the solar module array as the absorption factor,under the condition of solar radiation,the absorbed and stored solar energy is converted into output electric energy,and then the grid-connected inverter is inverted into alternating current supply service area power equipment,and the excess or insufficient power is adjusted by connecting to the power grid to complete the complete power consumption,replenishment and storage.In the process of service area construction,photovoltaic building integration can be considered,and the photovoltaic power generation system and the building are designed,constructed and put into use at the same time,such as using photovoltaic modules to make the entire roof,exterior wall and glass curtain wall of the building,installing solar photovoltaic sheds in the parking lot,and using photoelectric complementary energy supply for field lighting.

Fig5.Process of Photovoltaic Power Generation System in Service Area

3.2 Calculation of Emission Reduction and Carbon Reduction in Tangquan Pool Service Area

3.3.1 The calculation for power generation

The calculation formula for power generation is as follows：Ep=HA×A×ni×K

Wherein

Ep: On-grid power generation (kwh)

HA: Total horizontal solar irradiation (kW·h/m2,peak hours)

A: Solar module installation area

ni: Module conversion efficiency

K: Integrated efficiency factor

In particular,HA is temporarily based on the latitude and longitude of Zhengzhou.The conversion efficiency is calculated as a specification minimum of 17%.The overall efficiency is 0.75～0.85 according to the specification.The size specifications of solar photovoltaic panels are not fixed,considering the installation angle,the size of the solar panels and other factors,the annual power generation of photovoltaic panels per unit area is about 180kWh/m2,and the annual power generation per unit site area can be 150kWh/m2.

3.3.2 Calculation of emission reductions and savings

The CO2emission reduction of 1kWh photovoltaic power generation is not fixed,and the higher the proportion of new energy in the grid,the lower the CO2emission reduction value.The corresponding emission reduction amount is shown in Table 1,and the carbon emission reduction and energy-saving amount after the installation of the photovoltaic power generation system in the Tangquan Pool service area are shown in Tab2.

Tab1.Quantity of Emission Reductions When the Emission Reduction Factor is A Unit Value

Tab2.Carbon Emissions and Energy Savings in Tangquan Pool Service Area

4.Conclusion

The book Limits to Growth concludes that the human footprint has excessively affected the natural environment,that the self-healing capacity of ecosystems is already unsustainable,and that if the current population growth rate and resource consumption rate remain unchanged,the carrying capacity of the earth will reach its limit,calling for a shift from extreme growth to sustainable growth.

Therefore,as a key project demonstration project of new infrastructure construction in the field of transportation,the photovoltaic power generation system is set up in the Tangquan Pool service area and each station along the project line by using its own favorable conditions,improving the contradiction between ecological balance and economic development by adjusting the energy structure,responding to the call of the state to vigorously develop new energy,making full use of the site resources in the service area,insisting on energy conservation,taking energy conservation as the primary way to reduce carbon,improving the efficiency of traditional energy utilization,and increasing the proportion of clean energy.It can effectively reduce the loss of traditional fossil energy,protect the ecological environment,provide technical support for the implementation of the concept of green highway,and build an expressway with ＂energy saving,resource-saving,environmental friendliness,smooth and durable＂,achieving sustainable development and greater social benefits,at the same time,it can also save electricity costs every year,contributing to the construction of a conservation-oriented society.