Roland Geyer

Roland Geyer
University of California, Santa Barbara | UCSB · Bren School of Environmental Science and Management

PhD, Dipl.-Phys.

About

104
Publications
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Publications

Publications (104)
Article
Synthetic microfibers have been identified as the most prevalent type of microplastic in samples from aquatic, atmospheric, and terrestrial environments across the globe. Apparel washing has shown to be a major source of microfiber pollution. We used California as a case study to estimate the magnitude and fate of microfiber emissions, and to evalu...
Article
Recently, California has made large investments in wastewater recycling to replace applications that use potable water. It may be expected that the use of recycled water reduces potable water use, but such an equivalency is not assured. The addition of recycled water infrastructure in a large Californian water district creates a natural experiment...
Technical Report
Full-text available
Marine litter, including plastics and microplastics, is accumulating in the world’s oceans at an unprecedented rate. The volume of plastics currently in the oceans has been estimated at between 75 million and 199 million tons1. Found in sea floor sediments and on beaches, among many other locations globally, plastics are are becoming part of the Ea...
Article
Full-text available
With human food production a major driver of global environmental change, there is increasing recognition of the importance of shifting towards more sustainable dietary patterns. With wholesale dietary change notoriously difficult to implement at scale, various new food analogues have emerged to serve as qualitatively similar (e.g., taste, texture)...
Chapter
Book
The Business of Less rewrites the book on business and the environment. For the last thirty years, corporate sustainability was synonymous with the pursuit of 'eco-efficiency' and 'win-win' opportunities. The notion of 'eco-efficiency' gives us the illusion that we can achieve environmental sustainability without having to question the pursuit of n...
Article
Full-text available
Derelict fishing gear is a highly visible source of marine plastic pollution, causing mortality and ecosystem degradation with uncertain long‐term consequences. The quantity of derelict gear entering the oceans remains unknown because of heterogeneity in fishing gear and effort, as well as inadequate monitoring. Prior studies have been limited in s...
Article
Full-text available
Industrial fishing, instrumental in feeding the world's population while providing a livelihood to many people, also presents a variety of hazards to the health of the ocean, including the accumulation of derelict fishing gear. Although direct evidence of harm from derelict gear is abundant, efforts to quantify and assess the threats posed by it ar...
Article
Reversing the extraordinary growth in the production and accumulation of primary plastics in the environment will require collaboration across research disciplines and scales—from the chemical building blocks to product life cycles, producer and consumer incentives, and waste management. After a recent Cell Press LabLinks symposium on the topic, th...
Article
Full-text available
Perovskite solar cells (PSCs), one of the third-generation photovoltaic (PV) technologies, have recently become a very popular topic in photovoltaic research. This technology, which is a candidate for commercialization in the future, needs to be evaluated from an environmental point of view. The amount of electricity consumption is the most importa...
Article
Full-text available
Synthetic microfibers are found virtually everywhere in the environment, but emission pathways and quantities are poorly understood. By connecting regionalized global datasets on apparel production, use, and washing with emission and retention rates during washing, wastewater treatment, and sludge management, we estimate that 5.6 Mt of synthetic mi...
Article
Full-text available
PurposeEnvironmental assessments of electric vehicles (EV) require scientifically sound and robust fuel consumption models. The purpose of this paper is to introduce a novel method and model for calculating energy demand of battery electric (BEV) and series plug-in hybrid electric (PHEV) vehicles.Methods This paper presents an open-source simulatio...
Article
Full-text available
PurposeEnvironmental assessments of efforts to reduce vehicle fuel consumption require scientifically sound and robust fuel consumption models. The purpose of this paper is to introduce a novel method and model for calculating fuel consumption.Method This paper presents a method of powertrain modeling that is based on driving and powertrain physics...
Chapter
This book chapter provides a comprehensive account of global plastic production, use, and fate from 1950 to 2017 and thus covers all plastic humankind has ever made. It starts with a brief introduction of plastic’s origin and nomenclature, followed by a detailed global material flow analysis of the 68 years of plastic mass production, use, and end-...
Article
China used to receive more than 50% of the global post-consumer plastics export, the largest share of which was PET bottles. However, China recently banned the import of foreign wastes including waste plastics. The original intention of this ban was to protect China’s ecosystem quality and human health, while its environmental implications have yet...
Chapter
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Article
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Organo-metal lead halide perovskite solar cells (PSCs) attract attention due to low cost and high power conversion efficiency. Some weak points of this technology are short lifetime, instability and expensive metal electrode deposition. Eliminating the unstable hole transport layer (HTL) and using carbon-based materials as counter electrode would a...
Article
Full-text available
Purpose Plant-based alternatives to dairy milk have grown in popularity over the last decade. Almond milk comprises the largest share of plant-based milk in the US market and, as with so many food products, stakeholders in the supply chain are increasingly interested in understanding the environmental impacts of its production, particularly its car...
Article
Full-text available
Understanding the environmental consequences of actions is becoming increasingly important in the field of industrial ecology in general, and in life cycle assessment (LCA) more specifically. However, a consensus on how to operationalize this idea has not been reached. A variety of methods have been proposed and applied to case studies that cover v...
Chapter
Plastics, or synthetic polymers, have only been mass-produced for about 70 years, but have outgrown most man-made materials. Despite the large variety of polymers, eight of them make up 95% of all primary plastics ever made, which had exceeded nine billion metric tonnes by the end of 2017. Of the seven billion tonnes of plastic waste generated so f...
Technical Report
In collaboration with the University of California, PowWow Energy developed software that uses energy data from investor-owned utility smart electric meters to calculate water flow volumes for irrigation well pumps and booster pumps. No installation of new pump hardware is required to make these measurements. Growers are offered a software-as-a-ser...
Article
Full-text available
Global population growth and changing diets increase the importance, and challenges, of reducing the environmental impacts of food production. Farmed seafood is a relatively efficient way to produce protein and has already overtaken wild fisheries. The use of protein-rich food crops, such as soy, instead of fishmeal in aquaculture feed diverts thes...
Article
Full-text available
The substitution of aluminum for steel in vehicle body and closure components is a common strategy for reducing fuel consumption. In order to assess the greenhouse gas (GHG) consequences of this decision, the system must be examined using a life cycle approach. Furthermore, attributional life cycle assessment (ALCA) does not suffice for a number of...
Article
Full-text available
Recycling only creates environmental benefits when it displaces other material production. Without displacement it only delays rather than prevents ultimate disposal. It is therefore critically important that we improve our understanding of the causality between recycling and other material production. This research focuses on estimation of the cau...
Article
Full-text available
Proponents of material recycling typically point to two environmental benefits: disposal (landfill/incinerator) reduction and primary production displacement. However, in this paper we mathematically demonstrate that, without displacement, recycling can delay but not prevent any existing end‐of‐life material from reaching final disposal. The only w...
Article
During the last decade, photovoltaic capacity in the United States has grown annually by 65% on average. Such rapid growth in capacity is naturally followed by an equally rapid growth of PV waste generation. This paper quantifies the future PV waste from the 69.7 GW reported as major PV projects (≥1 MW) in the U.S. at the end of 2015, including not...
Article
Large growth in renewable energy technology is required to combat climate change. Photovoltaic (PV) is the most promising technology with the largest potential, and Mexico has one of the best locations to exploit solar resources. During 2015, the Mexican government approved 7.8 GW of PV projects. This PV deployment is linked to a great generation o...
Article
Full-text available
Plastics have outgrown most man-made materials and have long been under environmental scrutiny. However, robust global information, particularly about their end-of-life fate, is lacking. By identifying and synthesizing dispersed data on production, use, and end-of-life management of polymer resins, synthetic fibers, and additives, we present the fi...
Article
Full-text available
Recycling materials from end-of-life products has the potential to create environmental benefit by displacing more harmful primary material production. However, displacement is governed by market forces and is not guaranteed; if full displacement does not occur, the environmental benefits of recycling are reduced or eliminated. Therefore, quantifyi...
Article
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The so-called circular economy—the concept of closing material loops to preserve products, parts, and materials in the industrial system and extract their maximum utility—has recently started gaining momentum. The idea of substituting lower-impact secondary production for environmentally intensive primary production gives the circular economy a str...
Article
Access to a reliable source of electricity creates significant benefits for developing communities. Smaller versions of electricity grids, known as microgrids, have been developed as a solution to energy access problems. Using attributional life cycle assessment, this project evaluates the environmental and energy impacts of three photovoltiac (PV)...
Article
Full-text available
Touting products like LEDs and recycled plastic packaging as “green” is misleading, because it fails to account for their effects on markets and consumer behavior and for the resulting environmental consequences. The authors offer what they say is a better approach: measuring the overall “net green” impact of the product.
Article
This project investigates the energy-water usage efficiency of large scale civil infrastructure projects involving the artificial recharge of subsurface groundwater aquifers via the reuse of treated municipal wastewater. A modeling framework is introduced which explores the various ways in which spatially heterogeneous variables such as topography,...
Chapter
For the last 100 years, virtually every automobile was an internal combustion vehicle (ICV) powered by either gasoline or diesel and mostly made from steel. Even as the ICV was identified as a source of serious environmental impact, it continued to outcompete others, arguably more environmentally benign, transportation modes. Banning lead from gaso...
Article
Full-text available
The recycling of material resources lies at the heart of the industrial ecology (IE) metaphor. The very notion of the industrial ecosystem is motivated by the idea that we should learn from natural ecosystems how to " close the loop. " Recycling is not just central to IE, it is part of everyday life. Unfortunately, how the IE community and the publ...
Article
Extended producer responsibility (EPR) legislation in the United States, which currently only exists on the state level, now includes three mattress EPR acts, which intend to shift the financial and operational burden of mattress end-of-life (EOL) management away from local and state government. It is important to keep in mind, however, that the or...
Article
Full-text available
The most significant environmental benefit of recycling or reusing a wide range of products and materials is typically the potential to displace primary material production; lack of displacement significantly reduces the environmental benefits of these activities. Because no consensus method to estimate displacement rate has emerged, environmental...
Article
Plastic debris in the marine environment is widely documented, but the quantity of plastic entering the ocean from waste generated on land is unknown. By linking worldwide data on solid waste, population density, and economic status, we estimated the mass of land-based plastic waste entering the ocean. We calculate that 275 million metric tons (MT)...
Article
Full-text available
Used oil collection rates over the period from 2007 to 2012 were estimated from state hazardous waste hauling records.•A methodology is presented for computing an aggregate material flow measurement from a collection of observations.•Over the study period, about 375–450 kt of used oil wastes were collected each year, amounting to 70–80% of recovera...
Article
Full-text available
Purpose Geospatial details about land use are necessary to assess its potential impacts on biodiversity. Geographic information systems (GIS) are adept at modeling land use in a spatially explicit manner, while life cycle assessment (LCA) does not conventionally utilize geospatial information. This study presents a proof-of-concept approach for cou...
Article
Society faces a severe environmental challenge posed by the rapid advance of technology scaling. The high cost in manufacturing energy, materials, and disposal is worrisome with the increasing number of smartphones. To mitigate the impact of future devices, the authors propose a design for reuse model in which obsolete devices will be reused for a...
Article
Full-text available
Purpose Waste management for end-of-life (EoL) smartphones is a growing problem due to their high turnover rate and concentration of toxic chemicals. The versatility of modern smartphones presents an interesting alternative waste management strategy: repurposing. This paper investigates the environmental impact of smartphone repurposing as compared...
Article
Full-text available
Purpose Disposable beverage bottles made of polyethylene terephthalate (PET) stand in sharp contrast to many other disposable plastic packaging systems in the US for their high level of post-consumer recovery for recycling. This is due in part to container deposit programs in several US states, such as the California Redemption Value (CRV) program....
Article
Growth in biofuel production, which is meant to reduce greenhouse gas (GHG) emissions and fossil en-ergy demand, is increasingly seen as a threat to food supply and natural habitats. Using photovoltaics (PV) to directly convert solar radiation into electricity for battery electric vehicles (BEVs) is an alterna-tive to photosynthesis, which suffers...
Article
Full-text available
We present a material flow analysis (MFA) for polyethylene terephthalate (PET), a synthetic polymer, in the United States for the years 1996–2007. We model the industrial metabolism of PET as a network of flows linking stocks and processes. The most common worldwide use of PET is in textile production, but in the US it is increasingly used to make...
Article
Full-text available
The policies concerning product development and use are increasingly informed by life cycle assessment (LCA) and risk assessment (RA): LCA is often invoked to achieve "sustainability" whereas RA is used when seeking to avoid harm when dealing with toxic substances. In this Feature, Kuczenski et al. argue that green chemistry principles which encour...
Conference Paper
Full-text available
The rapid growth of information technology has led to substantial economic and societal benefits. Unfortunately, rapid improvements in technology has also led to an unsustainable "disposable" model in which devices are replaced in a matter of months. This model is especially problematic in the cell phone area, where over a billion phones are manufa...
Article
Full-text available
The dark side of Moore's Law is our society's insatiable need to constantly upgrade our computing devices. The high cost in manufacturing energy, materials and disposal is more worrisome the increasing number of smartphones. Repurposing smartphones for educational purpose is a promising idea and shown success in recent years. Our previous work has...
Article
Electrical power can be distributed in overhead or underground systems, both of which generate a variety of environmental impacts at all stages of their life cycles. While there is considerable literature discussing the trade-offs between both systems in terms of aesthetics, safety, cost, and reliability, environmental assessments are relatively ra...
Article
Full-text available
Purpose Geospatial details about land use are necessary to assess its potential impacts on biodiversity. Geographic information systems (GIS) are adept at modeling land use in a spatially explicit manner, while life cycle assessment (LCA) does not conventionally utilize geospatial information. This study presents a proof-of-concept approach for cou...
Article
The dark side of Moore's Law is our society's insatiable need to constantly upgrade our computing devices. As a result, the typical processor is only usedfor a fraction of it's expected lifetime, despite the immense cost to produce a processor. While the rapid advance of technology makes silicon obsolete in a few years, we propose that chips should...
Article
In the 1930s, chlorofluorocarbons (CFCs) were developed as safe, non-reactive alternatives to toxic and explosive refrigerants and propellants such as ammonia, chloromethane, and sulfur dioxide. American engineer Thomas Midgley famously demonstrated these properties by inhaling Freon (CFC-12) and blowing out a candle with it. He was presented with...
Article
Throughout their life cycle stages—material production, package manufacture, distribution, end-of-life management—packaging systems consume natural resources and energy, generate waste, and emit pollutants. Each of these stages also carries a financial cost. Motivated by a desire to decrease environmental burdens while reducing financial costs asso...