Pages (8 results)
TopGive to ERG
Your donation to ERG provides critical funding and academic opportunities for our graduate students. ERG has a 50-year history of outstanding research, teaching, policy advice and scholar-activism. ERG has researched ... Continue Reading »
Publications
“Biodiversity Scales from Plots to Biomes With a Universal Species-Area Curve” John Harte, Adam B. Smith, and David Storch“Carbon Cycle Uncertainty Increases Climate Change Risks and Mitigation Challenges” Paul A. ... Continue Reading »
Faculty by Primary Interest
Areas of Interest Climate ChangeEcologyEnergyGovernanceWaterInternational Climate Change ERG CORE David Anthoff David Anthoff is an environmental economist who studies climate change and environmental policy. He co-develops the integrated assessment model ... Continue Reading »
Affiliated Faculty
ERG has a small core faculty but a much larger group of affiliated faculty. Affiliated faculty are based in other departments on campus or at the Lawrence Berkeley National Laboratory, ... Continue Reading »
Who We Are
A Brief History of ERG For thirty years, the Energy and Resources Group (ERG) at the University of California, Berkeley has provided its outstanding graduate students and exceptional faculty the ... Continue Reading »
Summer Instructors
The Energy and Resources Group summer instructors understand the complex and interdisciplinary nature of sustainability. All have significant experience teaching and/or professional experience in the subject areas of their courses. ... Continue Reading »
Minor/Certificate in Sustainability — Courses
Summer 2022 Curriculum ERG’s minor and certificate require a minimum of five courses and 15 total units of coursework, completed over one or two summers (or for a UC Berkeley ... Continue Reading »
Awards
Student Awards ERG students have been recognized nationally and internationally for their research. Below, you can find a selection of recent awards received by ERG Masters and PhD students. CAL ... Continue Reading »
Faculty (5 results)
TopMeg Mills-Novoa
Assistant Professor
Meg Mills-Novoa is a human-environment geographer who researches the enduring impacts of climate change adaptation projects. She is jointly appointed to the Energy and Resources Group and the Department of Environmental Science, Policy, and Management.
- climate change adaptation
- critical development studies
- Deforestation
- Latin America
- participatory mixed methods
- political ecology of global change
- water justice
Andrew D. Jones
Assistant Adjunct Professor
Dr. Jones is an Earth scientist who works at the interface of human and environmental systems. His research uses quantitative models and data analysis to understand climate change and human-Earth system interactions at decision-relevant scales. He also collaborates with social scientists and interacts closely with stakeholders to understand how science can effectively provide actionable insight into strategies for increasing resilience of energy water, food, and urban systems.
Margaret Torn
Adjunct Professor
The focus of my work is carbon and nutrient cycling in terrestrial ecosystems and trace-gas flux between soil and atmosphere. I conduct research on soil carbon, global change, and the impacts of human activities on ecosystem processes.
John Harte
Professor of the Graduate School
John Harte is a physicist turned ecologist. His research interests span ecological field research, the theory of complex systems, and policy analysis. Current interests include applying insights from information theory to the analysis of complex ecosystems and empirical investigation of climate-ecosystem feedback dynamics.
David Anthoff
Associate Professor
David Anthoff is an environmental economist who studies climate change and environmental policy. He co-develops the integrated assessment model FUND that is used widely in academic research and in policy analysis.
Students (9 results)
TopDennis Best
MS, PhD
Dennis has focused his career on technology and sustainability policy in emerging and developing economies. His research interests include technology and innovation policy and impacts to resource and rural development, ... Continue Reading »
- Agriculture
- China
- climate
- economics
- energy
- energy policy
- environmental markets and design
- geospatial analysis
- industrial ecology
- Innovation systems
- rural development
- South East Asia and Latin America
- technology policy
Sasha Figel
MS
Sasha is a first-year Master’s student interested in land and resource management. Her research is focused on how various groups value natural resources, how the value can be quantified, and ... Continue Reading »
Catherine Van Dyke
MA
Catherine is a second year Master’s student at ERG studying California agriculture and climate change. Her research focuses on water governance, resource allocation, and equity for farmers and ranchers in ... Continue Reading »
Jess Kersey
MS, PhD
Jess Kersey is a fourth-year PhD student broadly interested in technology, regulation, and policy to improve energy access and climate adaptation efforts across multiple geographies including East Africa, Latin America, ... Continue Reading »
Micah Elias
MS, PhD
Payment for Watershed Ecosystem Services: Effectiveness, Efficiency, and Equity (MS ’20) Micah Elias earned his B.S. in International Agricultural Development from UC Davis in 2012. After graduating he worked with ... Continue Reading »
Jesse Griffin-Carney
MS, PhD
Integrating Fuel-Based End Uses Into a Clean Electric System: Quantifying the Trade Off Between Electrification and Electrically Synthesized Fuels (MS ’20) Jess Carney is interested in understanding how sustainable energy ... Continue Reading »
Jesse Strecker
MA, MPP
Evaluating the Role of Labor Unions in the Politics of Decarbonization: Insights from Political Economy and Socio-Technical Transition Studies (MA ’19) Jesse is a student in the concurrent Master’s degree ... Continue Reading »
- climate
- democracy
- development
- ecological economics
- ecology
- economics
- energy
- environmental justice
- governance
- Heterodox Economics
Jack Chang
MA, MPP
Hydrogen’s Potential Role is California’s Zero Emissions Future (MA ’20) I have been focusing on building decarbonization policy, renewable hydrogen and and island electrification as part of my master’s degrees ... Continue Reading »
Lisa Rennels
MS, PhD
Sobol Sensitivity Analysis for Integrated Assessment Models: Supporting Result Characterization (MS ’19) Lisa is interested in using computer science to explore issues related to the economic impacts of climate change, ... Continue Reading »
Alumni (36 results)
TopMichelle Sims
MS
At ERG, Michelle is interested in environmental and equity challenges within global food systems. In particular, her research focuses on the dynamics of land use change in agricultural landscapes in ... Continue Reading »
Scott Zimmermann
MS
Sustainable Biofuels: Designing Indirect Land Use Change Regulations that are Compatible with International Trade Law (MS ’08)
Jim Williams
MS, PhD
M.S. 1986 – A Vehicular Power Plant Application of the Monolithic Solid Oxide Fuel Cell Ph.D. 1995 – Fan-Lizhi’s Big Bang: Science and Politics in Mao’s China ERG alumnus Jim Williams, now ... Continue Reading »
- acid rain
- Arctic haze
- China
- comparative religion
- cosmology
- dissidents and outlaws
- economic globalization and cultural survival
- fuel-cell powered vehicles
- global change
- over the last ten years: speech synthesizers
- science and politics
- the theory and practice of Utopia
Anne Short
MS, PhD
Understanding Urban Food Access (’05 MS) Governing Change: An Institutional Geography of Rural Land Use, Environmental Management, and Change in the North Coastal Basin of California (’10 PhD)
- environmental governanace
- land management and conservation planning
- rural land use change
- science and policy
- water quality
Michael Kiparsky
MS, PhD
Science-Policy Interface in the Case of Climate Change and California Water Management (MS ’04) A Risk Analysis for Water Resources Under Climate Change, Population Growth and Land Use Change (PhD, ... Continue Reading »
- climate adaptation in water resources management
- governance and management of complex systems
- risk and decision making in water resources
- science/policy interface
Andrew Jones
MS, PhD
Biofuel Boundaries: Estimating the Medium-Term Supply Potential of Domestic Biofuels (MS ’07) Land use change is a critical influence on the climate effects of climate policies (PhD ’12)
- Agroecology
- biogeochemistry
- climate policy
- market-based policy
- mathematical models
- social and ecological impacts of biofuels including food security/energy security/climate/land use issues
- transportation
Tim Hargrave
MA
The Impact of a Federal Grazing Fee Increase on Land Use in El Dorado County, California (’93 M.A.)
- impact of organizational culture on adoption of these beliefs and practices
- inter-organizational diffusion of new environmental beliefs and practices
Grace Wu
MS, PhD
Land Use in Renewable Energy Planning (PhD ’18) Inspired by the possibility of ecologically-bounded growth, Grace is interested in water and land use impacts of energy technologies; water management that ... Continue Reading »
- ecological economics
- GIS
- land use impacts of energy systems
- renewable resource assessment
- spatial statistics
- water-energy nexus
Morgan Levy
MS, PhD
Morgan’s research focuses on hydrology and water resources, the effects of land use and climate change on human health and the environment, human-environmental system dynamics, and environmental data science. Her ... Continue Reading »
- Agriculture
- climate
- climate change
- climate change adaptation
- eco-hydrology
- environmental data science
- environmental health science
- geographic information systems
- hydroclimatology
- hydrology
- irrigation
- water
- water resources management
Zubair Dar
MA
Zubair is a Master’s student who researches water policy and management of international river basins, and is particularly focused on hydro-politics of the Indus basin. He has researched the relationship ... Continue Reading »
- Energy Efficiency
- Hydroelectric Power Projects
- International Conflicts
- River Basin Management
- sustainability
- Water and Renewable Energy
- Water Resource Management
Karina French
MA
Karina is focused on urban climate resilience, specifically studying how climate impacts will affect social infrastructure systems that protect vulnerable populations in cities. At ERG, she is interested in the ... Continue Reading »
Alana Siegner
MA, PhD
Alana Siegner received her B.A. from Tufts University in Environmental Science and International Relations, and served as an AmeriCorps National Teaching Fellow in Boston for two years after graduating from ... Continue Reading »
- climate change education
- environmental education
- Food Justice
- Sustainable food systems
- urban agroecology
Christian Miller
MPP, MS
Measuring California’s Energy Service Affordability (MS ’19) Christian is fascinated by energy end-uses’ effect on communities’ economic and political well-being. While his formal scientific background is in biorenewable resources, his ... Continue Reading »
- climate
- development
- economics
- energy
- energy policy
- equitable energy access
- rural electrification
- transportation
Alex Dolginow
MA, MS
Valuing Co-benefits of California’s Climate Policy: Industrial Facilities and Public Health (MA ’18) Alex Dolginow is a Master’s degree candidate interested in understanding appropriate design and conditions for ‘environmental markets,’ ... Continue Reading »
Emma Tome
MS
Who Governs a Sustainable Neighborhood? Planning a Community-scale Retrofit in Oakland, California (MS ’18) Emma’s interests are at the intersection of climate change adaptation, environmental justice, and science and technology ... Continue Reading »
Adam Hanbury-Brown
MS, PhD
Predicting the future of forests under global change: the critical role of the regeneration process (PhD ’22) Adam is a PhD focused on ecosystem modeling and remote sensing. His research ... Continue Reading »
- Agriculture
- climate
- Earth System Models
- ecology
- Forest Regeneration
- Movement Ecology
- remote sensing
- Vegetation Dynamics
- Wildlife Ecology
Zeke Hausfather
PhD
Understanding and Reconciling Global Temperature Records (PhD ’19) Zeke is an energy systems analyst and data scientist with a strong interest in climate science and policy. He is currently the ... Continue Reading »
Anna Brockway
MS, PhD
New challenges facing electric power systems: Integrating technical realities and policy goals (PhD ’22) Anna Brockway is a PhD from the Energy and Resources Group at UC Berkeley. She holds ... Continue Reading »
- climate adaptation
- economics
- electricity grid
- electricity markets
- energy
- Energy System Modeling
- renewable energy integration
- renewable energy policy
- solar energy
- utility business models
Richard Barnes
PhD
Algorithms for, and Applications of, Global Terrain Analysis (PhD ’20) Richard applies computational and mathematical techniques to better understand the complex interface of society and the environment. His work includes ... Continue Reading »
Adrienne Marshall
MS
Adrienne works on climate change adaptation and mitigation in the public and private forests and wild lands of California. She is interested in understanding how the natural resources in these ... Continue Reading »
- California ecosystems
- climate change
- climate change adaptation
- ecology
- Harte Lab
- land use politics
- riparian and aquatic ecosystems
- water
Alana Siegner
MA, PhD
Growing Environmental Literacy: On Small-Scale Farms, in the Urban Agroecosystem, and in School Garden Classrooms (PhD ’20) Alana Siegner graduated from Tufts University in 2012 with a double major in ... Continue Reading »
Marcus Moench
MS, PhD
Resource Utilization and Degradation: An Integrated Analysis of Biomass Utilization Patterns in a Garhwal Hill Village, Northern Uttar Pradesh, India (’85 MS) From Forest to Agroforest: Land-Use Dynamics and Crop ... Continue Reading »
Philippe Martin
MS, PhD
Qualitative Analysis: The Method and Its Use in Modeling the Influence of Space on Ecosystems (’86 M.S.) Forest Succession and Climate Change: Coupling Land-Surface Processes and Ecological Dynamics (’90 Ph.D.)
- atmosphere/biosphere interactions
- carbon cycling
- climate change and public health - especially malaria
- energy and resources geopolitics
- integrated environmental assessment
- terrestrial biosphere modeling
Amber Kerr
PhD
Drought resilience of maize-legume agroforestry systems in Malawi (PhD ’12) Amber Kerr is an agricultural ecologist focusing on climate change impacts and adaptation. She has studied nutrient cycling in California ... Continue Reading »
Donna Green
MA, PhD
Renewable Energy Technology Systems for Remote Area Electrification in Indonesia: A Critical Review of Technology Transfer (’00 M.A.) Power Games: The Political Use of Solar Technology in Northern Thailand (04 PhD)
- climate change and equity concerns
- gender and technology issues
- globalization
- regional hierarchies and power structures
- renewable energy technology transfer especially of photovoltaic systems in Thailand
- sustainable energy use - focused in rural areas of Southeast Asia
Joachim Seel
MPP, MS, PhD
Landing on the Sun! How to Make Residential PV Price-Competitive in the U.S. with Lessons Learned in Germany (MS/MPP ’12) Socio-Economic and Engineering Assessments of Renewable Energy cost Reduction Potential (PhD ... Continue Reading »
- electricity market design
- market integration of intermittent renewable electricity
- Renewable energy markets and policy
- technology learning
Erica Newman
MS, PhD
Erica’s niche is fire, particularly in the ecologically sensitive region of French Polynesia. She has already been trained as a physicist, but her curiosity draws her to ecology. ERG has become a unique place for Erica to explore her aspirations in the biological sciences alongside those who have successfully trekked through similar transitions. Read in her own words how Erica has fine-tuned her fascinations while at ERG.
- anthropogenic impacts on fire regimes
- California chaparral
- climate change and biodiversity interactions
- Fire ecology and natural disturbance
- French Polynesia cloud forests and wet montane forests
- macroecology
Rebekah Shirley
MS, PhD
Rebekah Shirley believes that there is more than one path to a bright, energy secure future. Developing nations strive to connect more and more of their communities to energy. Many have emulated the fossil fuel intensive model of developed nations, but Rebekah believes that this is not necessarily the only way.
Autumn Preskill
MS, PhD
Autumn Petros-Good received her B.S. in Engineering from Harvey Mudd College in 2009, and her M.S. from ERG in 2011 and her PhD from ERG in 2015. She worked on ... Continue Reading »
- energy distribution & management policy
- mathematical programming approaches to energy problems
- Renewable energy usage
Benjamin Mandel
MPP, MS
Minding Electron Leakage: How Utility Regulation Can Improve Upstream Energy Efficiency (MS ’14) Ben is a concurrent MS-MPP degree student in ERG and the Goldman School of Public Policy. His ... Continue Reading »
Christopher Jones
MS, PhD
Chris Jones is Director of the CoolClimate Network, a university-government-industry partnership at the University of California, Berkeley, and Lecturer at the Haas School of Business. His primary research interests are ... Continue Reading »
- behavioral psychology
- Carbon footprint analysis
- economics
- energy
- Environmental / Climate Equity
- Environmental Policy
- Environmental Psychology
- RAEL
- transportation
- urban planning
Julian Fulton
PhD
Julian’s interests lie in the relationships between water use and economic development, focusing on modeling and governance. Mr. Fulton’s previous research includes water use in the transportation sector, conservation strategies ... Continue Reading »
- California
- cotton
- Delta
- environmental history
- footprint
- water management
- water systems
- water use
- water-energy-food nexus
Michael Cohen
MS, PhD
Michael Cohen puts the power and complexity of the grid into students' hands via a video game. We asked Michael about his innovative project and his unique experience at ERG. "In addition to developing the game itself, I am working with teachers at local high schools to develop curriculum around it and try it out with their students this year. I hope to not only create a solid educational product but also gain some insights into how technology can be used to support learning about complex systems in general."
- EMAC
- energy
- Energy System Modeling
- Integration of renewable electricity into power systems
- Video Gaming for Education
Danielle Svehla Christianson
MS, PhD
At times the problem of understanding phenomena is one of seeing. That is why Danielle explores new ways of demystifying complexity through visual representation. She seeks new techniques to illustrate often-forgotten, yet fundamental dependencies between human society and the natural world. One such technique is terrestrial laser scanning (also known as LIDAR), which she used to create a 3-D model of her ecological study site in the Sierra Nevada. This along with her seedling research seeks to inform the uncertain future of resource management.
Zoë Chafe
MPH, MS, PhD
Dr. Chafe works at the intersections of public health, air pollution, climate change, and energy use. She holds a PhD from the Energy and Resources Group (ERG), as well as ... Continue Reading »
- climate
- climate change and public health
- co-benefits (ancillary benefits) of climate change mitigation
- development
- energy
- energy transitions and impacts on air pollution
- heating and cooking with solid fuels
- household energy policy options
- Household energy use trends
- short-lived greenhouse pollutants
Nkiruka Avila
MS, PhD
Designing and Adapting Appropriate Socio-Technical Systems for the Renewable Energy Transition (PhD ’18) Nkiruka has expertise in solar grid integration and climate policy in California, and in electricity access in ... Continue Reading »
News (22 results)
TopEmission-Free Neighborhoods? The Oakland EcoBlock Project Pioneers Residential Sustainability
February 14, 2018
The College of Environmental Design (CED) at UC Berkeley spotlighted the innovative Oakland EcoBlock project this week, lead by CED professor Harrison Fraker and ERG chair Dan Kammen. The project, ... Continue Reading »
Kammen on Utah Governor Signing Bill to Advance Oakland Coal Plan
March 29, 2016
ERG professor Dan Kammen discusses the new construction of an Oakland cargo terminal that could be used to export Utah coal with KQED News.
ERG PhD Student Grace Wu Receives the 2018 Smith Conservation Research Fellowship
January 24, 2018
The David H. Smith Conservation Research Fellowship is a renowned postdoctoral program designed to support early-career scientists tackling the world’s most pressing conservation challenges. Throughout their research, the fellows partner ... Continue Reading »
ERG’s Chelsi Sparti Recipient of the 2022 Switzer Environmental Fellowship
July 29, 2022
ERG Master’s student Chelsi Sparti has recently been chosen as one of the recipients of the 2022 Switzer Environmental Fellowship, a program of the Robert and Patricia Switzer Foundation that ... Continue Reading »
ERG Professor Margaret Torn on the Growing Impact of Californian Wildfires
November 3, 2020
In the recent Scientific American article "California’s Mega Fires Have Arrived 30 Years Early", ERG adjunct professor Margaret Torn argued that as more people living in wildland-adjacent areas, the catastrophic impacts of wildfires only continues to grow. “We’re changing how catastrophic a fire is because we have put more properties and lives at risk... because we’re building in fire zones,” Torn stated.
ERG PhD Student Esther Shears on Improving Data Access and Equality
September 10, 2020
ERG PhD student Esther Shears recently published her work in the Proceedings of the National Academy of Sciences (PNAS). Her publication, titled "Improving data access democratizes and diversifies science", focuses on how critical data access is for empirical research and the diversity of scientific research. Shears shares a two-sentence summary from the abstract of what she found from her analysis, stating that "Scientists who start using Landsat data after access is improved tend to focus on previously understudied regions close to their home location and introduce novel research topics. These findings suggest that policies that improve access to valuable scientific data may promote scientific progress, reduce inequality among scientists, and increase the diversity of scientific research."
ERG Alum Patrick Gonzalez Testifies Before Congress as Expert Witness
February 21, 2019
During a recent House Natural Resources Committee event titled “Climate Change and Public Lands: Examining Impacts and Considering Adaptation Opportunities,” ERG alumnus Patrick Gonzalez (PhD ’97) provided testimony as an ... Continue Reading »
NPR Interviews Dan Kammen On U.N. Climate Convention
January 2, 2019
NPR’s Michel Martin interviewed ERG Professor Dan Kammen on the U.N. climate talks December, 2018 in Poland. “Unfortunately, because the U.S. backed out, that’s left a number of holes. Essentially, ... Continue Reading »
Faculty and Alumni Encourage You to Vote! ERG Students
October 10, 2018
As the November 6, 2018 midterm elections approach, the Energy and Resources Group faculty, students, and alumni are taking action to increase voter participation. We encourage all voices to be heard ... Continue Reading »
ERG’s EcoBlock Project Selected by Scientific American as a World Changing Idea for 2017
November 28, 2017
The Oakland EcoBlock Project is an urban sustainability experiment that focuses on reducing the footprint of a typical neighborhood block. As a mini-grid system for shared energy and water in ... Continue Reading »
New ERG Chair Daniel M. Kammen
July 25, 2017
We are pleased to announce the appointment of the new Energy and Resources Group Chair, Professor Daniel M. Kammen. His appointment began July 1, 2017. Daniel Kammen is a Professor of Energy with ... Continue Reading »
New Study by ERG Postdoc James Rising Finds Northern States Might Profit as the Planet Warms
July 6, 2017
If you live in the South, climate change could kill your economy.
Sustainable Design of Communities: Kammen and Fraker in Scientific American
July 5, 2017
Neighborhood efforts to reduce fossil fuel and water consumption, as well as greenhouse gas emissions, could go beyond serving as a model for sustainability by providing local construction jobs and revitalizing entire communities.
ERG Graduate Students Deshmukh and Wu: Can Wind and Solar Fuel Africa’s Future?
November 4, 2016
ERG Graduate Students Ranjit Deshmukh and Grace Wu's research on renewable energy in Africa was highlighted in a news article in Nature.
ERG Alumna: Disrupting the Social-Change Industry Scholz
October 26, 2016
Alumna Astrid Scholz (PhD 2001, Energy and Resources Group) seeks to disrupt the social-change industry with Sphaera Solutions.
ERG at the Paris Climate Talks
December 1, 2015
The 2015 United Nations Climate Change Conference in Paris has begun and will continue until December 11th. Energy and Resources Group faculty, students and alumni will be playing an active role at the conference and the many peripheral activities.
Holdren: What Works at ERG Works
April 13, 2015
John Holdren's "tricks of the trade" presentation plus photos during the ERG Big Event.
BOOK: Applying Anthropology and Physics to Sustainability
March 30, 2015
New book by Dove and Kammen released this week.
California could power itself three to five times over with solar
March 17, 2015
ERG postdoctoral fellow Hernandez with Hoffacker and Field from Stanford publish in Nature Climate Change.
Zoë Chafe leads new WHO Report
March 12, 2015
"We wanted to help policymakers and members of the general public understand that household heating with biomass is a complicated issue," says ERG PhD candidate Zoë Chafe.
Profs. Leach & Ray Launch UN Gender Equality Report
October 24, 2014
Dr. Isha Ray at UN Headquarters discussing report on gender equality.
ERG Alum Greacen’s book on small power
January 18, 2014
From the bottom up : how small power producers and mini-grids can deliver electrification and renewable energy in Africa
Topics (4 results)
TopNikhil Vijaykar
MS
Consolidation as a Solution for Central Valley Water Woes: An Exploratory Study in Tulare County (’13 MS)
- distributed energy in rural and urban settings
- environmental justice
- land use
- movement building and legal interventions
Margaret Torn
MS, PhD
The Threats to Biological Diversity in California (’90 MS) Environmental Controls Over Methane Flux from Ecosystems and the Potential for Feedbacks with Climatic Change (’94 PhD) See Faculty Profile
- biodiversity
- biogeochemistry
- Carbon cycle
- climate change
- conservation
- democracy
- ecosystem goods and services
- ecosystem processes
- isotopes
- land use
Derek Lemoine
MS, PhD
Greenhouse Gas Property – Introducing an Adaptable Climate Policy for an Uncertain World (MS ’07) Characterizing & Responding to Uncertainty in Climate Change (PhD ’11)
- economics
- energy markets
- energy networks
- GIS
- land use
- novel policy responses to climate change
- option value
- policy
- renewables
- uncertainty
Nancy Kiang
MS
The Urban Landscape and Personal Travel Behavior: Logit Analysis of Spatial Variables to Reduce Automobile Travel (’95 M.S.)
- astrobiology
- biogeochemistry
- biometeorology
- biosphere-atmosphere interactions
- climate change
- ecohydrology
- GCMs
- general circulation models
- land surface models
- land use
- modeling
- paleoclimate
- photosynthesis
- plant ecophysiology
- terrestrial ecosystem science
- transportation energy use