scholarly journals PV System Predictive Maintenance: Challenges, Current Approaches, and Opportunities

Energies ◽  
2020 ◽  
Vol 13 (6) ◽  
pp. 1398 ◽  
Author(s):  
Lisa B. Bosman ◽  
Walter D. Leon-Salas ◽  
William Hutzel ◽  
Esteban A. Soto
Keyword(s):  
Solar Energy ◽  
The United States ◽  
Predictive Maintenance ◽  
Third Party ◽  
System Level ◽  
Pv System ◽  
Actual Performance ◽  
Call To Action ◽  
Expected Performance ◽  
Solar Energy Industry

Within the United States solar energy industry, there is a general motto of “set it and forget it” with solar energy. This notion is derived from much of the research and reliability studies around the photovoltaic (PV) panels themselves, not necessarily the PV system as a whole (including the inverter and other components). This implies that maintenance and regular monitoring is not needed. Yet many things can go wrong to cause the actual performance to deviate from the expected performance. If failures and/or unanticipated degradation issues go undetected, they will lead to reduced energy generation (and associated electricity credits) and/or potential loss of component warranty because of manufacturer turnover. Given the size of the problem and gaps with current solutions, the authors propose that PV system owners need an unbiased third-party off-the-shelf system-level predictive maintenance tool to optimize return-on-investment and minimize time to warranty claim in PV installations. This paper reviews the literature highlighting challenges, current approaches, and opportunities for PV predictive maintenance. The paper concludes with a call to action for establishing a collaborative agenda toward prioritizing PV predictive maintenance.

Diminishing Barriers to the Praxis Examination in Communication Sciences and Disorders

2011 ◽  
Vol 1 (2) ◽  
pp. 64-71
Author(s):  
Luis F. Riquelme
Keyword(s):  
Geographic Location ◽  
The United States ◽  
Success For All ◽  
Speech Language Pathology ◽  
Barriers To Success ◽  
Call To Action ◽  
Language Pathology ◽  
National Certification ◽  
Race Ethnicity ◽  
Passing Score

Abstract Passing the Praxis Examination in speech-language pathology or audiology can be a difficult task. A passing score is the entry to a list of requirements for national certification (CCC-SLP, CCC-A) and for state licensure in the United States. This article will provide current information on the examination and address barriers to success that have been identified over the years. A call to action may serve to refocus efforts on improving access to success for all test-takers regardless of race/ethnicity, ability, or geographic location.

Solar Renewable Energy Credit Price Volatility and Investment Returns: Have Policies Stranded Capital Investment?

Commonwealth ◽  
2017 ◽  
Vol 19 (1) ◽  
Author(s):  
Somayeh Youssefi ◽  
Patrick L. Gurian
Keyword(s):  
Solar Energy ◽  
Capital Investment ◽  
Supply And Demand ◽  
Price Volatility ◽  
The United States ◽  
Investment Model ◽  
Capital Investments ◽  
Demand Model ◽  
Market Prices ◽  
Investment Returns

Pennsylvania is one of a number of U.S. states that provide incentives for the generation of electricity by solar energy through Solar Renewal Energy Credits (SRECs). This article develops a return on investment model for solar energy generation in the PJM (mid-­Atlantic) region of the United States. Model results indicate that SREC values of roughly $150 are needed for residential scale systems to break even over a 25-­year project period at 3% interest. Market prices for SRECs in Pennsylvania have been well below this range from late 2011 through the first half of 2016, indicating that previous capital investments in solar generation have been stranded as a result of steep declines in the value of SRECs. A simple conceptual supply and demand model is developed to explain the sharp decline in market prices for SRECs. Also discussed is a possible policy remedy that would add unsold SRECs in a given year to the SREC quota for the subsequent year.

Systematic Government Access to Private-Sector Data in the United States I

2017 ◽  
Author(s):  
Stephanie K. Pell
Keyword(s):  
Private Sector ◽  
Public Information ◽  
The United States ◽  
Third Party ◽  
Threat Detection ◽  
Detection And Identification ◽  
Potential Applications ◽  
September 11 Attacks ◽  
Access To Data ◽  
Sector Data

After the September 11 attacks, law enforcement's mission expanded to include, at times even prioritize, the general “prevention, deterrence and disruption” of terrorist attacks, which presumed a new emphasis upon threat detection and identification by analyzing patterns in larger, less specific bodies of information. Indeed, the unprecedented level of “third-party” possession of information inevitably makes the private sector the most reliable and comprehensive source of information available to law enforcement and intelligence agencies alike. This chapter explores the potential applications of systematic government access to data held by third-party private-sector intermediaries that would not be considered public information sources but, rather, data generated based on the role these intermediaries play in facilitating economic and business transactions (including personal business, such as buying groceries or staying at a hotel on vacation).

Poisoned Earth

2017 ◽  
Author(s):  
Geoffrey Jones
Keyword(s):  
Solar Energy ◽  
Rural Areas ◽  
Small Firms ◽  
Social Activism ◽  
The United States ◽  
Oil Companies ◽  
Natural Beauty ◽  
Green Business ◽  
The 1960S ◽  
Start Ups

The chapter examines green business during the 1960s and 1970, decades of new environmental awareness. In organic food natural beauty, a number of commercially viable green businesses and brands began to be built, and distribution channels created. There was significant innovation in wind and solar energy in the wake of the first oil crises although they remained marginal in the energy industry. Green entrepreneurs still faced huge obstacles finding both capital and consumers. In the case of the capital-intensive solar energy business, the main solution was to sell start-ups to cash-rich oil companies. Green businesses clustered in hubs of environmental and social activism, such as Berkeley and Boulder in the United States, Allgäu in Germany, and rural areas of Denmark. These clusters enabled small firms to build skills and competences which could eventually be used to expand into more mainstream locations.

Lead in Mineral or Multivitamin-Multimineral Products

2021 ◽  
pp. 106002802110233
Author(s):  
C. Michael White
Keyword(s):  
English Language ◽  
Data Extraction ◽  
The United States ◽  
Third Party ◽  
Reference Level ◽  
Study Selection ◽  
Pubmed Search ◽  
Zinc Supplements ◽  
Average Lead ◽  
Year 2000

Objective Assess the current daily interim reference level of lead and the amount contained in current mineral and multivitamin-multimineral (MVM) products. Data Sources PubMed search from 1980 to May 15, 2021, limited to the English language, via the search strategy ((mineral OR multivitamin OR calcium OR iron OR magnesium OR copper OR zinc OR chromium OR selenium) AND (heavy metals OR Pb OR lead)). Study Selection and Data Extraction Narrative review of studies assessing lead content in mineral or MVM products. Data Synthesis Products containing different calcium forms (dolomite, bone meal, natural carbonate) have historically had higher lead levels than others (refined carbonate, lactate, gluconate, acetate, sevelamer), but the gap has closed considerably since the year 2000. Although only limited assessments of magnesium and zinc supplements have been conducted, no alarming average lead amounts were found. MVM products assessed since 2007 had low median or mean lead concentrations. However, large interproduct differences exist, with many products having very little lead and some products having concerning amounts. Relevance to Patient Care and Clinical Practice It is difficult for pharmacists and consumers to know the amount of lead in an actual product unless it is tested in an independent third-party lab. The United States Pharmacopeia and NSF International will provide a seal on the products stating that the products have a low level of lead, but even so, children could receive more lead than the Food and Drug Administration’s Interim Reference Level. Conclusions The threat from lead exposure in mineral and MVM products have diminsihed considerably over time but some products can still have excessive amounts. Without third-party testing, it is difficult for clinicians and consumers to know which outlier products to avoid.

Quantification of Solar Energy Grid Disturbances in the United States

2021 ◽  
Author(s):  
Esteban A. Soto ◽  
Lisa B. Bosman ◽  
Ebisa Wollega
Keyword(s):  
United States ◽  
Solar Energy ◽  
The United States ◽  
Energy Grid

Maximum Power Point Tracking (MPPT) for a Solar Photovoltaic System: A Review

2015 ◽  
Vol 787 ◽  
pp. 227-232 ◽  
Author(s):  
L.A. Arun Shravan ◽  
D. Ebenezer
Keyword(s):  
Solar Energy ◽  
Maximum Power Point Tracking ◽  
Maximum Power ◽  
Nonlinear Behaviour ◽  
Pv System ◽  
Maximum Power Point ◽  
Pv Systems ◽  
Point Tracking ◽  
Power Point Tracking ◽  
Power Point

In recent years there has been a growing attention towards use of solar energy. Advantages of photovoltaic (PV) systems employed for harnessing solar energy are reduction of greenhouse gas emission, low maintenance costs, fewer limitations with regard to site of installation and absence of mechanical noise arising from moving parts. However, PV systems suffer from relatively low conversion efficiency. Therefore, maximum power point tracking (MPPT) for the solar array is essential in a PV system. The nonlinear behaviour of PV systems as well as variations of the maximum power point with solar irradiance level and temperature complicates the tracking of the maximum power point. This paper reviews various MPPT methods based on three categories: offline, online and hybrid methods. Design of a PV system in a encoding environment has also been reviewed here. Furthermore, different MPPT methods are discussed in terms of the dynamic response of the PV system to variations in temperature and irradiance, attainable efficiency, and implementation considerations.

scholarly journals Development of Packaging and Modular Control of Thermoelectric Clothes Dryer, With Performance Evaluation

2017 ◽  
Author(s):  
Viral K. Patel ◽  
Kyle R. Gluesenkamp
Keyword(s):  
Energy Consumption ◽  
Heat Pump ◽  
Minimum Energy ◽  
Experimental System ◽  
The United States ◽  
Primary Energy ◽  
System Level ◽  
Clothes Dryer ◽  
Thermoelectric Heat Pump ◽  
Thermoelectric Heat

This paper provides an overview of a thermoelectric heat pump clothes dryer which was developed with the aim of reducing the significant primary energy consumption attributed to residential electric clothes drying in the United States (623 TBtu/yr). The use of thermoelectric modules in place of the conventional electric resistance heater resulted in a 40% reduction in the energy consumption of the system, compared to the minimum energy efficiency standard. This was achieved for the first time for a standard test load of 8.45 lb, using a clothes dryer prototype with a thermoelectric heat pump module as the sole heating mechanism. The current experimental prototype was developed after extensive modeling, system design and control optimization, and experimental system-level evaluation of control parameters. The demonstration of improved energy consumption has laid the foundation for future development of this technology.

scholarly journals Stemming the Tide of Suicide in Older White Men: A Call to Action

2008 ◽  
Vol 3 (3) ◽  
pp. 189-200 ◽  
Author(s):  
Timothy Schmutte ◽  
Maria O'Connell ◽  
Melissa Weiland ◽  
Samuel Lawless ◽  
Larry Davidson
Keyword(s):  
United States ◽  
Baby Boom ◽  
Public Health Problem ◽  
White Men ◽  
The United States ◽  
Prevention Strategies ◽  
Call To Action ◽  
National Crisis ◽  
National Priority ◽  
Past Half Century

Preventing suicide has been identified as a national priority by recent commissions in the United States. Despite increased awareness of suicide as a public health problem, suicide in older adults remains a neglected topic in prevention strategies and research. This is especially true regarding elderly White men, who in terms of suicide rates have represented the most at-risk age group for the past half century. In light of the unprecedented aging of the United States as the baby boom generation enters late adulthood, suicide prevention initiatives that focus on aging males are needed to prevent a national crisis in geriatric mental health. This article provides a brief review of the perennially under-recognized reality of suicide in older men and prevention strategies that, if implemented, might help stem this rising tide of suicide in this vulnerable population.

Sign in / Sign up

Export Citation Format

Share Document