B.S. ​University of Virginia, 1999M.S. ​University of Michigan, 2004Ph.D. ​University of Michigan, 2008

"Our group is focused on developing engineering tools that can support the decarbonization of our built environment."

Andres Clarens, Professor

Andrés Clarens is a Professor of Civil and Environmental Engineering at the University of Virginia and Aasociate Director of the Pan-University Environmental Resilience Institutue. His research is focused broadly on understanding anthropogenic carbon flows and the ways that CO2 is manipulated, reused, and sequestered in engineered systems. The results of his work are important for developing efficient strategies for mitigating the emissions that are driving climate change. At the largest scales, his system-level modeling work has explored the life cycle of systems in the manufacturing, transportation, and energy sectors. In the laboratory, he is pursuing complementary research in the phase behavior and surface chemistry of carbon dioxide mixtures at high pressure.

This work can be used to provide low carbon cements and more effective predictive tools for understanding tradeoffs between energy systems and water systems. In the classroom, Prof. Clarens engages in peer-to-peer learning at both the undergraduate and graduate level with an emphasis on developing innovative tools for teaching the fundamentals of climate change. In his spare time, he enjoys running, fly fishing, backpacking, mountain biking, and traveling internationally.


  • Earth Leaders Program - Fellow 2022-23
  • United States Fulbright Fellow – National Technical University of Argentina 2016
  • National Academies of Science, Arab American Frontiers of Science, Engineering and Medicine - Participant 2014
  • National Science Foundation CAREER Award 2013-2018
  • Department Teaching Award – UVa Civil and Environmental Engineering 2013
  • American Chemical Society Petroleum Research Fund Young Investigator Award 2010-2012
  • Fund for Excellence in Science and Technology – UVa Vice President for Research Office Junior Faculty Award (w/ L. Colosi) 2010-2011

Research Interests

  • Environmental Engineering
  • Carbon Capture and Sequestration
  • Negative Emissions

Selected Publications

  • Quantification of mineral reactivity using machine learning interpretation of micro-XRF data ABS Kim, J. J., Ling, F. T., Plattenberger, D. A., Clarens, A. F., & Peters, C. A. (2022). Applied Geochemistry, 136, 105162.
  • Techno-economic analysis of offshore isothermal compressed air energy storage in saline aquifers co-located with wind power. ABS Bennett, J. A., Simpson, J. G., Qin, C., Fittro, R., Koenig Jr, G. M., Clarens, A. F., & Loth, E. (2021). Applied Energy, 303, 117
  • The role of direct air capture and negative emissions technologies in the shared socioeconomic pathways towards+ 1.5° C and+ 2° C futures. ABS Fuhrman, J., Clarens, A., Calvin, K., Doney, S. C., Edmonds, J. A., O’Rourke, P., & McJeon, H. (2021) Environmental Research Letters, 16(11), 114012.
  • Extending energy system modelling to include extreme weather risks and application to hurricane events in Puerto Rico ABS J. Bennett1, C. Trevisan, J. DeCarolis, C. Ortiz, M. Perez Lugo, B. Etienne, A. Clarens (2021) Nature Energy 6(3), 240-249
  • Food–energy–water implications of negative emissions technologies in a+ 1.5° C future ABS J Fuhrman, H McJeon, P Patel, SC Doney, WM Shobe, AF Clarens (2020) Nature Climate Change, 1-8
  • Feasibility of Using Calcium Silicate Carbonation to Synthesize High-Performance and Low-Carbon Cements ABS DA Plattenberger, EJ Opila, R Shahsavari, AF Clarens (2020) ACS Sustainable Chemistry & Engineering 8 (14), 5431-5436

Courses Taught

  • CEE 1620 - Introduction to Engineering
  • CEE 2100 - Introduction to Environmental Engineering
  • CEE 3050 - Introduction to Green Engineering
  • CEE 4110-6220 - Water Chemistry
  • CEE 4500-6020 - Green Engineering and Sustainability
  • CEE 6500 - Physicochemical Processes

Featured Grants & Projects

  • High Performance and Low Emissions Cementitious Materials

    Ordinary Portland cement (OPC) production is the second most energy intensive industrial sector in the United States (after electricity production) because of the extremely high temperatures (~1450ºC) that are required to treat the limestone feedstock. Our team is developing novel pathways to make high-strength, low-permeability, high durability materials with only a fraction of the energy and emissions that come from OPC. Our patent-pending processes are inspired by the carbonation of calcium silicate (CaSiO3) feedstocks but would be flexible to allow substitution depending on feedstock availability. We are translating our production process to large scale using inexpensive mineral feedstocks and waste materials such as industrial slag, fly ash, and/or waste heat and CO2 in flue gas streams. Our congruent calcium concentration via controlled carbonation (C5) cements are rich in crystalline calcium silicate hydrate (CCSH) mineral phases with some similarities to those that give ancient Roman cements much of its remarkable strength and durability. These product phases are abundant and can be tailored to the end use by controlling the feedstock chemistry and the curing conditions. Our project is developing the chemical understanding needed to leverage this chemistry as enabling for a range of high-value add applications in infrastructure, energy, and building. Our team is also developing the flask-to-field engineering knowledge needed to deliver viable products for a range of applications.

  • Modeling the Impacts of Negative Emissions Technologies Across Scales

    Plans to limit the impacts of climate change increasingly include forms of carbon dioxide removal, a new but important complement to existing efforts to decarbonize our economy. Negative emissions technologies include approaches like bioenergy with carbon capture, enhanced uptake of soil carbon, reforestation, and direct air capture of CO2. Our group is modeling these processes and working to understand this emergent class of carbon removal strategies, the co-benefits and tradeoffs they could present. We are working using the Global Change Assessment Model and other regional energy systems models to develop full cost-accounting of co-benefits and tradeoffs of deep decarbonization to include ecosystem services (fresh water supplies, flood protection, food production, air quality), human wellbeing (disparities in health outcomes), economic competitiveness (workforce), and equity (housing, transportation costs).

  • Gas leakage in geologic carbon storage and hydraulic fracturing

    Subsurface fluid injections associated with geologic carbon storage or hydraulic fracturing are likely to lead to increases in pore pressure that would drive transport into overlying formations. We are working to develop a fundamental understanding of how interfacial properties at the gas-brine interface and at the gas-brine-mineral interface could impact buoyancy driven flow through porous media. Mass transfer between gas (e.g., CO2) and brine and CO2 phase change will mitigate leakage as illustrated below. These results are being used to develop improved frameworks of CO2 transport through porous media in brine and will ultimately lead to improved guidelines and recommendations for site selection, leakage prevention and operating conditions.

  • Reducing the environmental impacts of hydraulic fracturing

    Recent advances in directional drilling and hydraulic fracturing of low permeability formations have led to a boom in hydrocarbon production from shale formations. There is growing concern that these practices can lead to a number of environmental problems and we are pursuing several activities in our lab to try and mitigate some of these impacts. In particular, we are exploring the fundamental rheology and chemical formulation principles that will be needed to deploy energized fluids made of CO2 to eliminate the water all together. Separately we are working on developing the chemistry to deploy reactive proppants that could be removed at the end of gas production to minimize long term risks and to store carbon.