Adaptation of buildings for climate change: A literature review

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FACULTY OF ENGINEERING AND SUSTAINABLE DEVELOPMENT

Department of Building Engineering, Energy Systems and Sustainability Science

Adaptation of buildings for climate change

A literature review

Cheng Cheng June 2021

Student thesis, Advanced level (Master degree, one year), 15 HE Energy Systems

Master Programme in Energy Systems Supervisor: Björn Karlsson Examiner: Magnus Mattsson

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Abstract

In September 2020, Northeast China suffered three unprecedented typhoons in half a month, and there was a freezing rain in early November, all of which led to the large- scale urban power failure. The occurrence of these phenomena makes people directly see climate change and its impact on the living environment of human beings. Many studies have shown that the cause of climate change is the increase of artificial greenhouse gas emissions since industrialization. In addition to the increase of extreme weather disasters, the most direct manifestations of climate change are the rising temperature, droughts, and rising sea levels. The building sector accounts for 39% of global greenhouse gas emissions and 36% of energy consumption. To ensure the long-term integrity and normal operation of buildings, we need to understand the impact of climate on buildings, and how to deal with it. This paper reviews the literature on climate change and building energy by searching search engines and literature databases. For extreme weather, most literature talks about the impact of power failure, the main strategy is to improve reliability, resilience, sustainability, and robustness, it can help reduce losses and recover as soon as possible. On the other hand, the methods of adaptation to and mitigation of non-disaster weather are reviewed from the perspective of sustainability. This paper mainly reviews the methods of passive technology and strategy for exemplary buildings, building envelope, passive ventilation, lighting/shading, solar energy, bioenergy, dehumidification, passive cooling, and design strategy. According to the local climate, the geographical characteristics of the building, to develop comprehensive passive technology and strategy, can meet or close to meet their energy saving, emission reduction, comfort needs. This paper can provide a technical and strategic reference for the building sector to deal with climate change.

Keywords: Climate change, Extreme weather, Building energy efficiency, Passive houses

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Preface

First I want to thanks my supervisor Björn Karlsson, who approved my thesis.

Thanks, Nawzad Mardan who give me patient help throughout the whole thesis project.

Thanks to my examiner Magnus Mattsson allow me to present my thesis.

Thanks, Noor Jalo who helped me with the communication and Zoom software testing.

Thanks, Jonathan Rahmqvist to help me with the course registration.

Thanks to the people in the University who helped me directly or indirectly.

Thanks to the University of Gävle for giving me the opportunity to study in the master's program in Energy System.

I would like to thanks Mr.Wang and Mr.Guo the project team leader who gives me a long holiday to-do the full-time thesis work.

Thanks to my friend Mr.Zhao, Ms.Ma, Ms.Zhang Xintong, and Ms.Lei give me patient help.

Finally, I want to express my gratitude to my sister Xin Hao, brother Sun Wei, my mother, my girlfriend Zhang Ning, and other families, without your support I cannot finish the study.

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“When we excavate the remains of past civilizations, we very rarely find any evidence that they as a whole society made any attempts to change in the face of a drying climate, a warming atmosphere, or other changes… I view this inflexibility as the real reason for collapse.”

--Harvard archaeologist Dr.Jason Ur

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Nomenclature

Abbreviation and Acronyms

Letters Description

BIPV Building-integrated photovoltaics

BIPSET Building-integrated passive solar technology CBR Case-based reasoning

CFL Compact fluorescent lamp

CNKI China national knowledge infrastructure COP Coefficient of performance

DG Distributed generation DNN Deep neural network

DOI Digital object identifier system DPP The payback period

DRL Deep reinforcement learning EAHE Earth-air heat exchanger

EIA The US energy information agency Heed Definition of Heed by Merriam-Webster HVAC Heating, Ventilation, and Air Conditioning IEA International energy agency

IPCC Intergovernmental Panel on Climate Change IRR Internal rate of return

LCA Life cycle assessment LCC Life cycle cost LED Light emitting diode LLD Lighting load density MDP Markov decision process

NASA National Aeronautics and Space Administration NPV Net present value

NZE Net-zero energy

NZEB Near-zero energy building PCM Phase change material PEB Positive energy building PEC Personalized evaporative cooler PEC Personalized evaporative cooler PV Solar photovoltaic

PVT Photovoltaic-thermal RL Reinforcement learning SST Setpoint temperature SWHs Solar water heaters

TRNSYS Transient system simulation tool

UNT Underground tank

XAI eXplainable artificial intelligence

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v ZEB Zero energy building

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1 Introduction ... 1

1.1 Background ... ... 1

1.2 Aim ... ... 2

2 Methods ... 3

3 Result ... 6

3.1 The Impact of climate change on buildings ... ... 6

3.2 Adaptation of building for climate change ... ... 9

3.2.1 Methods for dealing with disaster-type extreme weather ... 9

3.2.2 Adaptation and Mitigation ... 11

3.2.2.1 Exemplary building ... 11

3.2.2.2 Building envelope ... 13

3.2.2.3 Passive ventilation ... 16

3.2.2.4 Lighting and shading ... 18

3.2.2.5 Solar energy ... 21

3.2.2.6 Bioenergy ... 26

3.2.2.7 Dehumidification ... 28

3.2.2.8 Passive cooling ... 29

3.2.2.9 Design strategy ... 31

4 Discussion ... 32

5 Conclusion ... 33

5.1 Study results ... ... 33

5.2 Outlook ... ... 33

5.3 Perspectives ... ... 34

References ... 35

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1 Introduction

1.1 Background

In September 2020, Northeast China was hit by three unprecedented typhoons in half a month and a freezing rain in early November, which led to a large-scale power failure in cities. The occurrence of these phenomena makes people directly see the impact of climate change and the living environment of human beings. According to the IPCC report, the biggest contribution to warming comes from the increase of CO2 concentration in the atmosphere since 1750 [1]. Even if the emission is stopped immediately, the temperature will continue to rise for centuries because the greenhouse gases emitted by human beings in the past have already existed in the atmosphere. Limiting temperature rise will require substan- tial and sustained reductions in greenhouse gas emissions. Climate change is a complex prob- lem, which needs complex response measures. The most common strategy is to reduce the impact of climate change (Mitigation) and to deal with the impact of climate change (Adap- tation). In short, the purpose of mitigation is to avoid the unmanageable, and the purpose of adaptation is to manage the inevitable [2].

In 2010, buildings accounted for 32% of the world's final energy use, 19% of energy-related greenhouse gas emissions (including electricity-related), about 1/3 of black carbon emissions, and 1/8 to 1/3 of fluorine emissions. This quota is expected to increase due to climate change, urbanization, and higher standards of living comfort. By the middle of this century, energy use and related emissions may double or even triple[3]. However, the building sector is also considered to be the easiest to achieve results through transformation [3-5]. A large number of existing buildings and new buildings are facing the demand for energy conservation and emission reduction. Passive buildings, low energy consumption buildings, zero energy consumption buildings, green buildings have become the main trend.

This literature review focuses on the passive technologies and strategies adopted by the building sector to adapt to and mitigate climate change from the perspective of the energy system.

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2 1.2 Aim

This paper reviews the relationship between climate change and buildings, including climate change reports and peer-reviewed scientific articles on building energy.

The first aim is to collect knowledge about the impact of climate change on buildings.

The second purpose is to gather technologies and strategies for buildings to cope with climate change from the perspective of sustainable development.

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2 Methods

To understand the background and development of this study, the author consulted a great deal of literature, covering scientific papers, books, reports, news media websites, science websites, business websites, etc., examples of which are Science Direct, NASA, IPCC, IEA, Wikipedia and business websites such as Project Drawdown（www.drawdown.org）. In addition, the keyword “climate change” has been searched on YouTube and other media websites.

According to the objectives, this study is divided into two parts, namely, Part 1 Impact of Climate Change on Buildings and Part 2 Adaptation of Building for Climate Change. The conceptual framework of this study is depicted in Fig.1.

Fig. 1 Study concept framework

 Part 1. Impact of climate change on buildings

To collect knowledge about the impact of climate change on buildings, the IPCC, IEA, and Google search services are consulted. Besides, the keyword “climate change” is searched in the literature database Science Direct on the links of Databases and Articles in the University

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of Gävle library. Summarizing the impact of climate change on buildings, this study divides the results into disaster and non-disaster.

 Part 2 Adoption of Building for Climate Change

To collect the measures of building adaptation to climate change, a methodology consisting of three phases was used.

The first phase(Limit the scope). As in section Part 1, considering the impact of climate change on buildings combined with the current development of building energy conservation and sustainable development, the study scope of building measures to cope with climate change is limited to A “disaster response measures”, and B “adaptation and mitigation” (this study mainly focuses on passive technology and energy-saving technology).

In the second phase (Literature survey), there are three steps. While most of the data in this study come from Science Direct (same as Part 1), there are also reports from IPCC, IEA, IEEE, Google search engine, Google Scholar, Wikipedia, China National Knowledge Infra- structure (CNKI), and Wanfang Data as well as the book Architectural Lighting [6]. The search terms for measures to deal with catastrophic extreme events are “extreme weather”,

“resilience enhancement” and “flood risk adaptation measure”, etc. A large number of search keywords are used for adaptation and mitigation measures, such as "passive house", "passive solar for building", "building envelope", "building energy efficiency" and "passive cooling".

The search language is mainly in English and a few in Chinese. While the latest literature on climate change and energy-saving technologies is searched, the year of publishing of literature for other types is not limited. The most relevant literature was selected according to the order of relevance. The literature is recorded in an Excel file, and each record is recorded according to the search term, document category, research technology, strategy, impact, method and result, abstract, document name, DOI, or website address. By reading the abstract of each document, the research technology, strategy, impact, method, and the result of the document can be collected. If the information is not clear in the abstract, then a thorough and detailed literature survey has been conducted. A total of 88 articles were retrieved, including 54 research articles, 12 review articles, 4 reports, 16 website articles, 1 short communication, and 1 book.

The last phase(Data collation). This paper summarizes the impact of climate change on buildings and the measures for buildings to deal with disaster weather. Nine categories of adaptation and mitigation measures are identified, which are: Exemplary Buildings, Building

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envelope, Passive ventilation, Lighting/Shading, Solar energy, Bioenergy, Dehumidifica- tion, Passive cooling, and Design Strategy.

This paper also has limitations. First, this research is based on the search database, mainly focusing on Science Direct. Second, the research language is mainly in English, and therefore, articles in other languages may have been omitted. Third, this research mainly con- centrates on passive energy-saving technologies and strategies, excluding other aspects like environment, health, policies, social and economic measures.

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3 Result

3.1 The Impact of climate change on buildings

There is no doubt about the impact of climate change on buildings. A paper from Cambridge University pointed out that climate change is expected to have far-reaching impacts on the building environment, although the exact extent of these impacts is uncertain, and there will be great differences between and within regions. Many buildings are vulnerable to climate change and extreme events. Impacts include increased rainfall, thawing of permafrost, more frequent wildfires, severe storms, and floods. This vulnerability is bound to increase without investment in resilience. The location of built assets is the key to their vulnerability.

The building sector itself is also facing a direct impact. Extreme precipitation will increase building delays and increase the cost. Climate change may also change the length of the construction season. The changing patterns of extreme weather events mean more reconstruction and restoration. The increase in the incidence and severity of heatwaves has an impact on architectural design, which may mean the need for different approaches from the current architectural design to that for new buildings. Higher temperatures will drive climate-related changes in energy demand[7].

Another report from Australia pointed out the main impacts of climate changes on buildings:

increased energy consumption due to higher temperatures; health effects of overheating;

stronger tropical cyclones and storms; and the effects of stronger winds, drier soil, more cracks, and ground movements on foundations and pipelines will increase the risk of damage;

increase in the damage caused by floods; increase in the risk of forest fires[8].

A review article from Qatar pointed out that climate change will have an impact on building energy consumption demand and building energy systems (distributed air conditioning system and power grid, district heating system, district cooling system). Buildings in hot and humid climates are most sensitive to climate change. The most extreme increase in cooling demand can be +150%for Sydney (Australia), while the most extreme reduction in the heating demand can be -264% for Tokyo (Japan) (depending on the location and characteristics of the buildings observed). In these climates cooling accounts for almost 90% of building energy demand, and the total building energy demand may increase significantly. The increase in total demand and the change of heating and cooling demand ratio will have a significant impact on the operation of the energy system[5].

Another review from Malaysia pointed out that climate change will have an impact on buildings energy demand, energy systems, and their internal services: the impact on building

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sustainability and indoor environmental quality, the impact on traditional HVAC systems, the impact on heating and cooling energy consumption, the impact on peak demand and energy consumption of building electricity, and that on building carbon emissions[9].

Generally speaking, the research literature on the impact of climate change on buildings in the future adopts the method of modeling, the modeling software including EnergyPlus[10- 13], HEED[11], TRNSYS[14, 15], IDA ICE[4], eXplainable artificial intelligence (Xai) model [16]. The CCWorldWeatherGen [5] tool is used to generate future climate profiles.

The energy use of buildings may have a net increase or decrease, and the impact will largely depend on the geographical location and type of building, and the availability of natural ventilation in some cities will be reduced [12]. Most studies affect overheating [14, 16-18], increased cooling loads, and reduced heating loads [11, 13, 15, 19, 20].

Several research articles from the United States pointed out that in addition to heatwaves [10, 13], the impact of climate change on buildings also includes the increase of power grid capacity demand[21]. Moreover, climate change will also bring heat island effects (UHIs ) [22](UHIs are originated by heat generated in urban environments that is entrapped by urban structures being aggravated by greenhouse gases and the lack of green spaces), an increase in humidity. The power grid is vulnerable to extreme events, affecting the energy supply[10]. Unless there are significant changes in the design, construction, and operation mode of buildings in the next few decades, the operation cost of buildings will rise sharply, and the already tense energy supply system may be interrupted[23].

A research article from China pointed out that due to the maximum warming, the large de- creasing trend magnitude of Heating Degree Day (HDD) occurred in the high terrain and high latitude regions there. So still have a relatively large energy consumption demand for heating in winter in the Tibetan Plateau and northeast severe cold areas [24]. According to the literature from Hong Kong, the subtropical climate was estimated for two emissions scenarios(The Low forcing, rapid transition to a service and information economy, the mid- 21st century, the global population reached a peak and then decline, the introduction of clean and resource-saving technology, emphasis on the economic, social and environmental sustainability of Global Solutions. The medium-forcing, Very rapid economic growth, the same demographic trends as in the low-forcing scenario, convergence between regions with increased cultural and social interaction, and technological focus on the balanced mix of fossil and non-fossil energy resources), compared with 1979–2008 and 2091–2100, the average annual building energy consumption will increase by 6.6 and 8.1% [25].

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A research paper from Malaysia in the investigation of the climate-change impacts on the Air-Conditioning and Mechanical Ventilation(ACMV) systems in the office building. The research pointed out that climate change will affect the efficiency of existing systems and lead to a decline in the durability of the existing system[14]

Research from Lithuania points out that climate change leads to a decrease in heating days, resulting in a decrease in heating load. Although the cooling load increases slightly, the heating load dominates. The total energy consumption of buildings will be reduced[11].

Research from Italy pointed out that old buildings will consume more energy due to climate change, especially due to the decrease in HVAC equipment efficiency. The increase in cooling energy usage in a warming climate counteracted the reduction of the heating energy usage resulting from warming [4].

In general, the impact of climate change on buildings can be divided into disaster extreme weather conditions and non-disaster conditions according to the severity. Disaster extreme weather such as typhoons, floods, blizzards, and freezing rains will cause interruption of power supply, damage to buildings, abnormal operation of buildings, and casualties. It is characterized by sudden occurrence, short time, and great loss. Non-catastrophic impacts such as temperature rise, overheating and humidity increase will go beyond the original design scope of buildings, affect the comfort of residential use, bring health impact to human beings, accelerate the aging of buildings and increase energy consumption and carbon emissions, thus aggravating the greenhouse effect.

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3.2 Adaptation of building for climate change

The building sector accounts for a huge share of carbon dioxide emissions, and residents' expectations of comfort are also rising. This means huge energy-saving opportunities, and it has become a high-priority area of climate change. Buildings should adopt the methods of adaptation and mitigation to deal with climate change. Because the disaster effects of extreme weather are the result of climate warming, we can only take adaptive measures. In terms of the impact of non-disaster situations, we should adopt adaptation and mitigation strategies, that is, sustainable development measures.

3.2.1 Methods for dealing with disaster-type extreme weather

The impact of disaster extreme weather on buildings is mainly on the power supply. Most of the solutions are discussed from the perspective of power system engineering.

From the point of view of power system engineering and extreme weather events, a review article summarizes the research status of power grid resilience. Also introduced the strategies of grid resilience enhancement include: enhancing grid physical resilience (Vegetation management; Selective underground laying; Material upgrading and revitalization; Elevated substation and water barrier; Substation relocation and line re-routing) and Enhance grid operation capability (Emergency generators and mobile substations; Microgrid and distributed energy; Spare parts and maintenance personnel management; Grid monitoring system based on extreme weather events; Regulations and design standards upgrade).[26].

A research paper from the United States points out that an effective flexible power measure includes: (1) Elevating substations and system control rooms; (2) Building floodwalls for power stations and infrastructure that cannot be elevated; (3) Replacing wooden poles with metal, concrete, or composite poles that better resist high winds or wildfire; (4) Installing supporting guy wires or other structural supports to vulnerable poles; (5) Upgrading transmission and distribution lines with materials that can better resist high winds, debris, and wildfires;(6) Undergrounding key power lines; and, (7) Maintenance activities, such as ag- gressive vegetation management[27].

A research paper from China proposes an active operation framework based on deep reinforcement learning (DRL) is proposed, which can effectively improve the resilience of the distribution system in extreme weather. The performance of the framework shows that it can keep the load running when the line, distributed generator (DG), load, and other components fail. The framework can learn from decisions adaptively to reduce the damage of similar events to the system in the future.[28].

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In a research paper from China, an effective framework for ice disaster resilience enhancement is proposed. It is based on a series of system-level and component-level indicators, covering all stages of the ice disaster process. Before the failure occurs, the framework can help to locate the weak link and guide the preventive measures. During the ice disaster, the framework can guide the update of de-icing sequence in real-time, to minimize the impact of the ice disaster on the transmission system. After the disaster, the optimal repair sequence can be worked out by using this framework, so that the system can recover to its elastic state as soon as possible. The results show that the framework can improve the recovery ability of the system correctly[29].

Solar panels can provide power to affected communities during blackouts. A research paper from the United Kingdom has successfully demonstrated the ability of the coupled FSI-BES method to evaluate the structural flexibility and energy of a photovoltaic system frame for extreme weather analysis of a low-rise residential building in Tacloban, Philippines. The paper suggests that the PV system should be installed on a 26.5 degree pitched roof to provide the best balance between power generation and structural flexibility. It is also suggested that urban planners can correctly plan the direction of houses on the known path of the typhoon, to minimize the damage and obtain the highest solar power generation potential[30].

For flood areas, a study from Malaysia assessed all construction costs and environmental emissions in flood areas when there are no floods as well as after restoration when floods hit buildings to determine the feasibility of restoration. Under the conditions of non-flood, low flood, and high flood, five kinds of building materials, including common brick, concrete block, steel wallboard, timber, and precast concrete frame, were evaluated by life cycle assessment (LCA) and life cycle cost assessment (LCC). Due to more cost and environmental emission, wood is not ideal as building materials in flood areas, while brick and other alternative materials have better functions in slowing down global warming and reducing costs[31].

Generally speaking, the disaster extreme climate has the characteristics of sudden, destruc- tive, and long recovery time. The response measures for buildings are to improve their reliability, resilience, sustainability, and robustness.

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11 3.2.2 Adaptation and Mitigation 3.2.2.1 Exemplary building

Passive House

Passive housing standard[32] is the most stringent heating standard. It usually needs a high- performance exterior protection structure, high-performance doors, and windows, no thermal bridge, good sealing, coupled with heat recovery, mechanical ventilation to ensure indoor air quality, without active heating, heat comes from sunlight, residents, and indoor daily equipment. According to the standard, the energy consumption of the heating load (assuming that the indoor temperature is uniform at 20 ℃ ) shall not exceed 15 kWh/m²/year regardless of the climate. In 2012, about 57 000 buildings in 31 European countries met the standard. As early buildings in Europe had almost no insulation layer, the heat load in southern Europe was reduced by 6-12 times, and in cold climate regions, the heat load was reduced by 30 times at most[3].

Zero energy building

Zero energy building (ZEB), also known as net-zero energy (NZE) building or zero net energy (ZNE) building, has the European Union had a similar concept called near-zero energy building (NZEB). Terminology often varies by country, institution, city, town, and report. It refers to the total amount of energy used by buildings every year, which is equal to the amount of renewable energy generated off-site by renewable energy using a heat pump, efficient windows, solar panels, heat insulation, and other technologies. The goal is that the greenhouse gas emissions of these buildings are lower than those of similar non-net- zero buildings. But sometimes it also reduces energy consumption and greenhouse gas emissions elsewhere. The driving force of zero energy buildings is not only the hope of less impact on the environment but also driven by capital [33].

Green building

Green building (also known as green construction or sustainable building) refers to the whole life cycle of the building, from planning to design, construction, operation, maintenance, renovation, responsible for the environment, and saving resources of the structure and application process, and demolition [34]. The practice of green building is slightly different from zero energy building because it takes into account all environmental impacts, such as material use and water pollution, while the scope of zero energy building only includes building energy consumption and the ability to produce equal or more energy from renewable energy[33].

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Positive-energy building

The positive-energy building (PEB) is an extension of zero energy consumption building. It uses recycled building materials as far as possible and uses new technologies and products such as solar panels to realize the utilization of clean energy and renewable energy. It not only saves energy and carbon but also generates electricity to make money[3]. In PEB the power generation is not only higher than the energy required for building operation, but also can charge electric vehicles.

According to the standards of the above demonstration building, if the building is not heated to a comfortable temperature at present, the passive building standard can help to achieve comfortable conditions and reduce the use of absolute heat. The use of cooling energy is growing rapidly in many areas. As long as we pay proper attention to the useful parts of local design and combine them with modern passive design principles, we do not need mechanical air conditioning. Evaporative cooling or mixed evaporative/mechanical cooling strategies can be implemented in areas with large diurnal or seasonal temperature variations or dry areas. If the insulation level of passive residential standard meeting the thermal demand of southern Europe is combined with the above strategy, the thermal load can be reduced by 6-12 times (from 100-200 kWh/m²/year to 10-15 kWh/m²/year), and the cooling load can be reduced by 10 times (from < 30 kWh/m²/year to < 3 kWh/m²/year) [3].

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13 3.2.2.2 Building envelope

A building envelope is a physical partition between the conditional and unconditional environment of a building, including resistance to air, water, heat, light, and noise transmission [35]. The physical components of the envelope include the foundation, roof, walls, doors, windows, ceiling, and their associated barriers and insulation.

A field study from Iran reviews existing building maintenance techniques. It is pointed out that the most important envelope energy-saving technologies include: 1. Deeply cover glasses; 2. Advanced, high operation and "light" covering; 3. The low labor intensity of gas seal and low cost of verification test; 4. Low cost automatic and effective shading and glazing;

5. More robust and cheaper reflective roof elements and reflective layers [36].

A research paper from Morocco proposed that phase change material (PCM) should be applied to hollow brick (widely used in Moroccan buildings) to improve the thermal performance of external walls, to cope with the severe weather conditions in some areas of Mo- rocco; During the summer solstice, the ambient temperature is 45℃ during the day and night 25℃. The results show that the application of phase change materials in building bricks can stabilize and reduce indoor temperature fluctuation. [37].

Another field study from Australia conducted a numerical simulation of a single-story residential building without an active air conditioning system. The results show that PCM renovation can effectively reduce the risk of indoor heat stress. Under extreme heatwave conditions, choosing PCM with a better ventilation design can shorten the severe discomfort period by 65%, which has significant advantages in improving the health and comfort of residents. Among them, the selection of appropriate phase transition temperature and PCM dosage is the key to the effective application[38].

One field study from Norway conducted an economic analysis of Building-integrated photovoltaics (BIPV) systems in 30 countries and calculated Net present value (NPV), the payback period (DPP), and Internal rate of return (IRR) of BIPV as the whole building skin material. The results show that it is feasible to use the BIPV module instead of traditional facade material for building external surfaces [39].

Research from Italy shows that adding ceramic panels as an external coating(see Fig 2) reduces heat loss by 42% compared with traditional wall structures without any insulation

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materials. For the existing houses with an internal insulation layer or coating, adding a ceramic plate can reduce the heat change of the internal insulation layer after installation and construction by 31% and 40% respectively[40].

Fig.2 External ceramic panels applied on a façade [40]

Research from Morocco studied clay-sawdust composite as an exterior wall enclosure. The results show that the sawdust-clay composite can reduce the energy consumption of con- ventional and traditional residential buildings by 21% and 5.3% respectively[41].

Research from Ghana shows that mixing sand concrete blocks with existing bio-based local materials, especially treated sawdust and palm fibers, minimizes their thermal conductivity.

The results show that the density and thermal conductivity of sand concrete is reduced by adding bio-based materials into the sand concrete, thus the heat transfer load of the wall is reduced. The composite material of 70% sand concrete and 30% treated palm fiber (P30) can save 453.4 kWh of electricity per year(In tropical climates,Total wall surface area 66 m²) [42].

Research from the Netherlands described a study of building facades in hot climate conditions in Dubai. The facade was constructed with bio-based external cladding in line with the principle of circular economy, including toilet paper, grass, reed, recycled textiles, waste from drinking water treatment, bio-based polyester resin, and other materials. The results show that the facade helps to reduce the temperature in the apartment, especially at the hottest time of the day. In addition, the facade is a promising choice for hot summer and mild winter climates, because it helps to reduce energy consumption and the impact of building materials on the environment [43].

Research from Switzerland focused on energy-saving mitigation measures to improve indoor thermal comfort during heat waves by using hygroscopic materials. The study established a model and applied it to indoor thermal conditions in hot summer in Zurich, Swit- zerland. The results show that the indoor temperature cannot be accurately simulated by

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neglecting the water transmission in the enclosure. Due to the urban heat island effect, night ventilation is not enough to cool the indoor environment during the urban heatwave. To reduce indoor thermal stress, the potential of pre-cooling and moisture-desorption cooling of hygroscopic materials was studied. The average operating temperature during the heatwave can be reduced by 0.43℃before the heatwave starts. The desorption cooling of hygroscopic material can reduce the average working temperature by 1.31℃ during heat waves. The combination of these two mitigation measures can lead to enhanced passive cooling. It has great potential to use the desorption of hygroscopic materials to reduce the thermal stress in the heatwave and minimize the building energy consumption[44].

A case-based reasoning (CBR) decision support model for the preliminary design of the building envelope is established in research. Taking the case base of 100 green public and commercial buildings as an example, the model is developed. An experiment is carried out on a test case to verify the method and usability of the model. Taking 25 green public buildings as examples, the effectiveness of the model is verified. The results show that the accu- racy of the CBR model is 84% when considering the cold and hot demand of the building envelope. In short, the CBR model proposed in this research is hopeful for improving the efficiency of envelope design of public and commercial buildings and reducing the depend- ence on expert participation [45].

Most literature points out that it is helpful to reduce energy consumption to maintain and encourage the use of building envelope with thermal elastic change, and to adopt PCM and bio-based materials.

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16 3.2.2.3 Passive ventilation

Passive ventilation refers to the process of supplying and discharging air to indoor space without using a mechanical system. It refers to the pressure difference caused by natural forces, external air flows to the indoor space. There are two kinds of natural ventilation in buildings: wind-driven ventilation and buoyancy ventilation. Wind-driven ventilation is generated by the different pressures of the wind around the building or structure, and the airflow formed around the building through the opening. Buoyancy-driven ventilation is due to the directional buoyancy caused by the temperature difference between indoor and outdoor [46].

A research article from Egypt takes the solar chimney (A solar chimney is a way of improving the natural ventilation of buildings by using convection of air heated by passive solar energy.

A simple description of a solar chimney is that of a vertical shaft utilizing solar energy to enhance the natural stack ventilation through a building[47]) as the research object, adopts the passive solar energy technology combined with water heater and phase change material(Fig3), and combines the short wind tower to cool the low-energy building in the hot and dry climate. The results show that the minimum air velocity in the chimney is 0.69 kg/s after sunset. In addition, the combination of solar chimney and PCM with cooling tower reduces the indoor air temperature by 8-4k in the daytime and at night respectively. The research results provide reference information for the integration of this new type of low energy consumption compact passive air cooling and water heating system into high-rise residential projects in the hot and dry climate of Egyp [48].

Fig3 Solar Chimney integrated with solar water heater [48].

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A review article reviews the traditional and modern technology of wind tower(Wind tower is used to create natural ventilation and passive cooling in buildings[49]), emphasizes the importance of wind tower, and deeply discusses the scheme of passive cooling system replacing high energy consumption mechanical ventilation system. The study emphasizes that different cooling technologies can be integrated with the wind tower to improve its ventilation and thermal performance(see Fig.4) [50].

Fig. 4. Concept design of a passive wind tower integrated with different cooling devices [50]

Another review from Greece pointed out that the building design of night ventilation can reduce the energy consumption of air conditioning by about 20-25%. The application of night ventilation technology in residential buildings may reduce the cooling load by nearly 40 kWh/m²/y. The effectiveness of night ventilation technology depends on the climate conditions, microclimate, building characteristics, and the location at that time. Especially in arid areas where ventilation during the day is not enough to ensure thermal comfort, night ventilation is effective[51].

In order to reduce the energy consumption of air conditioning, passive ventilation is necessary. And passive ventilation can play a major role in NZEBs.The ventilation method without mechanical intervention and therefore without energy is called natural ventilation. To reduce building energy consumption and carbon footprint, sustainable ventilation technology is proposed. Such as wind tower and night ventilation technology.

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18 3.2.2.4 Lighting and shading

In summer, the windows are preferably protected from the influence of solar radiation, to reduce the cooling load caused by solar radiation, while in winter, maximum solar radiation is allowed. This section collects the main methods of building lighting and shading.

In the book Architectural Lighting, the basic knowledge of building lighting is introduced comprehensively and deeply. This book focuses on natural light and artificial lighting, and abundant charts and examples provide the basis for understanding lighting space[6].

A study from Europe focuses on the control methods that can not only protect the occupants from direct sunlight but also maximize the penetration of natural light in the building according to the preferences of the occupants while reducing the power consumption of lighting and cooling. All control and/or natural light guidance systems and/or strategies ensure that sunlight enters the building (e.g. Fig.5 Light deflection using prismatic glazing), thereby reducing power consumption for lighting and cooling. At the same time, they improve the thermal comfort and visual comfort of building users [52].

Fig.5. Light deflection using prismatic glazing [52].

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A study from Brazil compared three main lighting technologies: incandescent halogen lamp, compact fluorescent lamp (CFL), and LED (light-emitting diode). The results show that the LED lamp is the best lighting choice [53].

In addition, a report from the UK pointed out that energy-saving lighting products are par- ticularly suitable for retrofitting applications due to the minimal damage to building structures caused by energy-saving lighting products and the latest improvements in LED technology. Compared with traditional commercial technology such as halogen lamps, the energy-saving rate of LED is about 80%. The service life of LED can reach 50 000 hours, while that of a halogen lamp is 2 000 hours. It is equivalent to replacing 25 bulbs, plus the cost of hiring maintenance engineers [54].

A review article from Malaysia summarizes the existing shading technology. The shading system is divided into passive, active, and hybrid systems. In the passive fixed shading system, the egg-crate(see Fig.6.) device is considered to be the best device to improve solar and thermal performance [55].

Fig.6. Different fixed shading devices[55].

A review study from Turkey introduces shading technology in terms of fixed shading devices and mobile shading devices. It is pointed out that the Venetian blinds are one of the most commonly used sunshade devices studied among other types. And blinds are one of the most commonly used shading devices [56].

Future forecast:1) The development of interior shading strategy, material use, and comfort parameters should be dealt with deeply.2) In the design of the shading device, the data of

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some positions affected by microclimate conditions should be collected accurately.3) Con- sidering the energy consumption of buildings, the combination of sunshade and building and the use of movable type should be the priority of future design.4) The function of the building and the habits and preferences of the residents have an important impact on the energy consumption of the building. Before the construction, the model should be simulated and optimized according to the required parameters to satisfy future users.5) In the hot, dry, hot, humid, and extremely hot climate area, adopting an appropriate sunshade type can only reduce the cooling load of the building[56].

A research article from Argentina pointed out that shading is considered to be one of the most effective design strategies to deal with climate change in future buildings [13].

An article from Korea studies the reasonable external shading in the design of high-rise residential buildings. Through the energy-saving performance, economic feasibility, and applicability test, it is verified that the horizontal overhang and vertical panel were verified to be the best shading types to use in high-rise residential buildings. The research can provide basic information for reasonable external shading planning in high-rise residential design.

The study also pointed out that in the future, based on the review of materials and various designs, it is necessary to carry out follow-up research on reasonable installation modules and selection criteria [57].

By using LED lighting and reasonable use of a sunshade, the effect of solar radiation can be effectively reduced and comfort can be provided.

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21 3.2.2.5 Solar energy

Solar energy is the radiant light and heat from the sun, using a series of constantly developing technologies, such as solar heating, photovoltaic, solar thermal energy, solar buildings, mol- ten salt power plants, and artificial photosynthesis. Solar energy is an important source of renewable energy, and its technology is widely described as passive solar energy or active solar energy, which depends on how they capture and distribute solar energy or convert it into solar energy. Active solar technology includes the use of photovoltaic systems, concen- trated solar energy, and solar hot water to use energy. Passive solar technology includes orienting buildings toward the sun, selecting materials with good thermal quality or light dispersion, and designing spaces with naturally circulating air. A lot of solar energy makes it an attractive source of electricity. In its 2000 world energy assessment, the United Na- tions Development Program found that the annual potential of solar energy is 1 575- 49 837 exajoules (EJ), This is several times the world's total energy consumption, which was 559.8 EJ in 2012 [58].

In a study from Denmark, solar photovoltaic-thermal (PVT) panels are integrated with heat storage tanks to meet a large part of the building's heat and power needs. The system does not have any batteries, which greatly reduces the cost, and can interact with the local heating network and power grid in two directions, with strong compatibility. The results show that the system not only provides domestic hot water buildings throughout the year but also generates 402.8 m³ of 40 ℃ hot water, which is sold to the local ultra-low temperature central heating network. The electricity purchased from the grid is 2 083kWh, while the electricity sold to the grid is 1 938 kWh, so the annual electricity cost of the building is almost compensated [59].

In another field study from Brazil designed the lab as a zero energy building (ZEB). Photo- voltaic systems were installed on the roof and facades of the lab, and a garage, an electric bus stop, and a shed nearby. The results show that the total photovoltaic power generation is 111kWp, which can meet 148% of the building energy demand. If the system has been operating at its best performance, it can generate 38% more energy, which means 134% of the building and e-bus consumption. Therefore, the laboratory can be regarded not only as a ZEB but also as a positive energy building (PEB) [60].

Another study from Brazil pointed out that a photovoltaic system can be used in positive energy buildings (PEB), where the power generation is higher than the energy required for building operation, including charging electric vehicles. In this study, a comparison between

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Building-integrated photovoltaics (BIPV) and ground-mounted (GM) photovoltaic (PV) systems is made. The results show that the BIPV system has a higher average yield and performance ratio (PRs) than the GM system,the main reason for that was the incidence of shad- ings. In conclusion, photovoltaic modules can be more freely used as building skin and/or materials in building integration, because the BIPV system can perform well even in the case of unsatisfactory location and partial shielding [61].

One field study from China pointed out that the five factors affecting the efficiency of solar power generation are: solar radiation intensity, payback period, solar radiation rate, installation area, and water supply temperature [62].

Solar thermal collectors are cheap, practical, and widely used options. According to a research article from Iran, the average total cost of using solar collectors has been reduced by about 13%, and the use of solar collectors is the best alternative to the use of natural gas [63]. In another research paper, three kinds of passive technologies are adopted for the net- zero energy building (NZEB), namely: 1, Earth-Air Heat Exchanger (EAHE), 2, Under- ground Tank (UNT), and 3, Solar Thermal Collector. And the size of the building is 4.7×3.7×2.8m³(see Fig.7). The results show that under the climate conditions of Oran, Algeria, the combination of the three systems meets all the requirements, reaching 131%.

Combining the three systems at the same time saves 37.9 euros (or 232.8 kWh of energy demand) and reduces CO2 emissions by 21.1 tons [64].

Fig.7. Experimental building[64]

In another field study from India has developed a building integrated passive solar technology (BIPSET) for power generation, water supply, and air ventilation. The system is com- posed of solar photovoltaic (PV) and solar distiller, which is integrated with the chimney.

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The experimental analysis shows that the average air exchange rate in the room is 12 times per hour by using the heat energy obtained by the solar photovoltaic in BIPSET. The average daily air inlet velocity is 0.14 M/s, which meets the international standard ISO 7730:2005.

The BIPSET photovoltaic system is more efficient than a stand-alone photovoltaic system.

From the perspective of economic analysis, considering that the government subsidies for photovoltaic panels are 30%, the unit cost of chimney solar photovoltaic power generation is reduced by 18%. The integrated system is technically and economically feasible and environment-friendly [65].

One field study from Lithuania, using sun thermal collectors and solar PV, can transform the Soviet-style apartment(e.g.:Khrushchyovka is a type of low-cost, concrete-paneled or brick three-to-five storied apartment building which was developed in the Soviet Union during the early 1960s[66]). The result shows that the energy-saving transformation can cover 61.7% of electricity demand per year [67].

Another research from China, an ejection compression refrigeration cycle system based on partial solar coupling is studied. The results show that the partially coupled ejector refrigeration cycle has obvious advantages in electric coefficient of performance, solar coefficient, thermal coefficient of performance, and total primary energy, which is helpful to reduce carbon dioxide emissions. The significant difference of auxiliary heat between the partially coupled ejection compression refrigeration cycle and the traditional ejection compression refrigeration cycle leads to a significant primary energy-saving effect of the partially coupled cycle. It shows that the application of the partial coupling cycle in modern urban multi-story buildings has significant advantages and good applicability [68].

Another field study from Italy proposed a solar absorption chiller, but its application in a residential area is still in the early stage. The energy model is established in TRNSYS. It is proved that the system can meet the energy demand of cooling and domestic hot water, and the use of non-renewable energy is very limited. After the optimization of the system, it is possible to achieve a high renewable energy ratio as high as 83% [69].

One field study from Malaysia discusses the latest development, practical technology, and applicable technical indicators of solar water heaters (SWHs) with and without phase change materials by using the 4E (energy, exergy, exergy economy, and environmental economy) analysis method. The research results show that the combination of solar water heaters and PCMs can greatly improve the energy efficiency, exergy efficiency, and energy recovery period [70].

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In another field study from Germany provides a structured overview of a wide range of technical design options for BIPV systems, classifies and analyzes them, and compares various available solar cell technologies. At the same time, it is pointed out that the BIPV module can be produced by a highly automated customized production line, which provides great potential for local value creation. The conclusion shows that crystalline silicon solar cell technology has the biggest advantage in BIPV application due to its long service life, price pressure, availability, and rapid technological progress. Two basic module-level design options are studied in detail: using PV cells as the basic elements of the pattern, and using color to hide PV cells. It can integrate the whole building with the surrounding environment.

With the given technical design options, the BIPV system can be customized for various construction projects and make a significant contribution to renewable energy systems [71].

Another effective solar technology is the TROMBE wall(see Fig.8). It is a massive Equator- facing wall that is painted a dark color to absorb thermal energy from incident sunlight and covered with a glass on the outside with an insulating air gap between the wall and the glaze.

Sunlight first strikes a solar energy collection surface that covers thermal mass located between the Sun and space. The sunlight absorbed by the mass is converted to heat and then transferred into the living space[72].

Fig.8. Trombe Wall[73]

This section mainly collects the active solar literature, including the use of solar collectors, solar photovoltaic, and other devices to provide heat, power, ventilation, cooling, clean

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water, and other functions for buildings. Due to its easy access and environmental benefits, solar energy has become effective alternative energy for fossil fuels and has been promoted all over the world.

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26 3.2.2.6 Bioenergy

Anaerobic digestion is considered to be one of the most energy-saving and environmental protection technologies in bioenergy production. This section collects the application of bioenergy.

Bioenergy is made of biomass or biofuel. Biomass energy is any organic matter that absorbs sunlight and stores it in the form of chemical energy. Examples are wood, energy crops, and waste from forests, yards, or farms. Since biomass can be directly used as fuel (such as log) technically, some people can use the terms biomass and biofuel interchangeably. Usu- ally, the term biomass energy only refers to the biological materials used to make fuel. The term biofuel is usually reserved as a liquid or gaseous fuel for transportation. The US energy information agency(EIA) follows this naming convention. The IPCC defines bioenergy as renewable energy. IEA defines bioenergy as the most important renewable energy. The IEA also believes that the current deployment speed of bioenergy is far lower than that required under the low-carbon scenario, and there is an urgent need to speed up the deployment speed. Researchers dispute the idea that using forest biomass as energy is carbon neutral[74].

A literature review of net-zero energy buildings pointed out that biogas can be produced from waste, residue, and energy crops, which is important renewable energy. In addition to being used in cogeneration systems, biomass can also be used for heating or cooling without power generation, using biomass boilers, absorption or adsorption chillers, or gas- driven heat pumps [75].

A research paper from Germany developed and tested a control system that allows optimal heat and microalgae production in the bioenergy facade to be maintained and used to provide hot water and heating for residential buildings. The bioenergy facade is an innovative technology. By integrating bioreactors into the facade of buildings, it combines heat and biomass production with minimum horizontal space requirements. The technology uses microalgae to convert solar radiation hitting the bioenergy facade into biomass through photosynthesis. The unused radiation of algae is converted into heat - similar to the classical solar thermal system. The heat is removed from the bioenergy facade through heat exchangers for heating and hot water supply. The results show that biomass energy buildings can be well integrated into the city, and the city can be transferred from the place with rich resource consumption to the place with resource production through the simultaneous generation of heat and biomass [76].

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A research paper from Turkey points out that microalgae have great potential to reduce carbon dioxide emissions throughout the life cycle of buildings by improving energy efficiency and actively capturing carbon dioxide. The use of closed microalgae photobioreactors as building components has the additional benefit of being an effective thermal insulation system. In addition, microalgae can provide a dynamic appearance and life dynamic system, and can also be used as an adaptive sunshade [77]. Below in Fig.9 is a Bioreactors application facade in Hamburg, Germany[78].

Fig.9. Bioreactors application facade in Hamburg, Germany[78]

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28 3.2.2.7 Dehumidification

This section describes the passive dehumidification technology.

A field study from Japan has carried out experimental research and simulation analysis and developed an efficient air conditioning system that can separate latent heat from sensible heat by using fiber insulation material with excellent moisture regulation performance.

Based on nonequivalent thermodynamics, the basic principle of an intelligent skin system based on thermodynamic potential is studied, including passive dehumidification and solar energy collection. The results show that the sensible heat and latent heat can be significantly reduced by using renewable energy to run the system[79].

Another field study from China set up an experiment in which liquid desiccant was used to act as a hygroscopic device when flowed down a vase or sphere, absorbing moisture at high humidity and releasing moisture at low humidity. The results show that the factors affecting the dehumidification capacity of the indoor passive falling film liquid dehumidifier are as follows: solution type, indoor relative humidity, indoor air temperature, and solution flow rate. The indoor relative humidity was below 70% in the first two hours [80].

One field study from Lebanon simulated a novel hybrid cooling system for hot and humid climates, which integrated a phase change thermal reservoir with a melting temperature of 25℃. Cooling air supply, personalized evaporative cooler (PEC) to provide cooling for the occupants. The supply air humidity is controlled by a solid desiccant wheel, which is regen- erated by an auxiliary heater and supplemented by a TROMBE wall[72]. The indoor relative humidity should be controlled so that it does not exceed the maximum allowable limit, and finally, the acceptable thermal comfort level can be achieved [81].

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29 3.2.2.8 Passive cooling

This section describes passive cooling technology.

A field study from Morocco used passive technology on the roofs of three outdoor labora- tories in a hot semi-arid climate, namely white paint, shading, and insulation. The results show that the performance of the painted roof is the best, and the ceiling temperature is reduced by 13.0℃. The heat flux through the roof slab is reduced by 66% [82].hot semi- arid

A research paper from Portugal conducted experiments on four passive cooling technologies for prefabricated buildings, including shading, natural ventilation, cold painting, and increasing gypsum thickness. The results show that the increase of heat can be prevented by shading and cooling paint, and the indoor high temperature can be reduced by increasing the thickness of gypsum plaster and natural ventilation. By combining the best solution of each technology, the thermal comfort of occupants can be achieved in almost all annual residence periods in Nairobi climate [83].

In the hybrid cooling system studied in the previous section [81], the thermal comfort of the occupants was maintained between neutral and slight discomfort to achieve an acceptable level of thermal comfort. The results showed that compared with traditional air conditioning, the TROMBE wall could save 55% of the thermal energy consumption of the proposed system during the whole summer and reduce the total energy cost by 87%.

A review article from India summarizes the classification, working principle, application, and latest progress of passive refrigeration technology, and analyzes the influence of building cooling load, indoor temperature, and other important parameters on the performance of passive refrigeration technology, the research can guide architectural designers, architects, and researchers engaged in energy-saving green building [84].

A review from Malaysia introduces passive cooling technology for reflective and radiant roofs. It is pointed out that the efficiency of passive cooling depends on the type of building, occupancy pattern, and climatic boundary (e.g. temperature, relative humidity, wind speed, and direction), which are different during the day and between one area and another. There- fore, to effectively improve the heat dissipation of buildings by natural means, designers should fully understand the physical characteristics of buildings. Therefore, it is found that the limitations of assessment tools and the lack of information from designers and building

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users are the main reasons for the non-adoption of passive cooling strategy in tropical houses [85].

A review article from Greece introduces three kinds of passive cooling technologies, earth- to-air heat exchangers (East), which are very mature and efficient. As a passive cooling technology, evaporative cooling has been widely used in building environments [51].

One study used PCM and optimized night ventilation. The melting temperature of phase change materials in office buildings under different climatic conditions was optimized. It is found that a lot of cooling energy can be saved when PCM is ventilated and charged at night, especially when some specific natural ventilation control strategies are used (by opening windows). The results show that under the condition of high temperature and drought, the effect is only equivalent to the use of natural ventilation. On the other hand, under temper- ate conditions, the effectiveness of PCM is increased from 3.32% to 25.62% by combining the PCM passive system with night ventilation. When PCM temperature control ventilation is used, it can be further increased to 40%. It can be said that intelligent control ventilation can bring considerable energy saving [86].

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31 3.2.2.9 Design strategy

This section collects strategies related to building energy conservation.

A field study from Hong Kong shows that in the tropics, external insulation is ineffective in mitigating the expected growth in building energy use caused by climate change. It would be a better choice to control the heat of the sun through the windows. The paper also puts forward the strategy of energy-saving and mitigation potential. Reducing lighting load density (LLD) will have good energy-saving and mitigation potential because it reduces the power consumption of electric lighting and air conditioning. The LLD can be reduced to about 13 W/m². Adjust the summer setpoint temperature (SST) to 25.5℃or higher. Or for cooling devices, increasing the coefficient of performance (COP) value or higher will have high energy saving and mitigation potential, which can be easily applied to new and existing buildings[25].

In another field study from Australia proposes a new simulation-based optimization method, which uses the climate model and ant colony optimization method to compare energy optimization design under current and future climate conditions. Different optimal architectural designs can be obtained by optimization under future climate conditions [87].

One field study from China reviews the thermal performance of precast walls, including investigations of two common structures, precast concrete sandwich walls, and lightweight steel frame walls. The applicability and limitation of the methods often used to determine the thermal resistance of the two walls are introduced. This paper also presents a literature review on the impact of prefabricated buildings on China's emission reduction. Compared with traditional buildings, the contribution of prefabricated buildings to China's emission reduction has been recognized. People also recognize the potential in building energy efficiency and waste reduction. The conclusion is that prefabrication is generally considered to be a more sustainable approach in the field of architecture. Through life cycle analysis and thermal performance evaluation, the energy-saving potential of prefabricated parts is proved [88].

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4 Discussion

This study is a wide scope. The search of this study mainly focused on the Science Direct database. This paper describes the existing literature on the impact of climate on buildings and building adaptation measures to climate change. Search terms related to building energy are used, covering all aspects as far as possible. But some technologies are not been found by using the search terms.It needs to be used separately for retrieval. Such as the Internet of things, big data, the application of green plants in building envelopes.

According to the severity, the impacts of climate change on buildings are divided into disaster extreme weather conditions and non-disaster conditions. Then the corresponding search strategies and technologies are proposed. Strategies and techniques for dealing with disaster weather can help reduce losses and recover as soon as possible. In response to the situation of non-disaster, conditions are introduced in nine aspects. According to the local climate, geographical characteristics of the building, comprehensive development of passive technology and strategy can meet or close to meet the needs of energy conservation and comfort. However, whether it can achieve the effect of curbing climate warming, there is no research to confirm this. We can only do our best to slow down the increase of carbon dioxide concentration in the atmosphere. To decrease the negative impact of climate change.

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5 Conclusion

5.1 Study results

Climate change on buildings has a profound impact. This study searched a large number of literature about the impact of climate change on buildings, and the technologies and Strate- gies of buildings to cope with climate change. Most studies have found that climate change will lead to an increase in temperature and humidity, resulting in overheating in buildings, increasing the cooling load of building energy consumption, and reducing the heating load.

In addition, the frequency of extreme weather events will increase, and the most direct impact on buildings is a power failure. According to the severity, this study divided the impact into disaster extreme weather conditions and non-disaster conditions. Then according to the two classifications, the relative solutions and strategies are given. In response to disaster extreme weather conditions, the main strategy is to improve reliability, resilience, sustainability, and robustness, it can help reduce losses and recover as soon as possible. In response to the non-disaster situation, we mainly consider the strategies of adaptation and mitigation, and sustainable development. In this study, passive energy-saving technology is mainly found. And according to the classification of "Exemplary building ", "Building envelope", "Passive ventilation", "Lighting/Shading", "Solar energy", "Bioenergy", "Dehu- midification", "Passive cooling" and "Design strategy", the paper introduces them. Accord- ing to the local climate, geographical characteristics of the building, we can develop comprehensive passive technology and strategy to meet or close to meet their own needs for energy conservation, emission reduction, and comfort. This study can provide a technical and strategic basis for building reconstruction and new construction under climate change in the future.

5.2 Outlook

1. Response, wildfire, storm disaster impact on the building can be supplemented in the future.

2. The supplement of related technologies and strategies will be a part of our future research, such as the Internet of things and big data.

3. In this study, the building envelope mainly focuses on building materials, and the technology of green plant covering on the outer surface of the building has not been involved.

It can be used as a supplement for future research.

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34 5.3 Perspectives

Through the use of passive strategies and technologies and renewable energy, new and trans- formed buildings can save energy and environmental protection, reduce carbon emissions, and even become positive energy buildings to provide power for the grid. It has both environmental and economic benefits. This is crucial. More specifically, from the perspective of the sustainable development goals set by the United Nations, the measures for buildings to cope with climate change will help to achieve the goals 6: clean water and sunshine, 7:

sustainable and clean energy, 9: industry, innovation, and infrastructure, 11 sustainable cities and communities, 12: responsive consumption and production, 13: climate action.

Adaptation of buildings for climate change: A literature review

FACULTY OF ENGINEERING AND SUSTAINABLE DEVELOPMENT