Mingming Hu

Bio: Mingming Hu is an academic researcher from Leiden University. The author has contributed to research in topics: Life-cycle assessment & Material flow analysis. The author has an hindex of 17, co-authored 37 publications receiving 965 citations. Previous affiliations of Mingming Hu include Chongqing University & Huazhong University of Science and Technology.

Future material demand for automotive lithium-based batteries

Abstract: The world is shifting to electric vehicles to mitigate climate change. Here, we quantify the future demand for key battery materials, considering potential electric vehicle fleet and battery chemistry developments as well as second-use and recycling of electric vehicle batteries. We find that in a lithium nickel cobalt manganese oxide dominated battery scenario, demand is estimated to increase by factors of 18–20 for lithium, 17–19 for cobalt, 28–31 for nickel, and 15–20 for most other materials from 2020 to 2050, requiring a drastic expansion of lithium, cobalt, and nickel supply chains and likely additional resource discovery. However, uncertainties are large. Key factors are the development of the electric vehicles fleet and battery capacity requirements per vehicle. If other battery chemistries were used at large scale, e.g. lithium iron phosphate or novel lithium-sulphur or lithium-air batteries, the demand for cobalt and nickel would be substantially smaller. Closed-loop recycling plays a minor, but increasingly important role for reducing primary material demand until 2050, however, advances in recycling are necessary to economically recover battery-grade materials from end-of-life batteries. Second-use of electric vehicles batteries further delays recycling potentials.

Iron and steel in Chinese residential buildings: A dynamic analysis

Abstract: The rise of China to become world largest iron and steel producer and consumer since the late 1990s can be largely attributed to urbanization, with about 20% of China's steel output used by residential buildings, and about 50% for the construction sector as a whole. Previously, a dynamic material flow analysis (MFA) model was developed to analyze the dynamics of the rural and the urban housing systems in China. This model is expanded here to specifically analyze iron and steel demand and scrap availability from the housing sector. The evolution of China's housing stock and related steel is simulated from 1900 through 2100. For almost all scenarios, the simulation results indicate a strong drop in steel demand for new housing construction over the next decades, due to the expected lengthening of the – presently extremely short – life span of residential buildings. From an environmental as well as a resource conservation point of view, this is a reassuring conclusion. Calculations for the farther future indicate that the demand for steel will not just decrease but will rather oscillate: the longer the life spans of buildings, the stronger the oscillation. The downside of this development would be the overcapacities in steel production. A scenario with slightly lower life spans but a strong emphasis on secondary steel production might reduce the oscillation at moderate environmental costs.

Dynamic Material Flow Analysis for Strategic Construction and Demolition Waste Management in Beijing

Abstract: Summary Of all materials extracted from the earth's crust, the construction sector uses 50%, producing huge amounts of construction and demolition waste (CDW). In Beijing, presently 35 million metric tons per year (megatonnes/year [Mt/yr]) of CDW are generated. This amount is expected to grow significantly when the first round of mass buildings erected in the 1990s starts to be demolished. In this study, a dynamic material flow analysis (MFA) is conducted for Beijing's urban housing system, with the demand for the stock of housing floor area taken as the driver. The subsequent effects on construction and demolition flows of housing floor area and the concurrent consumption and waste streams of concrete are investigated for Beijing from 1949 and projected through 2050. The per capita floor area (PCFA) is a key factor shaping the material stock of housing. Observations in Beijing, the Netherlands, and Norway indicate that PCFA has a strong correlation with the local gross domestic product (GDP). The lifetime of dwellings is one of the most important variables influencing future CDW generation. Three scenarios, representing the current trend extension, high GDP growth, and lengthening the lifetime of dwellings, are analyzed. The simulation results show that CDW will rise, unavoidably. A higher growth rate of GDP and the consequent PCFA will worsen the situation in the distant future. Prolonging the lifetime of dwellings can postpone the arrival of the peak CDW. From a systematic view, recycling is highly recommended for long-term sustainable CDW management.

Dynamics of urban and rural housing stocks in China

Abstract: The massive migration flows from rural to urban areas in China, combined with an expected decline in the total population over the next decades, leads to two important challenges for China's housing: the growth of its urban housing stock and the shrinkage of rural housing. The rural and urban housing systems in China were analyzed using a dynamic material flow analysis model for the period 1900–2100 for several scenarios assuming different development paths for population, urbanization, housing demand per capita, and building lifetime. The simulation results indicate that new housing construction is likely to decline for several decades due to the fast growth over the past 30 years and the expected increased longevity of dwellings. Such an oscillation of new construction activity would have significant implications for the construction industry, employment, raw material demand, and greenhouse gas emissions to produce the construction materials. Policy and practical options for mitigating the negative impa...

Urban building energy modeling – A review of a nascent field

Abstract: Over the past decades, detailed individual building energy models (BEM) on the one side and regional and country-level building stock models on the other side have become established modes of analysis for building designers and energy policy makers, respectively. More recently, these two toolsets have begun to merge into hybrid methods that are meant to analyze the energy performance of neighborhoods, i.e. several dozens to thousands of buildings. This paper reviews emerging simulation methods and implementation workflows for such bottom-up urban building energy models (UBEM). Simulation input organization, thermal model generation and execution, as well as result validation, are discussed successively and an outlook for future developments is presented.

Environmental impacts and decarbonization strategies in the cement and concrete industries

Abstract: The use of cement and concrete, among the most widely used man-made materials, is under scrutiny. Owing to their large-scale use, production of cement and concrete results in substantial emission of greenhouse gases and places strain on the availability of natural resources, such as water. Projected urbanization over the next 50–100 years therefore indicates that the demand for cement and concrete will continue to increase, necessitating strategies to limit their environmental impact. In this Review, we shed light on the available solutions that can be implemented within the next decade and beyond to reduce greenhouse gas emissions from cement and concrete production. As the construction sector has proven to be very slow-moving and risk-averse, we focus on minor improvements that can be achieved across the value chain, such as the use of supplementary cementitious materials and optimizing the clinker content of cement. Critically, the combined effect of these marginal gains can have an important impact on reducing greenhouse gas emissions by up to 50% if all stakeholders are engaged. In doing so, we reveal credible pathways for sustainable concrete use that balance societal needs, environmental requirements and technical feasibility. Concrete is one of the most widely used man-made materials and is critical for the ongoing urbanization of the global population. However, owing to its widespread use, concrete can have a negative impact on the environment. This Review provides medium-term and long-term solutions to address the environmental concerns surrounding concrete production.

Gross domestic product.

Abstract: This news article reports on the events occurring and the views taken at the 1995 UN Conference on Women held in Beijing China and the Nongovernmental Organization (NGO) Forum. The setting in China for this decennially occurring conference was appropriate for the discussion of womens rights. Despite the selective coverage of the conference by Chinese official reports word would trickle out in whispers to Chinese women about some new ideas. Chinese visa restrictions on participants of the NGO Forum forced many women to devise ingenious ways of gaining entrance to the meetings. The alliance between the Holy See and Islam disciples threatened to undermine basic goals of conference to open up access to contraception and to change property rights. The conference chair diplomatically found justification for praise of unpopular views despite the disputes among a majority of delegates. The aim of the conference was to obtain a common understanding of some basic rights and not 100% agreement. Womens economic contributions have not been recognized in gross domestic product calculations. The World Bank has reported that about $13 billion is unaccounted for income and unwaged income of which about $8.5 billion is due to womens productivity. Women expressed the desire for recognition of their economic contribution. Since the last womens conference held in Nairobi in 1985 there has been an increase in world poverty. Uganda expends more on servicing its debt than on health and education. There was general agreement that gender equity was a goal but there was less consensus on how to achieve it.

Modeling Metal Stocks and Flows: A Review of Dynamic Material Flow Analysis Methods

Abstract: Dynamic material flow analysis (MFA) is a frequently used method to assess past, present, and future stocks and flows of metals in the anthroposphere. Over the past fifteen years, dynamic MFA has contributed to increased knowledge about the quantities, qualities, and locations of metal-containing goods. This article presents a literature review of the methodologies applied in 60 dynamic MFAs of metals. The review is based on a standardized model description format, the ODD (overview, design concepts, details) protocol. We focus on giving a comprehensive overview of modeling approaches and structure them according to essential aspects, such as their treatment of material dissipation, spatial dimension of flows, or data uncertainty. The reviewed literature features similar basic modeling principles but very diverse extrapolation methods. Basic principles include the calculation of outflows of the in-use stock based on inflow or stock data and a lifetime distribution function. For extrapolating stocks and fl...