Energy is sustainable if it "meets the needs of the present without compromising the ability of future generations to meet their own needs." Definitions of sustainable energy usually look at its effects on the environment, the economy, and society. These impacts range from greenhouse gas emissions and air pollution to energy poverty and toxic waste. Renewable energy sources such as wind, hydro, solar, and geothermal energy can cause environmental damage, but are generally far more sustainable than fossil fuel sources.
Green building refers to both a structure and the application of processes that are environmentally responsible and resource-efficient throughout a building's life-cycle: from planning to design, construction, operation, maintenance, renovation, and demolition. This requires close cooperation of the contractor, the architects, the engineers, and the client at all project stages. The Green Building practice expands and complements the classical building design concerns of economy, utility, durability, and comfort. Green building also refers to saving resources to the maximum extent, including energy saving, land saving, water saving, material saving, etc., during the whole life cycle of the building, protecting the environment and reducing pollution, providing people with healthy, comfortable and efficient use of space, and being in harmony with nature. Buildings that live in harmony; green building technology focuses on low consumption, high efficiency, economy, environmental protection, integration and optimization.’
Energy policies are the government's strategies and decisions regarding the production, distribution, and consumption of energy within a specific jurisdiction. The energy sector emits more greenhouse gas worldwide than any other sector. Therefore, energy policies are closely related to climate change mitigation policies. These decisions affect how high the greenhouse gas emissions by that country are. The main components of energy policy include legislation, international treaties, energy subsidies and other public policy techniques.
A low-energy house is characterized by an energy-efficient design and technical features which enable it to provide high living standards and comfort with low energy consumption and carbon emissions. Traditional heating and active cooling systems are absent, or their use is secondary. Low-energy buildings may be viewed as examples of sustainable architecture. Low-energy houses often have active and passive solar building design and components, which reduce the house's energy consumption and minimally impact the resident's lifestyle. Throughout the world, companies and non-profit organizations provide guidelines and issue certifications to guarantee the energy performance of buildings and their processes and materials. Certifications include passive house, BBC—Bâtiment Basse Consommation—Effinergie (France), zero-carbon house (UK), and Minergie (Switzerland).
Passive house is a voluntary standard for energy efficiency in a building, which reduces the building's ecological footprint. Conforming to these standards results in ultra-low energy buildings that require little energy for space heating or cooling. A similar standard, MINERGIE-P, is used in Switzerland. Standards are available for residential properties and several office buildings, schools, kindergartens and a supermarket have also been constructed to the standard. The design is not an attachment or supplement to architectural design, but a design process that integrates with architectural design. Although it is generally applied to new buildings, it has also been used for refurbishments.
Climate change mitigation (or decarbonisation) is action to limit the greenhouse gases in the atmosphere that cause climate change. Climate change mitigation actions include conserving energy and replacing fossil fuels with clean energy sources. Secondary mitigation strategies include changes to land use and removing carbon dioxide (CO2) from the atmosphere. Costs of climate change mitigation are estimated at around 1% and 2% of GDP. Current climate change mitigation policies are insufficient as they would still result in global warming of about 2.7 °C by 2100, significantly above the 2015 Paris Agreement's goal of limiting global warming to below 2 °C.
A Zero-Energy Building (ZEB), also known as a Net Zero-Energy (NZE) building, is a building with net zero energy consumption, meaning the total amount of energy used by the building on an annual basis is equal to the amount of renewable energy created on the site or in other definitions by renewable energy sources offsite, using technology such as heat pumps, high efficiency windows and insulation, and solar panels.
Renewable heat is an application of renewable energy referring to the generation of heat from renewable sources; for example, feeding radiators with water warmed by focused solar radiation rather than by a fossil fuel boiler. Renewable heat technologies include renewable biofuels, solar heating, geothermal heating, heat pumps and heat exchangers. Insulation is almost always an important factor in how renewable heating is implemented.
Greenhouse gas (GHG) emissions from human activities intensify the greenhouse effect. This contributes to climate change. Carbon dioxide, from burning fossil fuels such as coal, oil, and natural gas, is one of the most important factors in causing climate change. The largest emitters are China followed by the United States. The United States has higher emissions per capita. The main producers fueling the emissions globally are large oil and gas companies. Emissions from human activities have increased atmospheric carbon dioxide by about 50% over pre-industrial levels. The growing levels of emissions have varied, but have been consistent among all greenhouse gases. Emissions in the 2010s averaged 56 billion tons a year, higher than any decade before. Total cumulative emissions from 1870 to 2022 were 703 GtC, of which 484±20 GtC from fossil fuels and industry, and 219±60 GtC from land use change. Land-use change, such as deforestation, caused about 31% of cumulative emissions over 1870–2022, coal 32%, oil 24%, and gas 10%.
The Climate Change Committee (CCC), originally named the Committee on Climate Change, is an independent non-departmental public body, formed under the Climate Change Act (2008) to advise the United Kingdom and devolved Governments and Parliaments on tackling and preparing for climate change. The Committee provides advice on setting carbon budgets, and reports regularly to the Parliaments and Assemblies on the progress made in reducing greenhouse gas emissions. Notably, in 2019 the CCC recommended the adoption of a target of net zero greenhouse gas emissions by the United Kingdom by 2050. On 27 June 2019 the British Parliament amended the Climate Change Act (2008) to include a commitment to net zero emissions by 2050. The CCC also advises and comments on the UK's progress on climate change adaptation through updates to Parliament.
The 2030 Challenge is an initiative by Edward Mazria and Architecture 2030 to make all new buildings and renovations carbon-neutral by the year 2030 to avoid the catastrophic effects of climate change caused by the building sector. Buildings, construction, and operational activities generate nearly 40% of annual Greenhouse Gas (GHG) emissions, consequently, there is a larger scope to stabilize and reverse emissions in this sector, in order to avoid increased global warming to reach a tipping point. Therefore, instead of seeing it as a trying issue, Architecture 2030, a non-profit organization, strives to beat the woes of climate change by implementing energy-efficient planning and design.
The United States produced 5.2 billion metric tons of carbon dioxide equivalent greenhouse gas (GHG) emissions in 2020, the second largest in the world after greenhouse gas emissions by China and among the countries with the highest greenhouse gas emissions per person. In 2019 China is estimated to have emitted 27% of world GHG, followed by the United States with 11%, then India with 6.6%. In total the United States has emitted a quarter of world GHG, more than any other country. Annual emissions are over 15 tons per person and, amongst the top eight emitters, is the highest country by greenhouse gas emissions per person.
The passive solar design of buildings includes consideration of their orientation to the sun and their thermal mass, factors which have been incorporated to a greater or lesser extent in vernacular architecture for thousands of years. Ancient Greeks, Romans, and Chinese were the first to refine and develop the basic principles of passive solar design, but European technological advances were largely abandoned after the Fall of Rome. It was not until the 20th century that interest in the principles of passive solar design had a resurgence in Europe and the U.S.A., with architects such as George F. Keck and Frank Lloyd Wright. In the 21st century, worldwide endeavours to reduce power consumption have kept the interest in passive solar technology alive.
Greenhouse gas emissions by Australia totalled 533 million tonnes CO2-equivalent based on greenhouse gas national inventory report data for 2019; representing per capita CO2e emissions of 21 tons, three times the global average. Coal was responsible for 30% of emissions. The national Greenhouse Gas Inventory estimates for the year to March 2021 were 494.2 million tonnes, which is 27.8 million tonnes, or 5.3%, lower than the previous year. It is 20.8% lower than in 2005. According to the government, the result reflects the decrease in transport emissions due to COVID-19 pandemic restrictions, reduced fugitive emissions, and reductions in emissions from electricity; however, there were increased greenhouse gas emissions from the land and agriculture sectors.
Mark Zachary Jacobson is a professor of civil and environmental engineering at Stanford University and director of its Atmosphere/Energy Program. He is also a co-founder of the non-profit, Solutions Project.
A zero-carbon city is a goal of city planners that can be variously defined. In a narrower sense of energy production and use, a zero-carbon city is one that generates as much or more carbon-free sustainable energy as it uses. In a broader sense of managing greenhouse gas emissions, a zero-carbon city is one that reduces its carbon footprint to a minimum by using renewable energy sources; reducing all types of carbon emissions through efficient urban design, technology use and lifestyle changes; and balancing any remaining emissions through carbon sequestration. Since the supply chains of a city stretch far beyond its borders, Princeton University's High Meadows Environmental Institute suggests using a transboundary definition of a net-zero carbon city as "one that has net-zero carbon infrastructure and food provisioning systems".
In 2021, net greenhouse gas (GHG) emissions in the United Kingdom (UK) were 427 million tonnes (Mt) carbon dioxide equivalent, 80% of which was carbon dioxide itself. Emissions increased by 5% in 2021 with the easing of COVID-19 restrictions, primarily due to the extra road transport. The UK has over time emitted about 3% of the world total human caused CO2, with a current rate under 1%, although the population is less than 1%.
Renewables supply a quarter of energy in Turkey, including heat and electricity. Some houses have rooftop solar water heating, and hot water from underground warms many spas and greenhouses. In parts of the west hot rocks are shallow enough to generate electricity as well as heat. Wind turbines, also mainly near western cities and industry, generate a tenth of Turkey’s electricity. Hydropower, mostly from dams in the east, is the only modern renewable energy which is fully exploited. Hydropower averages about a fifth of the country's electricity, but much less in drought years. Apart from wind and hydro, other renewables; such as geothermal, solar and biogas; together generated almost a tenth of Turkey’s electricity in 2022. Türkiye has ranked 5th in Europe and 12th in the world in terms of installed capacity in renewable energy. The share of renewables in Türkiye’s installed power reached to 54% at the end of 2022.
India is ranked seventh among the list of countries most affected by climate change in 2019. India emits about 3 gigatonnes (Gt) CO2eq of greenhouse gases each year; about two and a half tons per person, which is less than the world average. The country emits 7% of global emissions, despite having 17% of the world population. Temperature rises on the Tibetan Plateau are causing Himalayan glaciers to retreat, threatening the flow rate of the Ganges, Brahmaputra, Yamuna and other major rivers. A 2007 World Wide Fund for Nature (WWF) report states that the Indus River may run dry for the same reason. Heat waves' frequency and intensity are increasing in India because of climate change. Severe landslides and floods are projected to become increasingly common in such states as Assam. The climate change performance index of India ranks eighth among 63 countries which account for 92% of all GHG emissions in the year 2021.
China's greenhouse gas emissions are the largest of any country in the world both in production and consumption terms, and stem mainly from coal burning, including coal power, coal mining, and blast furnaces producing iron and steel. When measuring production-based emissions, China emitted over 14 gigatonnes (Gt) CO2eq of greenhouse gases in 2019, 27% of the world total. When measuring in consumption-based terms, which adds emissions associated with imported goods and extracts those associated with exported goods, China accounts for 13 gigatonnes (Gt) or 25% of global emissions. According to the Carbon Majors Database, Chinese state coal production alone accounts for 14% of historic global emissions.
