Geothermal power plants of the United States: a technical survey of existing and planned installations

This study presents a framework to include environmental externalities into a system of national accounts. The paper estimates the air pollution damages for each industry in the United States. An integrated-assessment model quantifies the marginal damages of air pollution emissions for the US which are multiplied times the quantity of emissions by industry to compute gross damages. Solid waste combustion, sewage treatment, stone quarrying, marinas, and oil and coal-fired power plants have air pollution damages larger than their value added. The largest industrial contributor to external costs is coal-fired electric generation, whose damages range from 0.8 to 5.6 times value added. (JEL E01, L94, Q53, Q56)

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Fingerprints of a New Normal Urban Air Quality in S5P TROPOMI Tropospheric NO2 Observations

10.5194/egusphere-egu21-16363 ◽

2021 ◽

Author(s):

Shobha Kondragunta

Keyword(s):

United States ◽

Air Quality ◽

Unemployment Rate ◽

Power Plants ◽

The United States ◽

Urban Air Quality ◽

Urban Air ◽

Nox Emissions ◽

Percentage Increase ◽

New Normal

Most countries around the world took actions to control COVID-19 spread that included social distancing, limiting air and ground travel, closing schools, suspending sports leagues, closing factories etc., leading to&#160; economic shutdown. The reduced traffic and human movement compared to Business as Usual (BAU) scenario was tracked by Apple and Android cellphone use; the data showed substantial reductions in mobility in most metropolitan areas.&#160; We analyzed reductions in on-road mobile NOx emissions from light and heavy duty vehicles in four major metropolitan and one rural areas in the United States that showed a reduction in NOx mobile emissions from 9% to 19% between February and March at the onset of lockdown in the middle of March; between March and April, the mobile NOx emissions dropped further by 8% to 31% when lockdown measures were the most stringiest.&#160; These precipitous drops in NOx emissions correlated well with tropospheric NO2 column amount observed by Sentinel 5 Precursor TROPospheric Ozone Monitoring Instrument (S5P TROPOMI).&#160; Further, the changes in TROPOMI tropospheric NO2 across the continental U.S. between 2020 and 2019 correlated well with changes in on-road NOx emissions (r=0.78) but correlated weakly with changes in emissions from the power plants (r=0.44). These findings confirm that power plants are no longer the major source of NO2 in the United States. We also examined correlation between increase in unemployment rate between 2020 and 2019 to decrease in tropospheric NO2 amount.&#160; The negative correlation indicates that with increased unemployment rate combined with telework policies across the nation for non-essential workers, the NO2 values decreased at the rate of 0.8 &#181;moles/m2 decrease per unit percentage increase in unemployment rate.&#160; There is a substantial amount of scatter in the data with some cities such as Atlanta, Dallas, and Houston showing no noticeable trend in tropospheric NO2 changes during the time period when unemployment rate increased from 6% to 12%.&#160;&#160; We examined the trends in on-road and power plant emissions for five different locations (four urban areas and one rural area) and show that the changes in NOx emissions during the lockdown are detectable in TROPOMI tropNO2 data, the economic indicators are consistent with emissions changes, and the trends reversing with the removal of lockdown measures in the major metro areas have not come back to pre-pandemic levels.&#160; The COVID-19 pandemic experience has provided the scientific community an opportunity to identify emissions reductions scenarios that created a new normal for urban air quality and if the environmental protection agencies should look at this new normal as a guidance for instituting new policies.&#160;

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Baseload power potential from optimally-configured wind, solar and storage power plants across the United States

10.21203/rs.3.rs-86826/v1 ◽

2020 ◽

Author(s):

Joshua D Rhodes ◽

Aditya Choukulkar ◽

Brianna Cote ◽

Sarah A McKee ◽

Christopher T M Clack

Keyword(s):

United States ◽

Energy Storage ◽

Power Plants ◽

Cost Optimization ◽

The United States ◽

Solar Pv ◽

Wholesale Market ◽

Optimal Technology ◽

Current Price ◽

The Cost

Abstract In the present paper, we assessed the potential for local wind, solar PV, and energy storage to provide baseload (constant, uninterrupted) power in every county of the contiguous United States. The amount of available capacity between 2020 and 2050 was determined via a least-cost optimization model that took into account changing costs of constituent technologies and local meteorological conditions. We found that, by 2050, the potential exists for about 6.8 TW of renewable baseload power at an average cost of approximately $50 / MWh, which is competitive with current wholesale market rates for electricity. The optimal technology configurations constructed always resulted in over two hours of emergency energy reserves, with the amount increasing as the price of energy storage falls. We also found that, given current price decline trajectories, the model has a tendency to select more solar capacity than wind over time. A second part of the study performed three million simulations followed by a regression analysis to generate an online map-based tool that allows users to change input costs assumptions and compute the cost of renewable baseload electricity in every contiguous US county.

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Compound Hybrid Geothermal-Fossil Power Plants: Thermodynamic Analyses and Site-Specific Applications

Journal of Engineering for Power ◽

10.1115/1.3230804 ◽

1981 ◽

Vol 103 (4) ◽

pp. 797-804 ◽

Cited By ~ 7

Author(s):

Ronald DiPippo ◽

Eileen A. DiPippo ◽

Joseph Kestin ◽

H. E. Khalifa

Keyword(s):

United States ◽

Hybrid Systems ◽

Power Plants ◽

Western United States ◽

Fossil Plants ◽

Two Stage ◽

Site Specific ◽

Hybrid Plants ◽

Geothermal Power ◽

The One

In this paper, we extend the analysis of hybrid fossil-geothermal power plants to compound systems which combine the features of the two previously analyzed hybrid plants, the geothermal preheat and the fossil superheat systems. Compound systems of the one- and two-stage type are considered. A complete summary of formulae to assess the performance of the plants is included for completeness. From the viewpoint of thermodynamics, compound hybrid plants are superior to individual all-geothermal and all-fossil plants, and have certain advantages over basic geothermal-preheat and fossil-superheat hybrid plants. The flexibility of compound hybrid systems is illustrated by showing how such plants might be used at several geothermal sites in the western United States.

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Digital Instrumentation and Control Systems Upgrades in Current Generation Nuclear Power Plants

18th International Conference on Nuclear Engineering: Volume 1 ◽

10.1115/icone18-30358 ◽

2010 ◽

Author(s):

Steven A. Arndt

Keyword(s):

United States ◽

Cyber Security ◽

Nuclear Power ◽

Power Plants ◽

Nuclear Power Plants ◽

Plant Protection ◽

The United States ◽

Regulatory Compliance ◽

Digital Systems

Over the past 20 years, the nuclear power industry in the United States (U.S.) has been slowly replacing old, obsolete, and difficult-to-maintain analog technology for its nuclear power plant protection, control, and instrumentation systems with digital systems. The advantages of digital technology, including more accurate and stable measurements and the ability to improve diagnostics capability and system reliability, have led to an ever increasing move to complete these upgrades. Because of the difficulties with establishing digital systems safety based on analysis or tests, the safety demonstration for these systems relies heavily on establishing the quality of the design and development of the hardware and software. In the United States, the U.S. Nuclear Regulatory Commission (NRC) has established detailed guidelines for establishing and documenting an appropriate safety demonstration for digital systems in NUREG-0800, “Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants: LWR Edition,” Chapter 7, “Instrumentation and Controls,” Revision 5, issued March 2007 [1], and in a number of regulatory guides and interim staff guidance documents. However, despite the fact that the United States has a well-defined review process, a number of significant challenges associated with the design, licensing, and implementation of upgrades to digital systems for U.S. plants have emerged. Among these challenges have been problems with the quality of the systems and the supporting software verification and validation (V&V) processes, challenges with determining the optimum balance between the enhanced capabilities for the new systems and the desire to maintain system simplicity, challenges with cyber security, and challenges with developing the information needed to support the review of new systems for regulatory compliance.

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