Life cycle assessment of white roof and sedum-tray garden roof for office buildings in China

White roof (WR) and Sedum lineare tray garden roof (STGR) have been convinced to improve the energy-efficiency and provide various benefits for conventional impervious grey roofs. Some national and local standards have standardized and recommended these technologies in existing building retrofits, however, they do not include assessment and choice of a particular roof retrofit in different climates. This paper presents a 40-year life-cycle cost analysis (LCCA) of an office building roof retrofitted by adding either WR or STGR over an existing grey roof in five cities, located in four Chinese climate zones. The LCCA find that the WR retrofits exhibit positive life-cycle net savings (NS) in warm winter zones, ranging 5.7–35.1 CNY/m 2 , and STGR retrofits have negative NS of -81.3– -16.7 CNY/m 2 in all climate zones. The NS of both WR and STGR generally tend to improve as one moves from the coldest cities to the warmest cities. LCCA results suggest that adding new building codes concerning crediting or prescribing WR and STGR retrofits into office buildings with grey roofs in hot summer climate zones and warm winter zone in China, respectively. And featured by more specific requirements, the localized Technical Norms help promote the implementation of new building codes

Lessons from submission and approval process of large-scale energy efficiency CDM methodologies

The Clean Development Mechanism (CDM) so far has failed to mobilize a substantial amount of energy efficiency projects; less than 4% of credits come from this category. This is due to the fact that only few methodologies for setting of baselines and monitoring project emissions have been approved by the CDM Executive Board (EB). While energy efficiency methodologies have the highest share of methodology submissions, they also suffer from the highest rejection rate. Just 25% of energy efficiency methodology submissions have been approved or consolidated. The applicability of those methodologies is typically narrow and the requirements for monitoring are heavy. Industrial efficiency improvements (e.g. waste heat recovery) are covered relatively well, whereas there are glaring gaps with regards to electricity generation and transmission as well as transport. Demand-side management in households and commercial buildings so far has not been covered either. The EB has not been willing to accept empirical models and performance benchmarks as a basis for baseline emission determination. We see some inconsistencies in decision-making of the Methodology Panel (MP)/ EB particularly with respect to the underlying baseline approach, treatment of rebound effects and endogenous energy efficiency improvement, and additionality assessment of programmatic CDM. A key challenge for energy efficiency projects is determination of additionality; attempts to focus on the barrier analysis only have been rejected by the MP/ EB. A new challenge comes up in the context of programmatic CDM which could give a boost to demand-side activities if the rules are less cumbersome than those for single projects. Here, the application of the additionality test again becomes crucial. --Clean Development Mechanism,Energy efficiency improvement,Baseline and monitoring methodology,Additionality

Methodologies for Assessment of Building's Energy Efficiency and Conservation: A Policy-Maker View

Recent global peer-review reports have concluded on importance of buildings in tacking the energy security and climate change challenges. To integrate the buildings energy efficiency into the policy agenda, significant research efforts have been recently done. More specifically, the public domain provides a bulk of literature on the application of buildings-related efficiency technologies and behavioural patterns, barriers to penetration of these practices, policies to overcome these barriers. From the policy-making perspective it is useful to understand how far our understanding of building energy efficiency goes and the approaches and methodologies are behind such assessment.Buildings, energy efficiency potential, greenhouse gas mitigation, policy assessment, energy policy impact evaluation, sectoral efficiency targets

Building stock dynamics and its impacts on materials and energy demand in China

China hosts a large amount of building stocks, which is nearly 50 billion square meters. Moreover, annual new construction is growing fast, representing half of the world's total. The trend is expected to continue through the year 2050. Impressive demand for new residential and commercial construction, relative shorter average building lifetime, and higher material intensities have driven massive domestic production of energy intensive building materials such as cement and steel. This paper developed a bottom-up building stock turnover model to project the growths, retrofits and retirements of China's residential and commercial building floor space from 2010 to 2050. It also applied typical material intensities and energy intensities to estimate building materials demand and energy consumed to produce these building materials. By conducting scenario analyses of building lifetime, it identified significant potentials of building materials and energy demand conservation. This study underscored the importance of addressing building material efficiency, improving building lifetime and quality, and promoting compact urban development to reduce energy and environment consequences in China

Supportive governance for city-scale low carbon building retrofits: a case study from Shanghai

There is significant potential for reducing energy use and emissions from buildings through energy efficiency retrofits. However, a number of barriers, including long payback periods and uncertainties around business models and technologies, restrict large scale implementation. A recent joint project, piloting green energy schemes and low-carbon investments in public and commercial buildings in the Changning district of Shanghai, China, indicated opportunities to break through these barriers. This study conducted a cost benefit analysis to investigate how an innovative combination of financial and non-financial supported retrofits, and could serve as a model for other urban areas. In total, 44 retrofit sub-projects were carried out and achieved energy savings of 30,217 tons of coal equivalent. The average payback period was 2.43 years, and with subsidies was further reduced to 1.79 years. The Changning Low Carbon Office played a critical role in coordinating and supporting the uptake of retrofit measures but non-economic factors continue to restrict investment by financial institutions and the implementation of retrofits on a larger scale

Assessing the Feasibility of Nutrient Trading Between Point Sources and Nonpoint Sources in the Chao Lake Basin Final

This pilot project will determine the Feasibility of an effective point-nonpoint source nutrient trading program could be established in the Lake Chao Basin, Program's potential benefits, Framework and necessary elements for such a program

Low-Carbon City Policy Databook: 72 Policy Recommendations for Chinese Cities from the Benchmarking and Energy Savings Tool for Low Carbon Cities

This report is designed to help city authorities evaluate and prioritize more than 70 different policy strategies that can reduce their city’s energy use and carbon-based greenhouse gas emissions of carbon dioxide (CO2) and methane (CH4). Local government officials, researchers, and planners can utilize the report to identify policies most relevant to local circumstances and to develop a low carbon city action plan that can be implemented in phases, over a multi-year timeframe. The policies cover nine city sectors: industry, public and commercial buildings, residential buildings, transportation, power and heat, street lighting, water & wastewater, solid waste, and urban green space. See Table 1 for a listing of the policies. Recognizing the prominence of urban industry in the energy and carbon inventories of Chinese cities, this report includes low carbon city policies for the industrial sector. The policies gathered here have proven effective in multiple locations around the world and have the potential to achieve future energy and carbon savings in Chinese cities

A roadmap for China to peak carbon dioxide emissions and achieve a 20% share of non-fossil fuels in primary energy by 2030

As part of its Paris Agreement commitment, China pledged to peak carbon dioxide (CO2) emissions around 2030, striving to peak earlier, and to increase the non-fossil share of primary energy to 20% by 2030. Yet by the end of 2017, China emitted 28% of the world's energy-related CO2 emissions, 76% of which were from coal use. How China can reinvent its energy economy cost-effectively while still achieving its commitments was the focus of a three-year joint research project completed in September 2016. Overall, this analysis found that if China follows a pathway in which it aggressively adopts all cost-effective energy efficiency and CO2 emission reduction technologies while also aggressively moving away from fossil fuels to renewable and other non-fossil resources, it is possible to not only meet its Paris Agreement Nationally Determined Contribution (NDC) commitments, but also to reduce its 2050 CO2 emissions to a level that is 42% below the country's 2010 CO2 emissions. While numerous barriers exist that will need to be addressed through effective policies and programs in order to realize these potential energy use and emissions reductions, there are also significant local environmental (e.g., air quality), national and global environmental (e.g., mitigation of climate change), human health, and other unquantified benefits that will be realized if this pathway is pursued in China