**1. Introduction**

Strategic objectives were proposed during the 2015 United Nations Climate Conference in Paris which aimed to control the average global temperature within 2 ◦C of pre-industrial levels and make substantial effort to control temperature increases within 1.5 ◦C to achieve a peak of global greenhouse gas emissions (GHGs) as soon as possible, and achieve net-zero GHGs during the second half of this century [1].

Therefore, a series of policies have been proposed by countries to achieve carbon neutrality by 2050. For example, the European Union (EU) proposed that it would be carbon neutral by 2050 and hence released "*The European Green Deal*" in 2019 during the United Nations Climate Change Conference, which details key policies and core technologies in essential areas that are to be developed and the release of eight major goals [1,2]. The U.S. House of Representatives published "*The Congressional Action Plan for a Clean Energy Economy and a Healthy, Resilient, and Just America*" to promote the U.S. to achieve net-zero carbon emissions by 2050 [3]. Japan issued "*The Green Growth Strategy*", which introduced the country's goal to be carbon neutral by 2050 and proposed specific development goals and essential development tasks for core industries [4].

**Citation:** Xu, X.; Wang, Y.; Ruan, Y.; Wang, J.; Ge, K.; Zhang, Y.; Jin, H. Integrated Energy Planning for Near-Zero Carbon Emission Demonstration District in Urban Areas: A Case Study of Meishan District in Ningbo, China. *Energies* **2022**, *15*, 874. https://doi.org/ 10.3390/en15030874

Academic Editors: Michal Cehlar and Sergey Zhironkin

Received: 29 November 2021 Accepted: 19 January 2022 Published: 25 January 2022

**Publisher's Note:** MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

**Copyright:** © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

In order to contribute to the net-zero GHGs, China announced that peak CO<sup>2</sup> emissions will be achieved by 2030 and that the nation will become as carbon neutral as possible by 2060 [5]. Additionally, tens of Chinese policies related to the reduction in carbon emissions, renewable energy, the electricity market, energy storage, etc., have been promulgated by various management departments from 2020 to 2021. One of these policies is called "*Opinions of the Central Committee and the State Council on the complete, accurate and comprehensive implementation of the new development concept to achieve carbon peaking and carbon neutral*". The importance of energy planning is stressed by this policy. It is indicated that the carbon-neutral district is reaching the carbon emission limit rather than completely zero carbon emission. In the meantime, the requirements for both the supply and demand sides, as well as for multiple fields, such as energy, construction, industry, and transportation, need to be coordinated and put forward to achieve carbon neutrality [6]. Moreover, the Top Ten Actions for Carbon Peaking were announced in another Chinese policy called the "*Carbon Peaking Action Plan by 2030*", which aim to promote peak carbon emissions by 2030 [7].

Cities and provinces in China are projected to reach peak CO<sup>2</sup> emission between 2020 and 2030, while some relatively developed cities, such as Beijing, Zhenjiang, Shenzhen, etc., were projected to reach peak CO<sup>2</sup> emissions before 2020 [8].

The definition of CO<sup>2</sup> emission is clarified by IPCC and is defined is the sum of the GHGs that are converted into equivalent CO<sup>2</sup> emissions by the indexes of global warming potential (GWP), global temperature potential (GTP), radiative forcing equivalence potential, etc. [9]. However, there are various definitions of CO<sup>2</sup> emissions when defining emission targets related to carbon neutrality among countries [10]. In most western and in Asian countries, such as Demark, Slovakia, Chile, Switzerland, Portugal, Canada, the United Kingdom (UK), Singapore, Germany, Sweden, France, Finland, Japan, etc., CO<sup>2</sup> emissions are defined as GHGs. CO2, CH4, and N2O emissions are defined as CO<sup>2</sup> emissions in Bhutan and Uruguay. However, the definition in China and in many other countries is not clear. In this paper, CO<sup>2</sup> emissions refer to the GHGs in equivalent amounts of CO<sup>2</sup> based on GWP, including the emissions from fossil fuel combustions caused by transportation, electricity generation, manufacturing, building operations, etc.

Cai et al. [11] indicate that increases in carbon emissions are mainly driven by the population. In addition, over 90% of the total CO<sup>2</sup> emission in China are from urban areas [8]. This means that reducing CO<sup>2</sup> emissions in urban areas is significant for the total carbon reduction in the entire country, and conducting near-zero carbon emission programs is one of the current strategies in China that is being implemented to reduce carbon emissions in urban areas.

The Near-Zero Carbon Emission Demonstration District (NCEDD) project was first proposed in the China's 13th Five-Year Plan. This project is one of the 12 projects of the 13th Five-Year Plan and has caused widespread concern in the community. Moreover, the 13th Five-Year Plan proposed that GHG control measures in mature areas, which are subject to restricted and prohibited development, ecological functional areas, industrial mining areas and towns, etc., should be selected to carry out the NCEDD project and that 50 demonstration projects should be built by 2020.

In order to carry out the NCEDD, researchers, such as the IPCC, have mainly discussed near-zero carbon emissions in terms of its connotations. The IPCC indicates that carbon neutrality or net-zero CO<sup>2</sup> emissions are achieved when annual CO<sup>2</sup> emissions are considered to be balanced by decarburization technologies [9]. Near-zero carbon emissions are defined as being achieved when the net carbon emissions are approaching zero in a specific area. The relationship among near-zero carbon emissions, low carbon emissions, and zero carbon emissions is shown in Figure 1. Zero carbon emissions is the final objective for low-carbon community construction, while low carbon emissions and zero carbon emissions are necessary in the process to achieve zero carbon emissions. The net carbon emissions of a specific district can be decreased to zero gradually by reducing carbon

*Energies* **2022**, *15*, x FOR PEER REVIEW 3 of 28

emissions from the supply, contributing to zero carbon energy, etc. Moreover, near-zero carbon emissions refer to contexts that are approaching zero carbon emission situations. zero carbon emissions refer to contexts that are approaching zero carbon emission situa-

carbon emissions of a specific district can be decreased to zero gradually by reducing carbon emissions from the supply, contributing to zero carbon energy, etc. Moreover, near-

**Figure 1.** The relationship among near-zero carbon emissions, low carbon emissions, and zero carbon emissions. **Figure 1.** The relationship among near-zero carbon emissions, low carbon emissions, and zero carbon emissions.

The definition of an NCEDD can be explained based on the meaning of near-zero carbon emissions. Demonstration districts represent typical districts that are developed and constructed in advance. The development mode can play a demonstration role, and the experience can be replicated and promoted. Li et al. [12] define NCEDDs with nearzero carbon emission as follows: A typical district where the objective net carbon emissions approaching zero is achieved using approaches that reduce source carbon emissions, increase carbon sequestration, or contribute zero carbon energy, etc., within the boundaries of the county's (county-level city/district) administrative divisions and where the carbon-emission-reducing methods are replicable and can be promoted. Furthermore, two quantitative indexes are proposed for NCEDDs and are as follows: (1) It is possible for the total net carbon emissions to reach levels closer to zero by offsetting source carbon emissions and carbon sequestration or by offsetting source carbon emissions and by contrib-The definition of an NCEDD can be explained based on the meaning of near-zero carbon emissions. Demonstration districts represent typical districts that are developed and constructed in advance. The development mode can play a demonstration role, and the experience can be replicated and promoted. Li et al. [12] define NCEDDs with near-zero carbon emission as follows: A typical district where the objective net carbon emissions approaching zero is achieved using approaches that reduce source carbon emissions, increase carbon sequestration, or contribute zero carbon energy, etc., within the boundaries of the county's (county-level city/district) administrative divisions and where the carbon-emission-reducing methods are replicable and can be promoted. Furthermore, two quantitative indexes are proposed for NCEDDs and are as follows: (1) It is possible for the total net carbon emissions to reach levels closer to zero by offsetting source carbon emissions and carbon sequestration or by offsetting source carbon emissions and by contributing zero carbon energy; (2) absolute carbon emissions reach their peak value. These quantitative indexes are also important integrated energy planning objectives for NCEDDs.

uting zero carbon energy; (2) absolute carbon emissions reach their peak value. These quantitative indexes are also important integrated energy planning objectives for NCEDDs. Liu [13] concludes four types of NCEDDs. The first type is 100% renewable energy demonstration districts, which are applicable to less developed areas with plentiful renewable energy resources. The second type is carbon-neutral demonstration districts, which are applicable for scenic areas with large amounts of forests and pastoral areas. The third type of NCEDD is partial demonstration in the industry, for example, near-zero carbon emission buildings. The fourth type of NCEDD is low carbon emission upgrades, which is further decarburized on the basis of current low carbon emission pilot projects. Liu [13] concludes four types of NCEDDs. The first type is 100% renewable energy demonstration districts, which are applicable to less developed areas with plentiful renewable energy resources. The second type is carbon-neutral demonstration districts, which are applicable for scenic areas with large amounts of forests and pastoral areas. The third type of NCEDD is partial demonstration in the industry, for example, near-zero carbon emission buildings. The fourth type of NCEDD is low carbon emission upgrades, which is further decarburized on the basis of current low carbon emission pilot projects. The first and second types are constrained by regional and resource issues, and they are not able to be promoted in developed urban areas. The third and fourth types only consider near-zero carbon emissions in a narrow sense. It is necessary to determine how to build NCEDDs in developed urban areas.

The first and second types are constrained by regional and resource issues, and they are not able to be promoted in developed urban areas. The third and fourth types only consider near-zero carbon emissions in a narrow sense. It is necessary to determine how to build NCEDDs in developed urban areas. Reasonable district-integrated energy planning is an important part of constructing Reasonable district-integrated energy planning is an important part of constructing urban NCEDDs. Recently, the commonly used methods for energy planning are demandside energy planning and supply-side energy planning. In Chinese urban planning systems, urban power planning, gas planning, and centralized cooling and heating planning mostly belong to supply-side energy planning, i.e., top-down planning. However, demand-side energy planning starts from the demand side, pays attention to the effective integration

urban NCEDDs. Recently, the commonly used methods for energy planning are demand-

tems, urban power planning, gas planning, and centralized cooling and heating planning

and reasonable application of various energy resources in urban areas, and is a bottom-up process. In recent years, demand-side energy planning has been utilized more and more often in district-integrated energy planning.

Recently, there has been increasing amounts of research into demand-side planning, a large amount of which has been conducted by Long [14–17], Jeli´c [18], Wang [19], and Yu [20] et al. Most of these researches proposed reducing energy demand, utilizing renewable energy sources instead of fossil fuels, and capturing and storing carbon (CCS). These are solutions also indicated by Khalilpour [21] as specific technical approaches for the reduction in carbon emissions. However, developed urban areas lack carbon sequestration resources, such as forests and pastoral areas, which makes it even more difficult for them to achieve near-zero carbon emissions. Apart from reducing energy demand and applying renewable energy, Dobbelsteen et al. [22] proposed seeking energy synergy rather than CCS in urban energy planning. In addition, energy cascade utilization, the reuse of waste heating, energy storage, etc., are ways in which energy synergy can be implemented, which can provide heating and cooling network connections at different temperature levels.

In existing research, there is generally no clear planning method for district energy planning and few implementation conditions for energy schemes [23–27]. There have been numerous limitations in the research that has been carried out recently. The Shenzhen Academy of Building Research Co., Ltd. [23] conducted a green and ecological district in Ya'an by energy demand forecasting and energy resources analysis. The renewable energy and heat pump systems are planned to take place after evaluation. Cheng et al. [24] proposed four available energy station schemes with integrated energy utilization and energy micro-grid in a northern district. Tang et al. [25] developed energy schemes for a district in Guilin by determining planning objectives and analyzing energy demand and energy resources. The Tianjin Architectural Design Institute et al. [26] utilized a planning method that consisted of project investigation, demand forecasting, the proposal of energy schemes, the evaluation and comparison of energy schemes, and the determination of recommended schemes. The energy schemes for the university park in Tianjin were proposed and determined by the HVAC, electrical, water supply, and drainage energy consumption sectors. Although this method is relatively clear, it is only suitable for building sector districts rather than industrial and traffic sectors. Zhejiang Zheneng Energy Service Co., Ltd. et al. [27] proposed an integrated energy planning scheme for a district called Xiangbao in Ningbo. The distributed energy stations are planned for buildings and industries. Additionally, special planning for solar energy, electricity, water source, and utility tunnels is proposed based on local conditions. However, there are limitations for the above researches in terms of the absence of clear planning methods, planning objectives, and integrated and implementable energy schemes. The limitations of the above mentioned researches are listed in Table 1.


**Table 1.** The limitations of recent research into district energy planning.

"•" means the condition that is invloved in the district planning.

In this paper, a case study of the Meishan International Near-Zero Carbon Emission Demonstration District (MINCEDD) was investigated in order to propose an integrated energy planning scheme for this district. Moreover, a three-step planning method for the planning of NCEDDs was proposed and includes planning objectives, approaches, and strategies. After that, the planning results were analyzed and compared with respect to the indexes of renewable energy and CO<sup>2</sup> reduction.

#### **2. Methods and Algorithms**

#### *2.1. The Three-Step Planning Method*

A three-step planning method for NCEDD development is proposed that determines the planning objectives, planning strategies, and planning approaches. Firstly, the planning objectives are determined by focusing on targets such as CO<sup>2</sup> reduction, renewable energy utilization, etc. After that, the planning strategies are formed as the overall principles of the planning approaches, which consist of reducing energy demand, applying renewable energy based on local resource conditions, and improving integrated energy efficiency through means such as thoroughly utilizing waste heat on the demand side. Finally, the planning approaches are proposed based on the objectives and on the local conditions affecting access to natural resources, current and planned building construction, traffic and industry, etc., and can be categorized into the demand-side, supply-side, grid-side, and storage-side approaches, according to the energy application segment.

#### 2.1.1. Determining the Planning Objectives

The objectives should be determined to satisfy the NCEDD target as well as to be appropriate the local conditions of the district. Therefore, the research team investigated local energy supply companies, local governments, local factories, etc. to thoroughly understand the current conditions for renewable energy utilization and potential, the electricity supply, industrial energy consumption, and waste energy potential, etc.

The research team evaluated and researched the energy utilization potential and advantage of the district by analyzing the current energy supply, energy consumption, and renewable and waste energy potential. After that, the NCEDD objectives were determined with respect to the indexes of renewable energy utilization and CO<sup>2</sup> emission reduction.

#### 2.1.2. Establishing the Planning Strategies

In order to the achieve the objectives that were previously determined, the planning strategies were established from the aspects of reducing energy demand, improving energy efficiency, and utilizing both waste heat and renewable energy. The strategies must not only be established according to the objectives but should also be adapted to the local conditions of the planned district.

#### 2.1.3. Proposing the Planning Approaches

Planning approaches are based on "demand-supply-grid-storage", which means reducing energy demand on the demand side, utilizing renewable energy on the supply side, and improving energy interconnection and peak load shifting on the grid and storage sides so as to achieve the objectives of the MINCEDD.

#### *2.2. The Calculation Algorithms of Planning Indexes*

After applying the three-step planning method, including the objectives, strategies, and approaches, indexes with respect to renewable energy utilization and CO<sup>2</sup> emission reduction are proposed and summarized in Table 2. The indexes were evaluated by analyzing and comparing other similar planned districts. The advancement and feasibility of the planning scheme based on the three-step planning method can be proven after the evaluation.

#### 2.2.1. Proportion of Renewable Energy to Primary Energy

In order to explain the definition of the RE/PE index, the algorithm of this index is introduced followed by its explanation in this sub-section.

Algorithm: Total renewable energy consumption (tce) ÷ Total primary energy consumption (tce) × 100%


**Table 2.** The summary of major planning indexes.

Explanation: Renewable energy refers to the energy rather than fossil fuels and includes wind energy, solar energy, water energy, biomass, geothermal energy, ocean energy, etc. According to the second provision of the "*China National Renewable Energy Law*" [28], renewable energy power mainly consists of solar PV, wind power, biomass power, etc. Primary energy refers to the energy resources that exist in nature without processing and conversion, also known as natural energy, such as coal, oil, natural gas, hydropower, etc.

Total energy consumption is the total amount of annual energy consumed on the demand side in the planned district. RE/PE is the amount of total annual consumed renewable energy divided by the total annual consumed primary energy in the planned district.

#### 2.2.2. Proportion of Renewable Power to Total Power Consumption

In order to explain the definition of the RP/PC index, the algorithm for this index is introduced followed by its explanation in this sub-section.

Algorithm: Renewable energy power generation (kWh) ÷ District total power consumption (kWh) × 100%

Explanation: Power generation refers to energy generation on the supply side. The meaning of renewable power is the power generated from the renewable energy that is explained in Section 2.2.1. RP/PC is the total annual renewable power generated divided by the total annual power consumed in the planned district.

## 2.2.3. CO<sup>2</sup> Emission Reduction

In order to explain the definition of the CO<sup>2</sup> emission reduction index, the algorithm of this index is introduced followed by its explanation in this sub-section.

Algorithm: (CO<sup>2</sup> emission caused by conventional energy supply − CO<sup>2</sup> emission caused by near-zero carbon emission energy supply) ÷ CO<sup>2</sup> emission caused by conventional energy supply × 100%

Explanation: Conventional energy is the primary energy that has been mass-produced and widely used, such as coal, oil, natural gas, etc. Zero-carbon emission energy is the energy that is generated and consumed without creating carbon emissions, such as solar energy, wind energy, ocean energy, geothermal energy, etc. The near-zero carbon emission energy supply refers to the combination of conventional and zero-carbon emission energy supply in planned districts, which leads to the overall near-zero carbon emission effect.

The three-step planning method process is shown in Figure 2.

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**Figure 2.** The three-step planning method process. **Figure 2.** The three-step planning method process. **3. Present Situation of the Planning District** 

#### **3. Present Situation of the Planning District 3. Present Situation of the Planning District** *3.1. The Planning Area and Planning Period*

*3.1. The Planning Area and Planning Period 3.1. The Planning Area and Planning Period* The MINCEDD planning area, which is located in Ningbo, Zhejiang province, is 333

The MINCEDD planning area, which is located in Ningbo, Zhejiang province, is 333 km2 and includes Meishan Island in the Beilun area, Chunxiao Street, and Baifeng Town. The planning area is shown in Figure 3. The MINCEDD planning area, which is located in Ningbo, Zhejiang province, is 333 km<sup>2</sup> and includes Meishan Island in the Beilun area, Chunxiao Street, and Baifeng Town. The planning area is shown in Figure 3. km2 and includes Meishan Island in the Beilun area, Chunxiao Street, and Baifeng Town. The planning area is shown in Figure 3.

that make up a total land area of 43.49 km2 and includes Financial Town, the Menhu Area, **Figure 3.** The MINCEDD planning area. **Figure 3.** The MINCEDD planning area.

Figure 4).

Figure 4). According to the regulatory plans, the main planning area comprises six core areas that make up a total land area of 43.49 km2 and includes Financial Town, the Menhu Area, the Industry Area, the Bonded Area, the East Area, and the Li'ao Area (as is shown in According to the regulatory plans, the main planning area comprises six core areas that make up a total land area of 43.49 km<sup>2</sup> and includes Financial Town, the Menhu Area, the Industry Area, the Bonded Area, the East Area, and the Li'ao Area (as is shown in Figure 4).

the Industry Area, the Bonded Area, the East Area, and the Li'ao Area (as is shown in

**Figure 4.** The planning areas. **Figure 4.** The planning areas. **Figure 4.** The planning areas.

The planning period is from 2020 to 2050, with mid-term planning taking place from 2020 to 2030 and long-term planning taking place from 2030 to 2050. The planning period is from 2020 to 2050, with mid-term planning taking place from 2020 to 2030 and long-term planning taking place from 2030 to 2050. The planning period is from 2020 to 2050, with mid-term planning taking place from 2020 to 2030 and long-term planning taking place from 2030 to 2050.

#### *3.2. Local Energy Resources 3.2. Local Energy Resources 3.2. Local Energy Resources*

The MINCEDD belongs to the subtropical monsoon climate zone (see Figure 5) [29] and contains abundant renewable resources and clean energy. In order to appropriately propose energy planning schemes based on local conditions, energy resources, including solar energy, wind energy, biomass energy, liquefied natural gas (LNG) cold energy, and hydrogen energy, are each analyzed and evaluated in the following. The MINCEDD belongs to the subtropical monsoon climate zone (see Figure 5) [29] and contains abundant renewable resources and clean energy. In order to appropriately propose energy planning schemes based on local conditions, energy resources, including solar energy, wind energy, biomass energy, liquefied natural gas (LNG) cold energy, and hydrogen energy, are each analyzed and evaluated in the following. The MINCEDD belongs to the subtropical monsoon climate zone (see Figure 5) [29] and contains abundant renewable resources and clean energy. In order to appropriately propose energy planning schemes based on local conditions, energy resources, including solar energy, wind energy, biomass energy, liquefied natural gas (LNG) cold energy, and hydrogen energy, are each analyzed and evaluated in the following.

**Figure 5.** Climate zone distribution of China. **Figure 5.** Climate zone distribution of China. **Figure 5.** Climate zone distribution of China.

#### 3.2.1. Solar Resource 3.2.1. Solar Resource 3.2.1. Solar Resource

Solar energy is one of the most competitive sources of renewable energy due to its abundance and clean operation. Total annual solar radiation of MINCEDD is greater than 4008 MJ/m2/a [30]. Solar energy is one of the most competitive sources of renewable energy due to its abundance and clean operation. Total annual solar radiation of MINCEDD is greater than 4008 MJ/m2/a [30]. Solar energy is one of the most competitive sources of renewable energy due to its abundance and clean operation. Total annual solar radiation of MINCEDD is greater than 4008 MJ/m2/a [30].

#### 3.2.2. Wind Resource 3.2.2. Wind Resource

Wind resources are relatively rich in the MINCEDD [31]. Wind resources are simulated using computational fluid dynamics (CFD) numerical software. The simulation results show that in the winter and summer, the dominant wind directions are northwest and southeast, respectively. In addition, the dominant wind speed is about 7.48 m/s in winter and 7.95 m/s in summer and occurs at the height of 80 m. The wind speed distribution map at different heights in the planning area is shown in Figure 6. Wind resources are relatively rich in the MINCEDD [31]. Wind resources are simulated using computational fluid dynamics (CFD) numerical software. The simulation results show that in the winter and summer, the dominant wind directions are northwest and southeast, respectively. In addition, the dominant wind speed is about 7.48 m/s in winter and 7.95 m/s in summer and occurs at the height of 80 m. The wind speed distribution map at different heights in the planning area is shown in Figure 6.

**Figure 6.** Wind speed chart at different heights. **Figure 6.** Wind speed chart at different heights.

#### 3.2.3. Hydrogen Energy Resource 3.2.3. Hydrogen Energy Resource

Ningbo is a city with a large amount of industrial by-product hydrogen, which is mostly expulsed from the Daxie Industrial Park. According to TrendBank statistics, Ningbo can supply about 72 kt/yr of by-product hydrogen, which indicates the large planning potential of byproduct hydrogen from the industry sector. Moreover, the purity of industrial by-product hydrogen from Donghua Energy and from Wanhua Chlor-Alkali is 99.99% based on site investigations. Existing hydrogen by-product production is detailed in Table 3. Ningbo is a city with a large amount of industrial by-product hydrogen, which is mostly expulsed from the Daxie Industrial Park. According to TrendBank statistics, Ningbo can supply about 72 kt/yr of by-product hydrogen, which indicates the large planning potential of by-product hydrogen from the industry sector. Moreover, the purity of industrial by-product hydrogen from Donghua Energy and from Wanhua Chlor-Alkali is 99.99% based on site investigations. Existing hydrogen by-product production is detailed in Table 3.

**Table 3.** Industrial by-product hydrogen in Ningbo area. **Table 3.** Industrial by-product hydrogen in Ningbo area.


Total 443,700

#### 3.2.4. LNG Cold Energy Resource 3.2.4. LNG Cold Energy Resource

An LNG receiving station that belongs to Zhonghai Ningbo Liquefied Natural Gas Co., Ltd. is located at the northeast end of the planning area. The external transmission capacity of the LNG receiving station is 7 million tons per year. Currently, only 400 ktons of LNG per year is used for cold energy air separation operations, while most of the remaining cold energy is released into the sea water. Hence, there is large application potential in which the remaining cold energy can be used. The LNG receiving station location is shown in Figure 7. An LNG receiving station that belongs to Zhonghai Ningbo Liquefied Natural Gas Co., Ltd. is located at the northeast end of the planning area. The external transmission capacity of the LNG receiving station is 7 million tons per year. Currently, only 400 ktons of LNG per year is used for cold energy air separation operations, while most of the remaining cold energy is released into the sea water. Hence, there is large application potential in which the remaining cold energy can be used. The LNG receiving station location is shown in Figure 7.

**Figure 7.** Geographical location of the LNG receiving station. **Figure 7.** Geographical location of the LNG receiving station.

#### 3.2.5. Other Resources 3.2.5. Other Resources

The biomass resources and low-grade heat sources in the planning area were investigated and evaluated. The existing biomass power plants cover all biomass resources in the planned district and part of the biomass resources beyond the MINCEDD in Ningbo (including domestic waste). There is additional capacity that can be used by the MINCEDD biomass power plant in the future even though the capacity of the plant will maintain its status due to garbage odor concerns in the selected location. In addition, a sewage treatment plant with a daily treatment capacity of 35,000 tons will be built in the near future. According to the progress being made in the construction of the sewage plant and the surrounding users, it is proposed that a small-scale sewage source heat pump system can be developed by the MINCEDD in the future. Apart from biomass and sewage source, low-grade heat sources, groundwater sources, soil sources, and seawater sources are not suitable for exploitation due to the environmental and policy constraints. The biomass resources and low-grade heat sources in the planning area were investigated and evaluated. The existing biomass power plants cover all biomass resources in the planned district and part of the biomass resources beyond the MINCEDD in Ningbo (including domestic waste). There is additional capacity that can be used by the MINCEDD biomass power plant in the future even though the capacity of the plant will maintain its status due to garbage odor concerns in the selected location. In addition, a sewage treatment plant with a daily treatment capacity of 35,000 tons will be built in the near future. According to the progress being made in the construction of the sewage plant and the surrounding users, it is proposed that a small-scale sewage source heat pump system can be developed by the MINCEDD in the future. Apart from biomass and sewage source, low-grade heat sources, groundwater sources, soil sources, and seawater sources are not suitable for exploitation due to the environmental and policy constraints.

#### *3.3. Current Energy Consumption*

*3.3. Current Energy Consumption*  The total energy consumption in the MINCEDD was about 318 ktce in 2017 and includes 106.9 ktce of building consumption, 177.3 ktce of industry consumption, and 34.2 ktce of traffic consumption. The building, industry, and traffic sectors account for 33.5%, The total energy consumption in the MINCEDD was about 318 ktce in 2017 and includes 106.9 ktce of building consumption, 177.3 ktce of industry consumption, and 34.2 ktce of traffic consumption. The building, industry, and traffic sectors account for 33.5%, 55.7%, and 10.8% of the total energy consumption, respectively.

55.7%, and 10.8% of the total energy consumption, respectively. In addition, there are 235.8 ktce of primary energy that are consumed by electricity, which is 74.1% of the total primary energy consumption. The natural gas consumption is 27.5 ktce and fossil fuel (incl. coal and oil) consumption is 55 ktce, representing 8.6% and 17.3% of total primary energy, respectively. Figure 8 illustrates the energy consumption In addition, there are 235.8 ktce of primary energy that are consumed by electricity, which is 74.1% of the total primary energy consumption. The natural gas consumption is 27.5 ktce and fossil fuel (incl. coal and oil) consumption is 55 ktce, representing 8.6% and 17.3% of total primary energy, respectively. Figure 8 illustrates the energy consumption and percentages of different energy sectors and energy sources [32].

and percentages of different energy sectors and energy sources [32].

**Figure 8.** The composition of primary energy consumption. **Figure 8.** The composition of primary energy consumption.

#### **4. The Integrated Energy Planning Scheme 4. The Integrated Energy Planning Scheme**

#### *4.1. The Planning Objectives*

*4.1. The Planning Objectives*  The primary energy consumption is 318 ktce in 2017, and the energy intensity per unit GDP is 0.15 tce/CNY. The integrated energy planning objectives for the MINCEDD were determined by taking NCEDD as a guide, planning based on the local population and GDP, integrating local energy resources and energy demand characteristics, and using the quantitative scenario analysis method [33]. The planning objectives are listed in The primary energy consumption is 318 ktce in 2017, and the energy intensity per unit GDP is 0.15 tce/CNY. The integrated energy planning objectives for the MINCEDD were determined by taking NCEDD as a guide, planning based on the local population and GDP, integrating local energy resources and energy demand characteristics, and using the quantitative scenario analysis method [33]. The planning objectives are listed in Table 4.

#### Table 4. **Table 4.** The planning objectives and index compliance.


#### CO2 emission reduction (ton) ≥750,000 ≥1,100,000 *4.2. The Planning Strategies*

green travel, etc.

#### *4.2. The Planning Strategies*  4.2.1. Reducing Energy Demand

4.2.1. Reducing Energy Demand The core of achieving the objective of near-zero carbon emissions is reducing energy The core of achieving the objective of near-zero carbon emissions is reducing energy consumption on the demand side and increasing the sources of the energy supply. Energy demands consist of building demand, industry demand, and traffic demand.

consumption on the demand side and increasing the sources of the energy supply. Energy demands consist of building demand, industry demand, and traffic demand. Building demand can be reduced by passive measures, which are as follows: (1) im-Building demand can be reduced by passive measures, which are as follows: (1) improving building envelope performance to reduce winter heating and summer cooling and (2) introducing natural ventilation to reduce the demand for cooling and heating during the transition seasons.

proving building envelope performance to reduce winter heating and summer cooling and (2) introducing natural ventilation to reduce the demand for cooling and heating during the transition seasons. Industry demand can be reduced by industrial restructuring, which is achieved by restricting and gradually eliminating high-energy-demand industries (i.e., energy con-Industry demand can be reduced by industrial restructuring, which is achieved by restricting and gradually eliminating high-energy-demand industries (i.e., energy consumption per unit output value higher than 0.07 kgce/CNY) and introducing high output with low-energy-consumption industries (i.e., energy consumption per unit output value lower than 0.015 kgce/CNY).

sumption per unit output value higher than 0.07 kgce/CNY) and introducing high output with low-energy-consumption industries (i.e., energy consumption per unit output value lower than 0.015 kgce/CNY). Traffic demand is reduced by transportation energy transformation and by changing the travel mode, for instance, restricting cars with high emissions, encouraging public and green travel, etc.

Traffic demand is reduced by transportation energy transformation and by changing the travel mode, for instance, restricting cars with high emissions, encouraging public and

#### 4.2.2. Improving Energy Efficiency and Utilizing Waste Heat

1. Improving energy efficiency of building sector:

In buildings, energy consumption mainly takes place through lighting, sockets, air conditioning, power system, and special equipment.

In terms of lighting, a building's energy consumption can be reduced by using LED lights, installing intelligent control, controlling the lighting by zones, etc.

The amount of energy consumed by a building in terms of air conditioning can be reduced by improving the energy efficiency of a system and equipment, such as heating/cooling units, boilers, pumps, fans, air handling units, etc.

The amount of energy that a building consumes in terms of its power system consists of the energy that is used by water pumps, elevators, etc. The energy efficiency measures for water pumps refers to the selection of high-efficiency and variable-frequency equipment. The energy efficiency measures for elevators are variable frequency, group controlling, etc.

Waste heat can be applied in the following ways. (1) Heat recovery on the air system side: Using a heat exchanger to recover the heat from exhaust air or fresh air so that the fresh air can be pre-heated or cooled and can reduce the energy for fresh air. (2) Units can recover condensation heat: The heat that is generated from cooling condensation water in the summer is recovered for domestic hot water heating to decrease the hot water heating energy, which has a significant energy-saving effect for buildings with a high demand for domestic hot water such as in-patient buildings and hotels. (3) Elevator energy feedback: The energy that is generated during elevator operation is given back to the power grid or to the micro power grid for reuse, which can save electricity consumption by about 30%.

2. Improving energy efficiency of industry sector:

First, the energy efficiencies of general equipment, such as boilers, motors, transformers, and air compressors, should be improved.

Second, heat recovery and cascade utilization are the major approaches for reusing industrial waste heat. This means the recovered heat is used for industrial processes or for heating the areas in the building. Most equipment, such as prime motors, heating furnaces, air compressors, annealing furnaces, VOC handling units, boilers, etc., only consume small amounts of heating energy. Recovering the remaining industrial heating energy for centralized heating can save primary energy, improve economic benefit, and reduce pollution.

#### 4.2.3. Utilizing Renewable Energy Adapted to Local Conditions

For urban areas, utilizing renewable energy that can be adapted to local conditions is the last guaranteed method through which near-zero carbon emissions can be achieved and is based on decreasing energy demand, improving energy efficiency, and using waste heat. This means providing zero-carbon emission energy supply, which is close to or is more than fossil fuel consumption.

Renewable energy consists of solar energy, wind energy, ocean energy, geothermal energy, etc. Distributed renewable energy is the best way to use renewable energy sources. This can be achieved, for example, by installing a solar photovoltaic system, wind turbines, etc., for buildings or in communities. High-percentage renewable power is consumed by cascade grid connection and energy storage to maintain the stability of the power grid.

#### *4.3. The Planning Approaches*

#### 4.3.1. Demand Side

1. Building Sector

The point and surface combination method is used for building sector energy demand reduction. From the point of view of the retrofitting objectives, energy conservation measures can be proposed for existing buildings, and design and construction requirements of energy conservation are proposed for new buildings. Therefore, all of the buildings will be constructed by conforming to the national ultra-low energy or near-zero energy building standards.

All existing buildings in MINCEDD will be retrofitted with energy conservation measures by 2030. Standards of ultra-low energy building are required for new buildings so that all new buildings conform to the current national standard "*Technical standard for nearly zero energy buildings*" [34] by 2030. Buildings built during 2030–2050 conform to the claims for the near-zero energy building standards determined by the current national standard "*Technical standard for nearly zero energy buildings*" [34]. The specific building performance parameters are listed in Table 5.


**Table 5.** Energy conservation measures for buildings.

<sup>1</sup> The pump energy efficiency is determined based on the related current national standard for pump.

In terms of surfaces, replicable projects for future community construction in accordance with "*Pilot Work Plan for Future Community Construction in Zhejiang Province*" are planned. The planning schemes for low-carbon communities are listed in Table 6.

**Table 6.** Low-carbon communities planning scheme.


After applying the above building energy conservation measures, the building energy demand forecasting results are listed in Tables 7 and 8. Scenario 1 refers to the conventional scenario for 2030, i.e., energy increases under the current rate. Scenarios 2 and 3 refer to the near-zero carbon emission scenarios for 2030 and 2050, respectively.

**Table 7.** Annual power consumption per building area for Scenarios 1–3 (unit: kWh/m<sup>2</sup> ).



**Table 8.** Annual power consumption for Scenarios 1–3 (unit: GWh).

#### 2. Traffic Sector

Green transportation and low-carbon travelling are recommended to reduce the amount of energy that is consumed by the traffic sector. In terms of "light-storage-charging" technology, there are seven power charging stations and five hydrogen refueling stations that are planned for green transportation. The vehicles will consume 100% of clean energy for public utilities, such as buses, taxi, and delivery vehicles, by 2030 and for private cars by 2050.

#### 3. Industry Sector

The industry energy conservation and low-carbon-emission objectives can be achieved by improving equipment efficiency and by integrating energy utilization and industrial restructuring. The introduction of industries with energy consumption per unit output below 0.20 tce/CNY into districts is encouraged. The evaluation and development recommendations for industrial structures are listed in Table 9. *Energies* **2022**, *15*, x FOR PEER REVIEW 15 of 28

#### 4.3.2. Supply Side 4.3.2. Supply Side

In order to achieve the target proportion of renewable energy and renewable power, renewable energy is the major source of energy on the supply side. The scheme for the supply side focuses on photovoltaic and wind power generation and the full utilization of LNG cold energy and hydrogen energy. The renewable energy capacity is planned according to demand forecast results, consuming maximum renewable power, avoiding reverse power transmission, and decreasing peak–valley difference fluctuations. The layout of the energy scheme for the supply side is shown in Figure 9. In order to achieve the target proportion of renewable energy and renewable power, renewable energy is the major source of energy on the supply side. The scheme for the supply side focuses on photovoltaic and wind power generation and the full utilization of LNG cold energy and hydrogen energy. The renewable energy capacity is planned according to demand forecast results, consuming maximum renewable power, avoiding reverse power transmission, and decreasing peak–valley difference fluctuations. The layout of the energy scheme for the supply side is shown in Figure 9.

To maximize the photovoltaic (PV) installation, it is suggested to make full use of a building's roof, façade, and structure to design building-integrated photovoltaics (BIPV). The maximum area of factory roofs (≥60% of roof area) and available civil building roofs (≥20% of roof area) are utilized to install solar photovoltaic systems. The capacity of in-

**Table 10.** PV layout plans for different types of buildings by 2030 (40 MW in existence).

**(m2) (%) (m2) (MW) (GWh)** 

**Table 11.** PV layout plans for different types of buildings by 2050 (40 MW in existence).

**(m2) (%) (m2) (MW) (GWh)** 

**Figure 9.** Source-side energy plan layout. **Figure 9.** Source-side energy plan layout.

buildings is detailed in Tables 10 and 11.

1. Solar Energy

**Building Type Roof Area Roof Usage Rate PV Area PV Capacity Power Generation** 

**Building Type Roof Area Roof Usage Rate PV Area PV Capacity Power Generation** 

Existing industry 3,217,000 60 1,930,200 193.0 193 Residential 332,000 20 66,500 6.6 7 Commercial Office 1,006,000 20 201,300 20.1 20

Existing industry 3,220,000 60 1,930,000 1,930,000 193 Residential 300,000 20 60,000 60,000 6 Commercial Office 910,000 20 183,000 183,000 18 Industry 4,070,000 60 2,441,000 2,441,000 244 Education 190,000 20 38,000 38,000 4 Warehouse 2,260,000 20 1,357,000 1,357,000 136 Total 10,950,000 / 6,009,000 6,009,000 601

*Energies* **2022**, *15*, 874


**Table 9.** The evaluation and development recommendations of industrial structure.

#### 1. Solar Energy

To maximize the photovoltaic (PV) installation, it is suggested to make full use of a building's roof, façade, and structure to design building-integrated photovoltaics (BIPV). The maximum area of factory roofs (≥60% of roof area) and available civil building roofs (≥20% of roof area) are utilized to install solar photovoltaic systems. The capacity of installed solar photovoltaic systems will increase to 600 MW by 2030 and will increase to 642 MW by 2050. The planning scheme for photovoltaic systems for different types of buildings is detailed in Tables 10 and 11.

**Table 10.** PV layout plans for different types of buildings by 2030 (40 MW in existence).


**Table 11.** PV layout plans for different types of buildings by 2050 (40 MW in existence).


#### 2. Wind Energy

Distributed onshore wind power and offshore wind power will be developed first. Then, centralized onshore wind power will be installed during the period of 2030~2050. The distributed wind power will be installed near factories and warehouses and will be more than 300 m away from residential areas. Offshore wind power will be installed away from channels and in the areas near the seacoast that are not sheltered. In addition, the installation of onshore wind power generation facilities on the ridge, where the wind resources are superior, is suggested. The wind capacities for different planning periods are shown in Table 12.

**Table 12.** The wind power capacity.


#### 3. Hydrogen energy

It is recommended that hydrogen energy is obtained from industrial by-products and hydrogen electrolysis devices that are powered by surplus renewable power.

There are five hydrogen refueling stations with a capacity of 500 kg/d that are planned according to integrated energy supply stations for the traffic sector. Two of them will be built in the integrated stations by 2030 in order to satisfy the hydrogen demands of buses, delivery vehicles, and transportation vehicles. The other three hydrogen refueling stations will be built by 2050 in order to satisfy the increasing demand for the use of hydrogen in the traffic sector in the future. Furthermore, the main applications are the construction of hydrogen refueling stations, household hydrogen fuel cells, hydrogen fuel vehicles, and trucks. Hydrogen will be partially mixed with natural gas and will used for cooking and heating in buildings in the long term. The overall utilization plan for hydrogen energy is shown in Figure 10. will be built in the integrated stations by 2030 in order to satisfy the hydrogen demands of buses, delivery vehicles, and transportation vehicles. The other three hydrogen refueling stations will be built by 2050 in order to satisfy the increasing demand for the use of hydrogen in the traffic sector in the future. Furthermore, the main applications are the construction of hydrogen refueling stations, household hydrogen fuel cells, hydrogen fuel vehicles, and trucks. Hydrogen will be partially mixed with natural gas and will used for cooking and heating in buildings in the long term. The overall utilization plan for hydrogen energy is shown in Figure 10.

Distributed onshore wind power and offshore wind power will be developed first.

Then, centralized onshore wind power will be installed during the period of 2030~2050. The distributed wind power will be installed near factories and warehouses and will be more than 300 m away from residential areas. Offshore wind power will be installed away from channels and in the areas near the seacoast that are not sheltered. In addition, the installation of onshore wind power generation facilities on the ridge, where the wind resources are superior, is suggested. The wind capacities for different planning periods are

**(MW)** 

Total 419 788

planned according to integrated energy supply stations for the traffic sector. Two of them

It is recommended that hydrogen energy is obtained from industrial by-products and

**Total Capacity of 2050 (MW)** 

**Type Total Capacity of 2030** 

Distributed wind power 66 131 Offshore wind power 258 337 Onshore wind power 95 (current condition) 320

hydrogen electrolysis devices that are powered by surplus renewable power.

*Energies* **2022**, *15*, x FOR PEER REVIEW 16 of 28

Industry 4,475,000 60 2,684,800 268.5 268 Education 207,000 20 41,300 4.1 4 Warehouse 2,487,000 20 1,492,200 149.2 149 Total 11,724,000 -- 6,416,000 641.5 641

2. Wind Energy

shown in Table 12.

3. Hydrogen energy

**Table 12.** The wind power capacity.

**Figure 10.** The overall utilization plan for hydrogen energy. **Figure 10.** The overall utilization plan for hydrogen energy.

#### 4. LNG cold energy

There is currently an LNG receiving station with a capacity of 7 Mton in the MINCEDD. Cold energy can be released and utilized after the LNG is gasified.

A cold energy cascade utilization industrial area that includes air separation, CO<sup>2</sup> liquefaction and dry ice manufacturing, medical refrigeration, and a data center is planned near the receiving station. Simultaneously, the natural gas that is produced after the gasification of LNG can be used for office buildings or small-scale commercial tri-generation system fuel cells in industrial parks and in surrounding areas. The layout proposed in the diagram of the industrial park is in Figure 11, and the LNG cold energy cascade utilization process is shown in Figure 12.

#### 4.3.3. Grid Side

The port, industry, city, transportation, urban energy grid, green transport charging grid, and port microgrid will be planned, all of which compose the green energy grid that is required for energy dispatch.

1. Urban Energy Grid

In the MINCEDD, renewable energy mainly includes wind energy and solar energy. The scheme through which renewable energy will be connected to the grid is illustrated in Figure 13.

There is currently an LNG receiving station with a capacity of 7 Mton in the

There is currently an LNG receiving station with a capacity of 7 Mton in the

A cold energy cascade utilization industrial area that includes air separation, CO2 liquefaction and dry ice manufacturing, medical refrigeration, and a data center is planned near the receiving station. Simultaneously, the natural gas that is produced after the gasification of LNG can be used for office buildings or small-scale commercial tri-generation system fuel cells in industrial parks and in surrounding areas. The layout proposed in the diagram of the industrial park is in Figure 11, and the LNG cold energy cas-

A cold energy cascade utilization industrial area that includes air separation, CO2 liquefaction and dry ice manufacturing, medical refrigeration, and a data center is planned near the receiving station. Simultaneously, the natural gas that is produced after the gasification of LNG can be used for office buildings or small-scale commercial tri-generation system fuel cells in industrial parks and in surrounding areas. The layout proposed in the diagram of the industrial park is in Figure 11, and the LNG cold energy cas-

MINCEDD. Cold energy can be released and utilized after the LNG is gasified.

MINCEDD. Cold energy can be released and utilized after the LNG is gasified.

*Energies* **2022**, *15*, x FOR PEER REVIEW 17 of 28

4. LNG cold energy

4. LNG cold energy

cade utilization process is shown in Figure 12.

cade utilization process is shown in Figure 12.

**Figure 11.** Schematic diagram of LNG cold energy industry layout. **Figure 11.** Schematic diagram of LNG cold energy industry layout. **Figure 11.** Schematic diagram of LNG cold energy industry layout.

**Figure 12.** LNG cold energy cascade utilization flow chart. **Figure 12.** LNG cold energy cascade utilization flow chart. **Figure 12.** LNG cold energy cascade utilization flow chart. in Figure 13.

**Figure 13.** The scheme through which renewable energy will be connected to the grid. **Figure 13.** The scheme through which renewable energy will be connected to the grid.

The voltage that is necessary for solar PV to connect is 0.4 kV. The voltage of the rest power is increased to 10 kV in order to continue consumption when the consuming ability under 0.4 kV is insufficient. Small and large amounts of wind power are preferentially connected to the 10 kV and 110 kV substations, respectively. This means that small and large amounts of wind power can be connected to the secondary side of the 220 kV sub-The voltage that is necessary for solar PV to connect is 0.4 kV. The voltage of the rest power is increased to 10 kV in order to continue consumption when the consuming ability under 0.4 kV is insufficient. Small and large amounts of wind power are preferentially connected to the 10 kV and 110 kV substations, respectively. This means that small and large amounts of wind power can be connected to the secondary side of the 220 kV substation,

station, the secondary side of the 110 kV substation, and the 10 kV switching station,

area and are suitable for connecting to the 0.4 kV voltage class, which is mainly intended

The charging infrastructures for electric vehicles (EV) and hydrogen energy vehicles are EV charging stations and hydrogen refueling stations, respectively, whose layouts

According to the principle of optimal land utilization and the use characteristics of EVs, it is suggested that charging stations should be built together with existing public service facilities. PV devices can be installed on the ceiling of the charging station to in-

A hydrogen refueling station will be built in the Li'ao area, which is located on the main roads and is in a location that is convenient for hydrogen vehicle users. Additionally, a hydrogen refueling station will be built in the port area during long-term planning.

constitute the green transport charging grid in Figure 14.

for self-use.

2. Green Transport Charging Grid

**Figure 14.** The layout of charging infrastructures.

crease the renewable energy use.

the secondary side of the 110 kV substation, and the 10 kV switching station, which is based on a different scale. PV facilities are widely distributed in the planning area and are suitable for connecting to the 0.4 kV voltage class, which is mainly intended for self-use. station, the secondary side of the 110 kV substation, and the 10 kV switching station, which is based on a different scale. PV facilities are widely distributed in the planning area and are suitable for connecting to the 0.4 kV voltage class, which is mainly intended for self-use.

The voltage that is necessary for solar PV to connect is 0.4 kV. The voltage of the rest power is increased to 10 kV in order to continue consumption when the consuming ability under 0.4 kV is insufficient. Small and large amounts of wind power are preferentially connected to the 10 kV and 110 kV substations, respectively. This means that small and large amounts of wind power can be connected to the secondary side of the 220 kV sub-

**Figure 13.** The scheme through which renewable energy will be connected to the grid.

In the MINCEDD, renewable energy mainly includes wind energy and solar energy. The scheme through which renewable energy will be connected to the grid is illustrated

2. Green Transport Charging Grid 2. Green Transport Charging Grid

The charging infrastructures for electric vehicles (EV) and hydrogen energy vehicles are EV charging stations and hydrogen refueling stations, respectively, whose layouts constitute the green transport charging grid in Figure 14. The charging infrastructures for electric vehicles (EV) and hydrogen energy vehicles are EV charging stations and hydrogen refueling stations, respectively, whose layouts constitute the green transport charging grid in Figure 14.

*Energies* **2022**, *15*, x FOR PEER REVIEW 18 of 28

in Figure 13.

According to the principle of optimal land utilization and the use characteristics of EVs, it is suggested that charging stations should be built together with existing public service facilities. PV devices can be installed on the ceiling of the charging station to increase the renewable energy use. According to the principle of optimal land utilization and the use characteristics of EVs, it is suggested that charging stations should be built together with existing public service facilities. PV devices can be installed on the ceiling of the charging station to increase the renewable energy use.

A hydrogen refueling station will be built in the Li'ao area, which is located on the main roads and is in a location that is convenient for hydrogen vehicle users. Additionally, a hydrogen refueling station will be built in the port area during long-term planning. A hydrogen refueling station will be built in the Li'ao area, which is located on the main roads and is in a location that is convenient for hydrogen vehicle users. Additionally, a hydrogen refueling station will be built in the port area during long-term planning. *Energies* **2022**, *15*, x FOR PEER REVIEW 19 of 28

> 3. Port Microgrid 3. Port Microgrid

The concept of an onshore power supply is regarded as an effective solution to make ports free of greenhouse gas emissions, air pollutants, vibrations, and noise pollution. The concept of an onshore power supply is regarded as an effective solution to make ports free of greenhouse gas emissions, air pollutants, vibrations, and noise pollution.

The Meishan port is located in the southeast of the zero carbon emission demonstration area. The port has 10 berths. Shore power facilities will be built successively for each berth and will be able to output 50 Hz and 60 Hz alternating currents (AC) with a voltage class of 6.6 kV. The Meishan port is located in the southeast of the zero carbon emission demonstration area. The port has 10 berths. Shore power facilities will be built successively for each berth and will be able to output 50 Hz and 60 Hz alternating currents (AC) with a voltage class of 6.6 kV.

An AC/DC hybrid microgrid will be built in the port area for shore-to-ship power, which can improve the utilization of renewable energy distributed in the port area. The microgrid is shown in Figure 15. An AC/DC hybrid microgrid will be built in the port area for shore-to-ship power, which can improve the utilization of renewable energy distributed in the port area. The microgrid is shown in Figure 15.

In addition, hydrogen energy applications will be explored in transport ships and in

According to different types of energy and demands in near-zero carbon emission demonstration districts, multiple energy storage facilities are planned, which will consist of electrical energy storage (EES), thermal energy storage (TES), hydrogen storage, and compressed air energy storage (CAES) facilities. EES and TES can handle energy balances from the supply and demand sides in time series. Hydrogen storage and CAES facilities

EES can transform electrical energy from power grids into a storable form and can

In the MINCEDD, there is no suitable terrain to construct pumped hydro storage facilities. Therefore, battery energy storage is widely utilized in this plan. There are three

In order to maximize solar energy use and reduce the peak–valley difference, residential, commercial, and industrial users should be encouraged to install PV with smallscale battery energy storage for self-use with the 0.4 kV access voltage class. A battery storage device operating from 0.1 kWh to 0.2 kWh can be allocated for each kilowatt PV device. Users will be able to obtain a one-time subsidy for battery energy storage devices.

Users with a large peak*–*valley difference, such as those in offices and commercial buildings, should be encouraged to install medium-scale power storage facilities on the user side, and these users will receive one-time subsidy for the installation of these power

**Figure 15.** The hybrid micro-grid in the port. **Figure 15.** The hybrid micro-grid in the port.

logistics vehicles.

4.3.4. Storage Side

1. Electrical Energy Storage

are oriented to the actual needs of industrial production.

ensure that it can be converted back into electrical energy if needed.

major ways to apply battery energy storage, which are as follows:

o Medium-scale power storage facilities on the user side

o PV with small-scale battery energy storage

storage facilities and discounted electricity prices.

In addition, hydrogen energy applications will be explored in transport ships and in logistics vehicles.

#### 4.3.4. Storage Side

According to different types of energy and demands in near-zero carbon emission demonstration districts, multiple energy storage facilities are planned, which will consist of electrical energy storage (EES), thermal energy storage (TES), hydrogen storage, and compressed air energy storage (CAES) facilities. EES and TES can handle energy balances from the supply and demand sides in time series. Hydrogen storage and CAES facilities are oriented to the actual needs of industrial production.

#### 1. Electrical Energy Storage

EES can transform electrical energy from power grids into a storable form and can ensure that it can be converted back into electrical energy if needed.

In the MINCEDD, there is no suitable terrain to construct pumped hydro storage facilities. Therefore, battery energy storage is widely utilized in this plan. There are three major ways to apply battery energy storage, which are as follows:
