Deploy diverse renewables to save tropical rivers.

A strategic mix of solar, wind and storage technologies around river basins would be safer and cheaper than building large dams, argue Rafael J. P. Schmitt, Noah Kittner and colleagues

Operational grid and environmental impacts for a V2G-enabled electric school bus fleet using DC fast chargers

As states replace diesel school buses with electric ones, utilities will want to control charging schedules to capture potential benefits on the grid and avoid all buses charging at the same time, adding a large electric load. Vehicle-to-grid (V2G) services can provide more grid stability and reduced carbon dioxide emissions than simple controlled charging systems, yet the grid impacts of V2G school buses have not been modeled using realistic school bus schedules. This paper develops a methodology for simulating the effect of managed charging of electric school buses on peak shaving in the state of North Carolina using V2G interactions and DC fast chargers to determine potential emissions reductions by minimizing peak load periods. The V2G-Sim model is used to manage fleet-wide charging, while minimizing peak generation of electricity on the grid and flattening the load curve under different battery capacities, charger power ratings, and fleet sizes. Historic annual peak hours are examined to determine the feasibility of reducing generation capacity, and the daily peak hours are examined to determine the potential peak shaving and subsequent avoided emissions. The results demonstrate that at full electric school bus replacement, 14,000 V2G buses can aggregate and shift 2.6 GWh in North Carolina, avoiding up to 1,130 t of carbon dioxide emissions per day, assuming decreased dependence on natural gas peaker plants. An additional 1,500 t of CO2 can be avoided by replacing diesel-powered buses compared to the 320,000 t total daily CO2 emissions from all activities in North Carolina. Additional emissions are avoided by the replacement of diesel buses with electric buses. The largest greenhouse gas emission benefit is the replacement of diesel with electric school buses, and the ability to shave peak loads is maximized on weekend days in the winter. The model can be used by researchers, the utility, and states as these entities evaluate the environmental and operational grid benefits of a V2G school bus program

Estimating PEM Electrolyzer Costs for Hydrogen Production Through 2050

Hydrogen from water electrolysis will play a key role in the transition to a decarbonized energy system. For green hydrogen to reach production on mass scales, the CAPEX or $/kW cost of hydrogen production, needs to fall by as large as a factor of 6. In this analysis, multiple cost projections were analyzed from academia, industry, and government examples of PEM hydrogen production to determine historical learning rates. PEM electrolyzers were chosen specifically for this study given their emerging cost competitiveness and efficiency improvement potential and industry support when compared to competing hydrogen electrolyzer types. The learning rates are applied to current costs and projected under multiple deployment scenarios with the purpose of predicting hydrogen costs through the year 2050. Out of 45 scenarios, the lower bound scenario is 16.2 magnitudes less CAPEX for PEM electrolyzers in 2050 than the starting scenario CAPEX in 2022. On the other hand, the results of the model find the upper bound scenario for PEM electrolyzer CAPEX in 2050 to be 2.4 magnitudes less than the starting scenario CAPEX in 2022. Regardless of scenario, there is evidence to suggest that the greatest price decreases will take place between 2022 and 2030. For the most aggressive scenarios to become viable possibilities, there will need to be policies supporting hydrogen technologies, not only in terms of research and development, but also deployment for practical use cases

Cross-sector storage and modeling needed for deep decarbonization

As many researchers work to achieve a decarbonized grid, there is a general appreciation that we need to model the total energy system, but that doing so is difficult, if not impractical. Studies may focus on one piece of the grid and reach a conclusion whether a particular approach will or won’t work. Including cross-sector storage in modeling provides opportunities to enable solutions that are otherwise impossible to identify and that may become the key to reaching a lowest-cost, lowest-carbon energy system

Metabolomic profiles predict individual multidisease outcomes

Publisher Copyright: © 2022, The Author(s).Risk stratification is critical for the early identification of high-risk individuals and disease prevention. Here we explored the potential of nuclear magnetic resonance (NMR) spectroscopy-derived metabolomic profiles to inform on multidisease risk beyond conventional clinical predictors for the onset of 24 common conditions, including metabolic, vascular, respiratory, musculoskeletal and neurological diseases and cancers. Specifically, we trained a neural network to learn disease-specific metabolomic states from 168 circulating metabolic markers measured in 117,981 participants with ~1.4 million person-years of follow-up from the UK Biobank and validated the model in four independent cohorts. We found metabolomic states to be associated with incident event rates in all the investigated conditions, except breast cancer. For 10-year outcome prediction for 15 endpoints, with and without established metabolic contribution, a combination of age and sex and the metabolomic state equaled or outperformed established predictors. Moreover, metabolomic state added predictive information over comprehensive clinical variables for eight common diseases, including type 2 diabetes, dementia and heart failure. Decision curve analyses showed that predictive improvements translated into clinical utility for a wide range of potential decision thresholds. Taken together, our study demonstrates both the potential and limitations of NMR-derived metabolomic profiles as a multidisease assay to inform on the risk of many common diseases simultaneously.Peer reviewe

Energy Systems Integration and Innovation for a Clean Energy Transition

This dissertation presents a set of analytical tools developed to investigate the energy system transition using a systems approach. The cases explored range from Kosovo, a country on the verge of new electricity supply investments, and future energy pathways to an analytical investigation of innovation in battery storage systems that could unlock the environmental and health benefits of intermittent renewable energy sources such as solar and wind technologies. The analytical tools compare existing metrics such as levelized cost of electricity with new metrics such as a two-factor learning curve of deployment and innovation and trace metal content of coal per final kWh of electricity delivered and energy return on investment of distributed energy systems.Chapter 1 investigates the case of Kosovo and introduces an analytic framework to analyze electricity costs and environmental impacts of future electricity options. The scheduled decommissioning of the Kosovo A coal-fired power plant provides an opportunity to investigate the changing cost of alternative energy options available in Kosovo for new energy infrastructure. I find that a range of investment pathways from international financial institutions and donor groups could meet the same projected electricity demand at a lower cost than building a new 600 MW coal fired power plant. The options include energy efficiency measures, combinations of solar PV, wind, hydropower, biomass, and the introduction of natural gas. The results indicate that financing a new coal plant is the most expensive pathway to meet future electricity demand in Kosovo.Chapter 2 utilizes the analytic framework developed to estimate the cost of future electricity pathways and uses green chemistry and public health risk assessment to estimate trace metal content of coal and investigate the air-pollution-related-health risks of lignite coal in Kosovo. By utilizing ICP-MS, I sample lignite coal for trace metal content and develop a risk model to assess future health impacts of air pollution from the electricity options explored in Chapter 1. I find significant trace metal content normalized per kWh of final electricity delivered. I estimate that Kosovo could avoid 2300 premature deaths by 2030 when introducing energy efficiency and solar PV backed up by natural gas. The framework highlights that often multi-lateral development banks do not account for all health risks before guaranteeing loans on new electricity projects. The interest in finding sustainable options to balance the load of intermittent renewable energy options in Kosovo motivates further analysis to understand how battery storage technologies have developed over time in terms of performance and cost.Chapter 3 examines the dramatically falling cost of battery storage options. I develop a two- factor technological learning curve model that integrates the value of investment in materials innovation and technology deployment over time from an empirical dataset covering battery storage technology. I find and chart a viable path to dispatchable $1/W solar with$100/kWh battery storage that enables combinations of solar, wind, and storage to compete directly with fossil fuel-based electricity options. I highlight the co-evolutionary nature of the cost reductions of battery storage technologies and suggest the relative importance of sustained investment and integration of R&D and deployment to develop innovative low-carbon combined solar, storage, and wind systems.Chapter 4 highlights the changing energy return on investment of energy technologies by investigating a case in Thailand where distributed solar, mini-hydro, and battery storage mini- grids are becoming an attractive investment and serve as core options to meet growing demand for electricity. I compare the net energy return on investment (EROI) of mini-hydropower, solar PV, and battery storage. This study represents a direct application of the opportunities for battery storage technologies to enable cost-competitive mini-grids in Thailand and around the world.The dissertation highlights different plans, designs, and future management of cost-effective, sustainable, and healthy electricity systems for a clean energy transition worldwide. The analytical tools presented combine to integrate traditional economic, environmental, and health metrics into energy systems planning and innovation. By integrating these interconnected systems, it becomes possible to enable cleaner and more sustainable energy transitions

Energy Systems Integration and Innovation for a Clean Energy Transition

This dissertation presents a set of analytical tools developed to investigate the energy system transition using a systems approach. The cases explored range from Kosovo, a country on the verge of new electricity supply investments, and future energy pathways to an analytical investigation of innovation in battery storage systems that could unlock the environmental and health benefits of intermittent renewable energy sources such as solar and wind technologies. The analytical tools compare existing metrics such as levelized cost of electricity with new metrics such as a two-factor learning curve of deployment and innovation and trace metal content of coal per final kWh of electricity delivered and energy return on investment of distributed energy systems.Chapter 1 investigates the case of Kosovo and introduces an analytic framework to analyze electricity costs and environmental impacts of future electricity options. The scheduled decommissioning of the Kosovo A coal-fired power plant provides an opportunity to investigate the changing cost of alternative energy options available in Kosovo for new energy infrastructure. I find that a range of investment pathways from international financial institutions and donor groups could meet the same projected electricity demand at a lower cost than building a new 600 MW coal fired power plant. The options include energy efficiency measures, combinations of solar PV, wind, hydropower, biomass, and the introduction of natural gas. The results indicate that financing a new coal plant is the most expensive pathway to meet future electricity demand in Kosovo.Chapter 2 utilizes the analytic framework developed to estimate the cost of future electricity pathways and uses green chemistry and public health risk assessment to estimate trace metal content of coal and investigate the air-pollution-related-health risks of lignite coal in Kosovo. By utilizing ICP-MS, I sample lignite coal for trace metal content and develop a risk model to assess future health impacts of air pollution from the electricity options explored in Chapter 1. I find significant trace metal content normalized per kWh of final electricity delivered. I estimate that Kosovo could avoid 2300 premature deaths by 2030 when introducing energy efficiency and solar PV backed up by natural gas. The framework highlights that often multi-lateral development banks do not account for all health risks before guaranteeing loans on new electricity projects. The interest in finding sustainable options to balance the load of intermittent renewable energy options in Kosovo motivates further analysis to understand how battery storage technologies have developed over time in terms of performance and cost.Chapter 3 examines the dramatically falling cost of battery storage options. I develop a two- factor technological learning curve model that integrates the value of investment in materials innovation and technology deployment over time from an empirical dataset covering battery storage technology. I find and chart a viable path to dispatchable $1/W solar with$100/kWh battery storage that enables combinations of solar, wind, and storage to compete directly with fossil fuel-based electricity options. I highlight the co-evolutionary nature of the cost reductions of battery storage technologies and suggest the relative importance of sustained investment and integration of R&D and deployment to develop innovative low-carbon combined solar, storage, and wind systems.Chapter 4 highlights the changing energy return on investment of energy technologies by investigating a case in Thailand where distributed solar, mini-hydro, and battery storage mini- grids are becoming an attractive investment and serve as core options to meet growing demand for electricity. I compare the net energy return on investment (EROI) of mini-hydropower, solar PV, and battery storage. This study represents a direct application of the opportunities for battery storage technologies to enable cost-competitive mini-grids in Thailand and around the world.The dissertation highlights different plans, designs, and future management of cost-effective, sustainable, and healthy electricity systems for a clean energy transition worldwide. The analytical tools presented combine to integrate traditional economic, environmental, and health metrics into energy systems planning and innovation. By integrating these interconnected systems, it becomes possible to enable cleaner and more sustainable energy transitions

High-resolution electricity generation model demonstrates suitability of high-altitude floating solar power

This paper develops a meteorological site selection algorithm to quantify the electricity generation potential of floating solar design configurations on alpine water bodies in Switzerland. Using European power market demand patterns, we estimate the technical and economic potential of 82 prospective high-altitude floating solar sites co-located with existing Swiss hydropower. We demonstrate that the amount of solar energy radiating from high-altitude Swiss water bodies could meet total national electricity demand while significantly reducing carbon emissions and addressing seasonal supply/demand deficits. We construct a global map overlaying sites on each continent where high-altitude floating solar could provide low-carbon, land-sparing electricity. Our results present a compelling motivation to develop alpine floating solar installations. However, significant innovations are still needed to couple floating solar with existing hydropower operations or low-cost energy storage. As the industry matures, high-altitude floating solar technology could become a high-value, low-carbon electricity source.ISSN:2589-004