Research on Application and International Policy of Renewable Energy in Buildings

Abstract

It has been proposed in China that the country should reach a “carbon peak” by 2030 and be “carbon neutral” by 2060. In the context of energy conservation and emission reduction, the country’s energy structure needs to be transformed to improve the technology level and more widespread consumption of renewable energy. The global renewable energy utilization situation is first analyzed in this study from the perspective of renewable energy and the buildings using it, highlighting the importance of the application of renewable energy in buildings. Secondly, from the perspective of solar energy utilization technology, ground source heat pump technology, and systems for managing energy use in buildings, the progressiveness of renewable energy applications in buildings is analyzed. The application of these technologies in buildings is demonstrated from various angles. Thirdly, the development prospect of buildings using renewable energy is discussed from the perspective of the promotion of renewable energy-powered buildings and green construction. The development prospects of buildings using renewable energy are discussed from the economic benefits of green finance, the promotion and social support of renewable energy, and the environmental benefits of green buildings. Finally, based on studies in the United States, the United Kingdom, Russia, and China, the international energy policy and development direction, as well as the evaluation criteria of green buildings, are discussed, along with an assessment system for green buildings that is complementary to the strategic agreement.

1. Introduction

With the exploitation of non-renewable resources such as oil and coal, the world’s energy capacity is becoming increasingly stressed. According to research by Shakeel M [1,2], the energy input is divided into two parts, comprising fossil fuel and non-fossil fuel, and the energy structure has a great impact on gross domestic product (GDP). At the same time, the author also puts forward suggestions for optimizing the energy model, especially for reducing the proportion of non-renewable energy, which will have a profound impact on future energy-saving technology and its direction. The application of renewable energy technologies has become an international issue. The 14th five-year energy-planning seminar reported that China’s renewable energy application technology has gradually matured, and energy transformation is an international trend. Positive policies are needed to encourage increasing the proportion of renewable energy technologies, strengthening people’s awareness of renewable energy buildings in terms of economic factors and application prospects, and promoting the application of renewable energy in buildings.

In addition to focusing on national development, we should expand our horizons to understand international energy policy and analyze the numerous and excellent international examples of renewable energy buildings. In combination with China’s current national energy situation, we should learn from developed countries regarding implementing renewable energy buildings in the context of their development basis. This paper focuses on the application of renewable energy in buildings from three perspectives: the current situation of global renewable energy applications, the application technology and incentive policy of renewable energy-powered buildings, and the future application of renewable energy-powered buildings.

2. Global Renewable Energy

Renewable energy technologies that have been applied to buildings mainly include solar energy, ground source heat pumps, wind energy, and biomass energy. The use of solar energy and heat pumps has expanded rapidly with continued technological breakthroughs in recent years. The relevant incentive policies are introduced by the government, including establishing the relevant foundations and improving the science and technology incentive system. Local governments put forward different guidelines for their own plans according to different circumstances, for example, the proportion of green power supply used for the world-famous Winter Olympic venues built in Beijing is at 100%, and the construction of four major wind and photovoltaic sites is focused in Shandong Province [3]. Given China’s large population, relative to developed countries, reducing costs and enhancing environmental responsiveness should be a priority.

According to the data shown in Figure 1, it is estimated that by 2027, the cumulative PV’s installed capacity may exceed 2350 GW. At the same time, the growth rate of PV is expected to exceed that of hydropower in 2024, natural gas in 2026, and coal in 2027. Similarly, due to the rapid growth of wind power generation, wind power generation is ranked second and hydropower generation is ranked third [4].

According to the data shown in Figure 2, we can predict energy trends in the next three years: renewable energy will become the main energy source for global applications, accounting for more of the demand than non-renewable energy. The specific distribution shows that the overall power generation exceeds 12,400 TWh. Although the capacity expansion rate of hydropower is lower than that of wind power and photovoltaic power generation in the observation period, hydropower is still one of the main sources of renewable energy power generation. It is predicted that by 2027, the electricity generated by renewable energy will account for about 40% of global electricity [4].

During the observation period shown in Figure 3, it is expected that the new capacity of renewable energy will reach a new high in 2027, an increase of 60% compared with that in 2026. At the end of the observation period, solar PV and wind energy will account for the majority of the new capacity of all renewable energy, at close to 95%. The technical reform of hydropower, bioenergy, geothermal, and photothermal power generation is difficult, and policy support will be limited. Solar photovoltaic power generation will set a record growth rate in 2027, accounting for 60% of all renewable energy growth [4].

In Europe, the average auction price (in US dollars) of photovoltaic solar energy in 2022 is 44% higher than that in 2021, and the average auction price of land-based wind energy is 21% higher than that in 2021, which is shown in Figure 4. In the Asia-Pacific region, the average contract price (in US dollars) of government-led auctions of solar and wind technologies has increased. In India, due to the depreciation of the Indian rupee against the US dollar, the average auction price in US dollars decreased by 1% but increased by 4% when calculated in Indian rupees. In Latin America, due to the high investment costs of PV and wind power, the benchmark price in Brazil and Chile is higher, which makes the contract price in the region higher [4].

Figure 5 shows the variations in the global total renewable energy installations from 2011 to 2020. It can be seen that the capacity of global total renewable energy installations shows a very obvious upward trend, and the growth rate has not slowed down. The prospects for renewable energy applications are promising, which is the result of a strong push toward renewable energy in various countries and indicates the arrival of a new wave of renewable energy development.

Figure 6 shows the variations in the total installed capacity of renewable energy facilities in all continents from 2012 to 2020. It can be seen that Asia is the leading country, and the rising trend is still sufficient considering the area factor. The second market leader is Europe, where the upward trend is not as obvious as in Asia because of its earlier renewable energy development here and in the more developed countries.

Figure 7, Figure 8 and Figure 9 show the installed increment capacity of renewable energy in various countries in Asia, Europe, the Americas, and Oceania in 2020. According to the increment analysis of each country, China, Russia, and the United States rank first in Asia, Europe, and the Americas, respectively. China’s installed increment capacity, with an increment of 894.88 GW, ranks first in the world, while the United States ranks second, followed by Brazil. The increase in the installed capacity of renewable energy is inseparable from the support offered by national policies, and the strong support of policies and technological improvement is related to the development of renewable energy. At the ninth meeting of the Central Financial and Economic Commission, held in March 2021, it was proposed that China should strive to achieve a carbon peak by 2030 and carbon neutrality by 2060, which is the direction and goal of future energy development.

It can be seen from Figure 10 that during the period from 2021 to 2026, China plans to increase the installed capacity of the renewable energy of solar photovoltaic and wind power by about 800 GW. Driven by the newly proposed renewable energy targets, China’s forecast growth has increased by nearly 70% over that of last year. These goals are aimed at accelerating the growth of renewable energy to achieve the government’s goal of zero net growth in 2060. In addition, China has set a target of reaching 40% of non-fossil power consumption between now and 2023, an increase of 5% compared with the previous target. At the same time, the Prime Minister also announced that China’s goal for photovoltaic power generation and wind power generation will be to reach 1200 GW, double the previous goal. In the past “12th Five-Year Plan” and “13th Five-Year Plan”, China has fulfilled the plan’s terms and, indeed, exceeded the target. With wind and solar photovoltaic power generation reaching more than 1220 GW in 2026, our main scenario forecast predicts that China will reach its announced target by 2030 and more than fulfill the plan.

3. Renewable Energy Applications in Building

In applying renewable energy, it is also important to integrate renewable energy with building projects in relation to the production of photovoltaic energy and other renewable energy production projects. Incentive policies and applications in renewable energy-based buildings should be more flexible and strengthened. According to the “Notice of the Ministry of Housing and Urban–Rural Development on Improving the Policy on the Application of Renewable Energy in Buildings and Adjusting the Management Mode of Fund Allocation issued by the Ministry of Finance in 2012” [7] and the “Notice of the National Energy Administration on Making Good Use of Renewable Energy Heating according to Local Conditions” [8], issued by the National Energy Administration in 2021, China vigorously promotes centralized and continuous promotion, encourages overall scientific planning, adopts heating technology according to the local conditions, and points out specific measures, including selecting key areas with suitable conditions as the centralized and continuous promotion demonstration areas, signing provincial and ministerial agreements to jointly promote centralized and continuous development. It is evident that the use of renewable energy-based buildings is a major aspect of the use of renewable energy.

During the “13th Five-Year Plan” period, significant progress was made in green buildings; building energy consumption has continued to decrease, and the energy efficiency of new buildings in cold areas can save 75% of energy, successfully completing the construction tasks during the “13th Five-Year Plan” period. In order to further promote the development of green buildings during the “14th Five-Year Plan” period, the Communist Party’s Central Committee has issued the “14th Five-Year” Plan for Building Energy Efficiency and Green Building Development, which proposed new planning and new goals. By 2025, China should further improve building energy efficiency, optimize the building energy structure, and lay a foundation for reaching a carbon peak by 2030.

3.1. Building Application of Solar Energy Technology

Since the “13th Five-Year Plan”, the distributed photovoltaic capacity of Shandong Province has increased from 440,000 kilowatts to 23.84 million kilowatts, ranking it first in China. Shandong Province is currently playing a leading role in China’s photovoltaic market. In response to the national call for energy transformation in the “14th Five-Year Plan”, Shandong Province issued the “14th Five-Year Plan” for the development of renewable energy in Shandong Province [9], which formulates renewable energy production targets, whereby consumption promotes development, and development affects the installation, thereby encouraging energy production and forming a favorable cycle through interaction. Shandong Province has built four large renewable energy sources in various areas. Driven by the “14th Five-Year Plan”, different localities have introduced policies encouraging the role of guiding public funds through the integrated allocation of bases, talents, and funds: improve the evaluation system, combine the market and policy to promote the relevant technical manual catalog, implement standardization, and establish the Shandong Energy Green Development Forum to strengthen international exchanges and learn advanced technologies.

Sun Valley in Shandong Province is an important solar energy research and development base in China. The temple of the Sun and Moon is in the valley. “The Micro-Discharge” building is currently the world’s largest solar energy building; it also integrates several ways of using solar energy, including energy storage technology regarding the water-stagnation layer in spring and autumn and cross-seasonal storage technology regarding the water-stagnation layer in the winter to extract heat energy for heating [10]. The improved radiant ceiling air-conditioning system replaces traditional air conditioning, which has the advantages of a small footprint, no feeling of wind, good heat exchange capacity of the radiant ceiling device, and the meeting of building load requirements by a small temperature difference between the supply and the returning water. The most astonishing result is the photovoltaic power production system of the “micro-row” building.

There are three kinds of photovoltaic modules used in the building: a starry photovoltaic module, a double-sided glass hollow building-integrated photovoltaics (BIPV) photovoltaic module, and a double-sided glass BIPV photovoltaic module, which have the effect of night beautification, lighting, and shading, respectively, while supplying energy. The overall energy efficiency of the building is as high as 88% through the application of various energy-saving technologies.

The role of luminescent solar concentrators (LSCs) is to concentrate the direct light and diffuse reflection, caused by light, and selectively provide transparency. The technology has great development potential. It can convert solar energy into heat energy for buildings and reduce the energy consumption of the whole building. [11]. Integrated photovoltaics have been used in buildings more and more widely in recent years; they can change the color that people see by reflecting the principal components of different colors of light. Figure 11 shows photograph of solar cell modules of different colors. The research shows that the first color parameter that causes relative efficiency loss by this method is brightness and the second is hue. [12]. Guiqiang Li presents a concise review of the integrated building concentrating devices and makes relevant classifications according to their actual functions, including building-integrated concentrated photovoltaic systems (BICPV), building-integrated concentrating solar thermal (BICST) systems, and building-integrated concentrating solar daylighting (BICSD), along with the combination of functions, i.e., BICPV/T, BICPV/D, BICST/D, and BICPV/T/D [13].

Solar-reflective “cool” walls can produce different results in summer and winter, reducing heat in summer and increasing it in winter [14,15]. Levinson found that the cost of household heating and ventilation energy can be saved by 31% through the flexible use of shading, reflection, and other methods [16]. The installation of a solar collector within the building envelope can convert the energy provided by the solar collector into the energy needed for the building. Antonio Gagliano evaluated the energy performances when building solar thermal facades (BSTFs) under different climate conditions, using TRNSYS software, and the results for the BSTFs bring great economic and energy-saving benefits because of the short time it takes to recover energy and carbon dioxide, reducing carbon emissions [17].

Daniel Valencia Caballero has studied a new photovoltaic skylight system shown in Figure 12. This system uses a static Fresnel lens. Its function is to make sure that buildings can receive the appropriate sunlight in the various seasons, and the system has been installed at Tecnalia shown in Figure 13. The results show that after using this system, compared to the other system, the production of photovoltaic power increases from 10% to 20% in spring and summer [18].

The latent heat storage of the phase change material (PCM) is beneficial for thermal energy storage (TES) in solar energy systems. The circulation of water between the glazing dissipates and stores solar-based energy in the water flow window (WFW). The results show that the power consumption ratio of the cooling systems can fall below 85%, using WFW [19]. Sara Brito-Coimbra mainly studied how Portugal uses passive solar technology in its Mediterranean climate. Four retrofitted passive solar technologies were reviewed, including glazing, sun shading, sunspaces, and Trombe wall technologies. An evaluation method is proposed and can be used to evaluate the feasibility of converting buildings using passive solar technology, which is shown in

Table 1. Performance indicators that can be used to assess the feasibility of retrofit projects with passive solar technologies [20].

Scope	Indicator	Unit
Solar availability	Solar irradiation on the façade surface	kWh/m2/year
	Hours of solar exposure	Hours
Thermal performance and comfort	Discomfort period	Hours; %
	Heat gain	MJ/m2; kW/m2
	Heat transmission(Heat flux)	W/m2
	Predicted Mean Vote (PMV)	-
	Relative humidity	%
	Temperature(surface:glazing and massive wall;cavity)	°C
	Time lag	Hours
Indoor air quality and acoustics	CO2 concentration	ppm
	Acoustics	-dB; RT60
Energy efficiency	Cooling energy needs(or cooling energy needs savings)	kWh; kWh/year; %
	Energy storage(and release)	Hours
	Heating energy needs(or heating energy needs savings)	kWh; kWh/year; %
Environment	CO2 emissions(production and operational phase)	kg CO2 eq
	Energy demand(production and operational phase)	kWh; kWh/m2
Economic	Annual savings	€; %
	Internal rate of return (IRR)	-
	Investment costs	€
	Net present value(NPV)	-
	Payback period(PP)	Years
	Savings-to-investment ratio(SIR)	-

[20].

3.2. Building Applications for Geothermal Pump Technology

A renewable energy supply system was adopted in Liangxi Town, Enping City, in Guangdong Province. According to the regional characteristics of beautiful scenery and a pleasant environment, the use of traditional air conditioning technology will face some problems, such as the installation of units and cooling towers occupying a great deal of space, the local temperature being too high to cause shutdown protection, resulting in reduced energy efficiency. Overall, the use of a ground-gas-based geothermal pump system is a better choice. Due to the presence of nearby waterways, the outdoor system may use surface water for heat exchange, and the coils are a closed system, which will not cause water pollution. The application of geothermal heat exchangers, according to the operating cost analysis, yields a cooling and heating saving rate of about 60%.

A geothermal pump, in combination with the building’s energy supply, can significantly improve the economic benefits. Depending on the characteristics of the geothermal pump, it can achieve warming in winter and cooling in summer, reduce harmful emissions, and respond to national policies to contribute to energy conservation and the protection of the environment. The combined technology of geothermal pumps and solar energy is an important means of using renewable energy. This concept was first put forward in the West. Penrod [21,22] proposed that the combination of solar energy and geothermal energy could realize both advantages and disadvantages in complementing each other, which could reduce the number of underground wells while maintaining the balance of geothermal energy and good environmental and economic benefits. At the same time, Penrod also offered a prototype system that laid a solid foundation for future research. Biglarian [23] proposed applying the combination of a geothermal pump and solar energy in an independent single building in the context of the cold climate in northwestern Iran; from the perspective of economic benefits, compared with the three heating methods of the geothermal pump, air source heat pump, and gas heating alone, the running time is 20 years, and the study showed that the combined system of geothermal pumps and solar energy offers more advantages. The advantages of the compound system can be used as a reference for the cold regions of the north, and the energy system can be improved accordingly. Guo Anzhu [24] conducted a numerical simulation on a solar geothermal pump composite system with two water tanks, used for building heating, and found that the composite system had the best economic benefits and the lowest annual energy consumption.

Archan Shah et al. reported that the emission of a ground-source heat pump used in buildings is generally lower than that of other traditional HVAC systems. Considering the high installation cost caused by deep-hole drilling, a shallow-hole ground-source heat pump is a better choice [25]. Jeong Soo Shin et al. proposed a comprehensive ground-source heat pump system, which is composed of two ground-source heat pumps for air conditioning and domestic hot water that share a groundwater loop. Research shows that the efficiency of the split loop system exceeds that of each heat pump alone, which is shown in

Table 2. Estimated annual electricity savings of GSHPch and GSHPhw, by individual operation and integrated operation [26].

Heat Pump Operations		Cooling Season (From May to October)	Heating Season (From November to April)
Individual operation of GSHPch and GSHPhw on its own ground loop	For heating or cooling (kWh)	69,693 (100%)	121,677 (100%)
	For service hot water (kWh)	22,708 (100%)	34,901 (100%)
	Sum (kWh)	92,401 (100%)	156,578 (100%)
Individual operation of GSHPch and GSHPhw on the shared ground loop	For heating or cooling (kWh)	55,274 (79.3%)	108,205 (88.9%)
	For service hot water (kWh)	19,498 (85.9%)	33,320 (95.5%)
	Sum (kWh)	74,772 (80.9%)	141,525 (90.3%)

[26].

Davide Menegazo discussed the state of development of geothermal heat pump technology in Europe, from the point of view of piping materials, backfilling materials, working fluids, etc. [27]. Diana D’Agostino found that the ground-source heat pump system can significantly reduce carbon emissions in the evaluation of ground-source heat pumps [28]. Figure 14 and Figure 15 show CO₂ emissions reductions for the different solutions in Palermo and Milan.

The ground-coupled heat pump is a system with great advantages for heating and cooling buildings. In particular, one study compares the hybrid heat pump, using ground and external air as radiators with common solutions. The result is that compared with ordinary heat pumps, hybrid heat pumps show better performance and limit the thermal drift of the ground temperature [29]. Figure 16 shows the scheme of the new hybrid heat pump.

Yaran Wang et al. [30] found that a coaxial deep-hole ground-source heat pump can obtain more heat than other types of ground-source heat pumps. At the same time, it is not necessary to be concerned about environmental pollution due to the closed water cycle. This is a very effective method for using a geothermal heat pump system with a deep well coaxial heat exchanger, one that is widely known today. However, to decrease the total energy consumption of the system, the water flow in the coaxial deep well heat exchanger is less optimized when meeting load variations in the heating season. The total power consumption of the system is reduced by optimizing its performance. Figure 17 shows the way that heat extraction power varies with different flow rates. Figure 18 shows the relationship between total energy consumption and throughput over two periods, along with the optimization process.

Ratchawang, S [31] analyzed the application of a ground source heat pump in a refrigeration system in Southeast Asia. There is greater demand for refrigeration because of the tropical climate of Southeast Asia. At the same time, it is necessary to study the temperature and flow rate of the groundwater, which significantly affect the effectiveness of the geothermal heat pump. Nicola Massarotti et al. [32] established that the heat pump system can be applied to historical buildings when in heating and cooling modes through the application scenario of coupling heat pumps in historical buildings in southern Italy. This research proves that the geothermal heat pump system can be used for energy conversion and shows the possibility of their application in buildings with cultural protection value. At the same time, this technology complies with the current laws and regulations, as opposed to the use of fossil fuels; this technology can reduce carbon emissions by 53%.

3.3. Building Energy System

Sutton Town, located in Beddington in the London borough of Sutton, is the first community with zero carbon dioxide emissions in the UK and the world and was completed in 2002. A “zero-carbon community” is not completely free of carbon emissions, but rather, is free from the use of environmentally unfriendly traditional fossil energy sources, such as coal and oil, through other means, for example, the smart use of recyclable building materials, the installation of solar energy and rainwater utilization devices, etc. Many details in the community are designed to be environmentally friendly and energy-efficient, avoiding additional environmental burdens from the construction and use of the community as much as possible. The building materials of the residential buildings are all specially made recyclable materials with thermal insulation properties. Solar cells are laid out on the south side of the roofs, and various plants are planted on the north side. The handrail of the stairs in the building is made of waste steel pipes. Each household is equipped with a water heater with a height of more than one meter. In addition to providing domestic water, the water heater can also automatically release heat when the room temperature is low, to assist in heating. Community transportation also encourages “green travel”, and charging piles are installed in the community to facilitate residents in charging electric vehicles.

The vigorous development of the Beddington community has proved that a “zero carbon community” is feasible. We can learn from this project to achieve comprehensive zero carbon as soon as possible and encourage the promotion of zero-carbon application technology in China. Solar energy technology will be one of the most important energy supply methods in the future. There are advantages to using solar energy technology in rural areas. Compared with coal-fired heating, solar energy heating can reduce energy consumption in winter and reduce the emission of polluting gases.

Chao-Tsun Ma et al. [33] studied the application of a hybrid energy storage system for green energy; they found that the reliability of renewable energy needs to be improved although it possesses the advantages of inexhaustible supply and being environmentally friendly. The combination of renewable energy production systems and energy storage systems can increase reliability and promote the development of the global energy system in moving toward distributed renewable energy. Elena Korol et al. [34] analyzed and evaluated the green wall system in energy-saving residential buildings by using the model life-cycle assessment model, which includes the installation process, post-maintenance, etc. A system was designed to assess the applicability of energy-efficient green building technology ahead of time [35]. The system assessed energy-efficient technologies used in a building, from multiple perspectives at the initial design stage, and quantify them to give people a direct insight. The goal of the system is to intuitively test the best green energy-saving technology for the projected building at the initial design stage. Figure 19 shows the framework of the pre-evaluation system.

Kuo-Hsiung Tseng et al. [36] built a campus green energy-monitoring system in a building that can collect the measurement data of the green environment and transmit it to the cloud for analysis through the Internet of Things. Green roof technology serves the various functions of beauty, relieving the city’s heat island effect, and storing rainwater. Gulsah Hancerligullari Koksalmis et al. discussed the possibility of promoting green roof technology in Turkey [37].

4. Development of Renewable Power Buildings

Market promotion and the purchase and use of renewable energy buildings are very important for the future development of renewable energy buildings. Good market prospects and the assessment of utilization have a good promotional effect on renewable energy buildings. To some extent, on the basis of the relevant energy policies and incentives of the government, the market direction and consumption demand can also reflect the future development of renewable energy buildings. Green financing is a way of promoting carbon neutrality in the marketplace. In 2016, the Central Bank of China, together with other ministries, released its Guidelines for Building a Green Financial System. In October 2021, the Opinions of the CPC Central Committee and the “State Council on Completely, Accurately, and Completely Implementing the New Development Concept and Doing a Good Job of Carbon Peak and Carbon Neutralization” mentioned that China should actively develop green finance, improve the relevant standard system, and promote its implementation. In the past, people have always thought that renewable energy buildings offer only social advantages, but not economic advantages. However, with the continued improvement and promotion of green finance, there will be a growing recognition of the role of green finance and markets in promoting renewable energy. The two will be closely related and will have a wider perspective of market development, so as to truly achieve the sustainable development of renewable energy buildings.

4.1. Promotion of Renewable Energy Buildings

Currently, renewable energy residential buildings account for a certain proportion of ordinary residential buildings, and solar heating is the basic method for using renewable energy in residential buildings. People pay more attention to geographic location, home type, and price when choosing a home, and rarely see renewable energy buildings as advantageous. The house-users’ cognition of the house environment is more about the advantages and disadvantages of the outdoor green environment and the convenience of the surrounding living environment, while cognition of the quality of the indoor living environment and the energy-saving effect brought about by the application of renewable energy is relatively small.

While strengthening the implementation of renewable energy policies, the government should build and promote renewable-energy housing. At the same time, in combination with the current trends of urban and rural reconstruction and the renovation of dilapidated buildings in old residential areas, renewable energy buildings will be more visible to people, highlighting their economy and livability [38,39]. This will increase the popularization of renewable energy applications and the impact of energy savings on the general public and allow people to better understand and understand the benefits of renewable energy buildings, so they can better capitalize on people’s livelihoods [40].

Allowing people to better understand the benefits of renewable energy buildings means that they can better capitalize on people’s livelihoods. To do this, we must advocate the efforts of all sectors to promote renewable energy buildings, encourage more enterprises to participate in it, increase the publicity of policies related to renewable energy buildings, introduce incentives from tax policies, financial subsidies, and other aspects, and strengthen incentives for renewable energy buildings or green buildings. The government should strengthen the interpretation of renewable energy policies and corresponding incentive policies, so that the public can understand the advantages of renewable energy technology application and social development, thereby improving public acceptance.

4.2. Green Construction Development

With regard to renewable energy buildings, the quality assessment of renewable energy buildings should be improved in terms of building materials, the construction process, the design of building energy systems, etc. Green construction technology is also necessary. During construction, the construction company should assume social responsibility [41], paying attention to the coordination of environmental protection materials and the environmental protection sensitization of construction staff. In the process of house renovation or decoration, green construction technology should be preferred from the perspective of energy conservation, environmental protection, and health; more construction waste should be avoided in order to improve the aesthetics of the actual construction process.

One of the key tasks of the “14th Five-Year Plan” is to promote the promotion and application of green building materials. In government-invested projects, green building materials should be used as a model, while the research and development of related technologies should be strengthened to promote green products and support application technologies. In this regard, the Country Garden Group, one of the largest new urbanized residential builders in China, has actively developed the green building industry, as seen in Forest City, Shunde Country Garden, Guangzhou Phoenix City, etc., and has truly realized adaptation to local conditions with well-designed projects. From the perspective of China’s national conditions and the relevant policy formulation, the future development of green construction and construction technology has a bright future; it is widely used in the field of construction engineering [42], and the green building index is included in the residential sales contract.

We need to use these proven technologies and successful examples to make people realize that green buildings are good for the environment and human health, and offer environmental benefits compared to other buildings. For example, reasonable green space planning around green buildings makes people happy; environmentally friendly building materials keep people away from air pollution.

5. Renewable Energy Application Policy Analysis

5.1. International Policy Analysis

The renewable energy department in the United States has attracted more than USD 500 billion in investment since 2004, which is the largest source of private sector infrastructure investment in the United States [43]. The U.S. PV investment tax credit, enacted in 2006, has been one of the most successful federal policies in promoting PV development. A tax credit is essentially a credit for income taxes that an individual or business would otherwise pay to the U.S. federal government. Since the policy was introduced, the U.S. PV industry has grown by more than 10,000%. Voluntary procurement, corporate off-take, and government mandates have driven the growth of PV in the U.S. during the past several years.

According to the United States Energy Administration (EIA)’s energy-related carbon emission figures—the 2020 Carbon Dioxide Emissions [44]—energy-related carbon dioxide emissions in 2020 fell to their lowest level since 1983. Although the United States needs a large amount of energy, different types of energy are concentrated in different regions and are unevenly distributed.

Natural gas and coal remain the largest sources of electricity generation in the United States in 2020, accounting for about 59%. As a major developed country, the United States requires a great deal of energy to ensure its proper functioning and development. Therefore, how to solve this energy tension has become a hot issue; the United States government also attaches great importance to exploring the application of renewable energy. In order to solve the environmental problems caused by the consumption of traditional fossil energy and to promote the development of renewable energy sources, the United States has issued a series of incentive policies issued by the federal and state governments, and the green power market has emerged, as the times require.

There are two main types of green electricity markets in the United States. The first is the compliance markets, based on the renewable energy quota system; the second is the voluntary markets [45]. The compliance markets are established by the state government, under the Renewable Portfolio Standards (RPS), to help responsible parties with quota obligations to meet their renewable energy quota targets. Voluntary markets are the energy markets where consumers purchase renewable energy because of their own desire to move to green power. In addition, there are corresponding support mechanisms, including a tracking system based on the Green Electricity Exchange Contract and a tracking system based on the green certificate number. In general, the RPS sets the minimum requirements for providing a portion of electricity from a given renewable energy resource by a specified date. Maine, which implemented a renewable energy quota system that required utility companies to sell a certain proportion of their power from renewable energy, increased its overall RPS goal in June 2019 to require 100% of electricity sales from renewable sources by 2050, which was up from the previous goal of 10% of electricity being generated from renewable sources in 2017 [46]. The District of Columbia increased its RPS target in January 2019 to require 100% of renewable electricity sales by 2040.

The European Commission published the European Green Deal on 1 February 2019. The main purpose of the agreement is that Europe will work with other countries in the world to take action regarding the sustainable development of the world’s green economy; the agreement covers many fields, including transportation, energy, construction, agriculture, and other areas. In order to achieve the effective use of energy and the sustainable development of society, Europe will continue to invest funds and provide economic support. Behind the “European Green Deal”, we can see the determination of Europe to transition to green energy.

The UK government has attached great importance to the development of green buildings and has introduced the concept of the Green Deal, which is similar to a housing label from which local people can directly benefit. People can apply for exclusive loans to renovate their old homes, giving preference to companies with green deal credentials, so that they can help design the best energy-saving solutions, specifically waterproofing, double glazing, renewable energy generation, solar heat pumps, etc. In October 2019, the British Housing Minister, Robert Jenrick MP, announced the UK government’s “new green standards for new homes [that] will bring about an environmental revolution in residential construction” [47], laying out future healthy building standards, which will ban polluting fossil-fuel heating systems, such as coal-fired boilers, in new homes by 2025, replacing them with the latest generation of clean technologies, such as air-source heat pumps and state-of-the-art solar panels. The implementation of this policy will significantly reduce the carbon emissions from residential homes. According to the World Energy Statistical Review 2021, published by British Petroleum [48], the UK’s primary energy consumption declined by 11% in 2020, the largest decline since 1980; the share of renewable energy power generation exceeded 40% for the first time, and the proportion of primary energy structure in the UK increased to 17%; oil consumption fell to 1.2 million barrels per day, a decline of 22% due to the impact of the sharp decline in aviation activity caused by COVID-19.

The Russian government has also focused on green energy. In September 2021, the Russian Association of Market Committees developed a co-ordination system [49], the main goal of which was to ensure the circulation of various green instruments (bilateral treaties, certificates, and other instruments) in Russia that can be used to identify the electricity consumption of renewable energy and low-carbon generation facilities. For green energy support, the Russian government has also pursued a series of recent initiatives, holding an all-Russian energy efficiency and conservation competition in December 2021 [50]. The event was organized by the Ministry of Construction and Housing Utilities of Russia, the Ministry of Energy of Russia, the State Fund for the Promotion of Housing and Housing Reform, and the National Agency for Energy Efficiency, independent non-profit organizations, the main aims and objectives of which are to promote energy efficiency and conservation projects in the economic and budgetary sector at the federal, regional, and municipal levels, encourage the promotion of energy-efficient lifestyles among the population, promote energy-efficient overhauls of common property in apartment buildings, and strengthen the energy culture. The international forum, “Russia Energy Week 2022”, was held in Moscow from October 12 to October 14 under the auspices of the Russian government [51], at which event the Russian President, Vladimir Putin, proposed to take full advantage of natural gas resources to create a gas hub to connect other countries to each other.

China is actively developing renewable energy utilization technologies and promoting green power, taking into account the dual characteristics of the physical consumption of electricity and green certificate prices, along with the continuous improvement of the green power market. By the end of November 2021, China’s installed power generation capacity was about 2.32 billion kilowatts, which was up 9% year-on-year. Among them, a wind-power installed capacity of about 300 million kilowatts was up 29% year-on-year; the solar power’s installed capacity was about 290 million kilowatts, up 24.1% year-on-year. At the same time, the level of renewable energy use continues to increase. In 2021, the utilization rates of wind, photovoltaic, and hydro energy reached about 96.9%, 97.9%, and 97.8%, respectively [52]. In order to improve the energy mix and achieve a better future, it is important to increase the share of renewable energy applications. Dadi Zhou, vice-president of the China Energy Research Association, when speaking in a workshop on green low-carbon development strategies under the goal of carbon peaking and carbon neutrality, suggested that transformation of the energy system is crucial to achieving the goal of carbon peaking and carbon neutrality and that society, as a whole, should be carbon neutral by 2060; the energy system needs to achieve zero-carbon status earlier, with the power system achieving this by 2040–2045 [53].

5.2. Application of the Evaluation Criteria

There are 26 assessment systems or evaluation tools for green building that are used for evaluating green buildings around the world. The China system, GBES, the U.S. system, LEED, the U.K. system, BREEAM, the Canadian system, GB tools, and the Japanese system, CASBEE, are some of the major assessment systems.

The world’s most well-known evaluation standard for renewable energy buildings is LEED (Leadership in Energy and Environmental Design), a green building evaluation system created and implemented by the U.S. Green Building Council, intended to effectively reduce negative environmental and occupant impacts in design, standardize a comprehensive and precise concept of green construction, and prevent the blind greening of buildings. This standard has been made legally mandatory in some US states and certain countries [54]. LEED is also considered to be the most influential international standard for evaluating green buildings. LEED’s scoring criteria are divided into six areas: Sustainable Sites, Water Conservation, Energy and Atmosphere, Materials and Resources, Indoor Environmental Quality, and the Innovation and Design Process, each with its corresponding specifications and requirements. However, beyond the criteria, most importantly, the existence of LEED gives a market value to the building or company being evaluated. The results of LEED certification can be very useful for improving the reputation or value of a real-estate business. This rating represents a clear message that the livability and affordability of a building are beneficial, that it is worthwhile for consumers to buy green buildings, and that any investment made will be rewarded. Ordinary people can live more comfortably in such a building and consume less energy; businesses can be socially responsible, while their workers can be more productive and less costly to manage.

In order to determine the overall evaluation of new building construction projects and evaluate some elements in the BREEAM system, which comprise environmental section weightings, minimum BREEAM standards, and BREEAM rating level benchmarks [55].

Table 3. The BREEAM environmental section’s weightings [55].

Environmental Section	Weighting
Management	12%
Health and Wellbeing	15%
Energy	19%
Transport	8%
Water	6%
Materials	12.5%
Waste	7.5%
Land Use and Ecology	10%
Pollution	10%
Total	100%
Innovation(additional)	10%

and

Table 4. BREEAM rating benchmarks [55].

BREEAM Rating	%Score	Performance Percentage
Outstanding	≥85	Less than top 1% of U.K. new non-domestic buildings (innovator)
Excellent	≥70	Top 10% of U.K. new non-domestic buildings (best practice)
Very good	≥55	Top 25% of U.K. new non-domestic buildings (advanced good practice)
Good	≥45	Top 50% of U.K. new non-domestic buildings (intermediate good practice)
Pass	≥30	Top 75%Top 25% of U.K. new non-domestic buildings (standard good practice)
Unclassified	<30

show the BREEAM environmental section’s weightings and rating benchmarks.

The CASBEE assessment tools comprise different scales, including building scale, housing scale, city scale, and urban scale. Figure 20 shows a schematic diagram of the CASBEE tools [56].

The first edition of the Chinese Green Building Evaluation Standard (GBES) was published by the Ministry of Construction [57]. GBES, jointly edited by the Chinese Academy of Architecture and the Shanghai Academy of Building Sciences, has gone through three editions and two revisions since its issuance in 2006 until 2019. The concept of “people-oriented” assessment has always been respected during the process of developing the Green Buildings Evaluation Standard. In combination with the tide of a new era, the most recent revision of the GBES is aimed at realizing the needs of the Chinese people to achieve a better life. GBES (2006) is the first national standard for green building evaluation in China, which plays a pioneering role and provides a basic model for future revision and improvement. With progress in current times and the development of society, the cognition of green buildings has gradually improved in terms of GBES (2014). The old version of the standard was evaluated from an engineering perspective and cannot meet people’s needs for health, comfort, and environmental protection in green buildings. At the same time, the application scope of the new version extends to various civil buildings, from residential buildings to public buildings, including office buildings, commercial buildings, and hotel buildings. The measurement and estimation method changed from the element counting method to the fraction counting method.

The original seven indicators in GBES (2014) were changed to five indicators in GBES (2019), in order to improve the building quality and better reflect the people-oriented spirit of the new standard, paying more attention to the harmonious coexistence of humans, the environment, and nature. Green buildings are redefined in GBES (2019), aiming to save resources, protect the environment, and reduce pollution during the building’s whole life cycle. In it, the ideal building is a high-quality structure that provides people with a comfortable, reassuring, and relaxed life, and realizes the wonderful integration of humans and nature. GBES (2019) also optimizes the scoring standard and adds a new building grade. At present, the assessment standard for green buildings has been listed by the Ministry of Housing and Urban–Rural Development as one of the ten key standards to promote the high-quality development of cities, which is of great significance in practice when using the concept of green development in the construction field, and has initially formed a new pattern of “leading” the world’s green building standards.

GBES is divided into five aspects [58], including safety and durability, health and comfort, the occupants’ convenience, resource saving, and environmental livability. It takes into account the various architectural design and planning standards in China, which is an effective guide for the evaluation of renewable energy buildings or green buildings.

Table 5. Evaluation criteria.

	Basic Score of Control Item	Full Score of Evaluation Index Scoring Items					Full Score of Improvement and Innovation Bonus Items
		Safety and Durability	Health and Comfort	Occupant Convenience	Resources Saving	Environment Livability
Pre-evaluation score	400	100	100	70	200	100	100
Evaluation score	400	100	100	100	200	100	100

shows the specific evaluation criteria.

The total score for green buildings is based on the following formula:

Q = (Q_0 + Q_1 + Q_2 + Q_3 + Q_4 + Q_5 + Q_A)/10

where:

Q—Total score

Q_0—Basic score of the control items. We take 400 points when all control requirements are met.

Q_1–Q_5—The scores of the five categories of indicators in the evaluation index system.

Q_A—The score of improvement and innovation, plus items.

The green buildings are divided into four levels: the basic level, the one-star level, the two-star level, and the three-star level.

Basic level: the building meets the requirements of all control items.

One-star level: the building meets the requirements of all control items; the score of each index-scoring item is not less than 30% of its full score. The overall decoration of the building meets the national standards, it meets the relevant star-level technical requirements, and the total score reaches 60 points.

Two-star level: the building meets the requirements of all control items, the score of each index-scoring item is not less than 30% of its full score, the overall decoration of the building meets the national standards and meets the relevant star-level technical requirements, and the total score reaches 70 points.

Three-star level: the building meets the requirements of all control items, the score of each index-scoring item should not be less than 30% of its full score, the overall decoration of the building meets the national standards and meets the relevant star-level technical requirements, and the total score reaches 85 points. Figure 21 shows the green logo motif.

GBES is used to optimize the architectural design. University buildings play an important exemplary role in the future sustainable development of cities. Figure 22 shows the green BIM decision cycle model, which is applied in building design successfully, leading to an efficient optimization effect [59].

Whether it is the government’s policies, strategic agreements, or various evaluation standards, we can clearly realize the significance of these systems. It is obvious that the government’s policy is to encourage the development of the green building industry. The strategic agreements of various countries reflect the importance of win-win cooperation and reduce the energy crisis. The update of the green certification system makes the certification classification more scientific and gives the building a more appropriate value. This also reveals the interaction and logic between government policies, strategic agreements, and green certification. The implementation of renewable energy buildings is the trend of the current times, and their purpose is to make the world cleaner.

6. Conclusions

With the new wave of carbon peak and carbon neutrality, as proposed in the “14th five-year plan”, the relevant policies of renewable energy buildings will be perfected more and more, and people will gradually realize the importance of renewable energy buildings [60]. Advanced renewable energy technology and assessment systems are becoming more common in the world, forming the hull of the huge vessel of renewable energy construction. Driven by the correct market and policy directions, renewable energy buildings will have better development prospects. Our conclusions are as follows.

(1)

In terms of the current situation regarding renewable energy development in the world, the proportions of hydropower, photovoltaic, natural gas, and other renewable energy sources have changed, compared with the proportions of traditional non-renewable energy sources. According to the survey, the proportion of renewable energy sources has continued to increase. At the same time, by comparing the auction contract price and the installed capacity of renewable energy, it is clear that the promotion of renewable energy is gradually improving in China and other countries.

(2)

The application of renewable energy technology in buildings, from the perspective of solar energy utilization technology, ground-source heat pump technology, and other technologies, has been analyzed, and, at the same time, the latest technological developments have been discussed. The development prospects of renewable energy buildings are discussed from the point of view of the economic benefits of green finance, the promotion and social support of renewable energy, and the environmental benefits of green buildings.

(3)

The energy agreement and green building certification system have been analyzed in this paper. The green certification system is constantly being updated to make the certification classification more scientific, and the strategic agreements of various countries provide good prospects for worldwide energy development.