Neal Dowling - Academia.edu (original) (raw)
Papers by Neal Dowling
2010 IEEE Conference on Innovative Technologies for an Efficient and Reliable Electricity Supply, 2010
... Zoot Enterprises CEO Chris Nelson expected the fuel cells to provide continuous power during ... more ... Zoot Enterprises CEO Chris Nelson expected the fuel cells to provide continuous power during utility outages, but he was disappointed. ... The level of supervision and review required for testing increases as the tests progress from simulation, desktop, benchtop, and full power. ...
Journal of applied physiology: respiratory, environmental and exercise physiology
The increased minute ventilation (VE) associated with exercise produces similar degrees of airway... more The increased minute ventilation (VE) associated with exercise produces similar degrees of airway cooling in normal and asthmatic subjects, but only those with asthma develop postexertional bronchoconstriction in response to this stimulus. We have found that when normal subjects breathing subfreezing air perform isocapnic hyperventilation to levels exceeding those associated with even exhausting exercise, 1-s forced expiratory volumes and maximum midexpiratory flow rates fall significantly. When tests more sensitive in detecting bronchoconstriction are employed, changes are seen at lower levels of hyperventilation that simulate the VE associated with moderately heavy work loads. We conclude that normal subjects respond to airway cooling, but are much less sensitive than those with asthma.
PowerSecure (PS), a subsidiary of Southern Company, operates over 1600 microgrids and as a result... more PowerSecure (PS), a subsidiary of Southern Company, operates over 1600 microgrids and as a result manages a large fleet of standby diesel generators. The machines range in power from 125 to 2800 kW. Most machines in the fleet are used in two different missions. In addition to providing standby power after utility failure, most machines serve one or more utility-driven load management applications, including demand response, coincident peak capacity markets, automatic frequency response, and generation during peak spot market prices. MTechnology, Inc., was retained to study the fleet reliability. We began by assessing the reliability of the fleet in 2011. At that time the reliability was 95%, consistent with previously published studies [1] [2] This study counts all failures and excludes none, unlike some previous studies which exclude more than half of observed failures. The intention of this study is to show reliability as experienced by customers. The fleet reliability for outage ...
IEEE Transactions on Industry Applications, 2016
IEEE Transactions on Industry Applications, 2016
IEEE Transactions on Industry Applications
PowerSecure (PS), a subsidiary of Southern Company, operates over 1600 microgrids including a lar... more PowerSecure (PS), a subsidiary of Southern Company, operates over 1600 microgrids including a large fleet of standby diesel generators. Machines range from 125 to 2800 kW. There are two missions: standby power after utility failure, and load management when utility is available. This report updates generator reliability data published over 20 years ago. These results are the first derived from uniform records from a distributed data acquisition system. The unique aspects of this effort include automated data collection, analysis and storage producing a standardized record for all machines and events. This greatly reduces the effort required to prepare reports and analysis. Automated collection largely eliminates human errors in data entry, and prevents post-hoc adjustment of mission success or failure. We are not aware of previous published generator data using automated data acquisition. This study counts all failures and excludes none, while previous studies exclude more than half. This analysis expresses reliability as experienced by customers. The number of machines, years in service, and years of operation greatly exceed the sum of previous published studies, enabling calculation of useful confidence limits. The fleet is heterogenous with machines from over a dozen manufacturers and many power ratings. Machine reliability was consistent across brands, and there is no significant difference in reliability for different size machines. This common assumption was not supported by prior studies. High quality data enables reliability growth management practices. The fleet reliability for outage demands of all durations increased from 95% in 2011 to 98% in 2014-18. Analysis of failures arrival time shows that failure rate is strongly dependent on mission duration. Failure rates after 14 hours are approximately 1% of the value for the first 30 minutes of operation. This has important implications for designing systems to meet specified reliability targets, and in interpreting and comparing results from fleets with different mission durations.
2015 IEEE Industry Applications Society Annual Meeting, 2015
2015 IEEE/IAS 51st Industrial & Commercial Power Systems Technical Conference (I&CPS), 2015
IEEE Transactions on Industry Applications, 2014
2010 IEEE Conference on Innovative Technologies for an Efficient and Reliable Electricity Supply, 2010
A power plant comprising two 200 kW/230 kVA fuel cells was installed and operated over a period o... more A power plant comprising two 200 kW/230 kVA fuel cells was installed and operated over a period of 15 months. Details of the operating experience and economics of the application are discussed.
IEEE Transactions on Industry Applications, 2000
Industrial and Commercial Power Systems Technical Conference, Annual Meeting, 2012
One of the most common questions in the early stages of designing a new facility is whether the n... more One of the most common questions in the early stages of designing a new facility is whether the normal utility supply to a fire pump is reliable enough to “tap ahead of the main” or whether the fire pump supply is so unreliable that it must have an emergency power source; typically an on-site generator. Apart from the obligation to
Industrial and Commercial Power Systems Technical Conference, Annual Meeting, 2012
One of the most common questions in the early stages of designing a new facility is whether the n... more One of the most common questions in the early stages of designing a new facility is whether the normal utility supply to a fire pump is reliable enough to “tap ahead of the main” or whether the fire pump supply is so unreliable that it must have an emergency power source; typically an on-site generator. Apart from the obligation to
2010 IEEE Conference on Innovative Technologies for an Efficient and Reliable Electricity Supply, 2010
2010 IEEE Conference on Innovative Technologies for an Efficient and Reliable Electricity Supply, 2010
A power plant comprising two 200 kW/230 kVA fuel cells was installed and operated over a period o... more A power plant comprising two 200 kW/230 kVA fuel cells was installed and operated over a period of 15 months. Details of the operating experience and economics of the application are discussed.
2014 IEEE Industry Application Society Annual Meeting, 2014
2010 IEEE Conference on Innovative Technologies for an Efficient and Reliable Electricity Supply, 2010
... operate motors can produce acceptable performance using only 2 current transducers and comput... more ... operate motors can produce acceptable performance using only 2 current transducers and computing the third phase current based upon balanced ... A high speed interactive two step method for detecting island conditions was analyzed and proposed for the power plant. ...
2010 IEEE Conference on Innovative Technologies for an Efficient and Reliable Electricity Supply, 2010
... Zoot Enterprises CEO Chris Nelson expected the fuel cells to provide continuous power during ... more ... Zoot Enterprises CEO Chris Nelson expected the fuel cells to provide continuous power during utility outages, but he was disappointed. ... The level of supervision and review required for testing increases as the tests progress from simulation, desktop, benchtop, and full power. ...
Journal of applied physiology: respiratory, environmental and exercise physiology
The increased minute ventilation (VE) associated with exercise produces similar degrees of airway... more The increased minute ventilation (VE) associated with exercise produces similar degrees of airway cooling in normal and asthmatic subjects, but only those with asthma develop postexertional bronchoconstriction in response to this stimulus. We have found that when normal subjects breathing subfreezing air perform isocapnic hyperventilation to levels exceeding those associated with even exhausting exercise, 1-s forced expiratory volumes and maximum midexpiratory flow rates fall significantly. When tests more sensitive in detecting bronchoconstriction are employed, changes are seen at lower levels of hyperventilation that simulate the VE associated with moderately heavy work loads. We conclude that normal subjects respond to airway cooling, but are much less sensitive than those with asthma.
PowerSecure (PS), a subsidiary of Southern Company, operates over 1600 microgrids and as a result... more PowerSecure (PS), a subsidiary of Southern Company, operates over 1600 microgrids and as a result manages a large fleet of standby diesel generators. The machines range in power from 125 to 2800 kW. Most machines in the fleet are used in two different missions. In addition to providing standby power after utility failure, most machines serve one or more utility-driven load management applications, including demand response, coincident peak capacity markets, automatic frequency response, and generation during peak spot market prices. MTechnology, Inc., was retained to study the fleet reliability. We began by assessing the reliability of the fleet in 2011. At that time the reliability was 95%, consistent with previously published studies [1] [2] This study counts all failures and excludes none, unlike some previous studies which exclude more than half of observed failures. The intention of this study is to show reliability as experienced by customers. The fleet reliability for outage ...
IEEE Transactions on Industry Applications, 2016
IEEE Transactions on Industry Applications, 2016
IEEE Transactions on Industry Applications
PowerSecure (PS), a subsidiary of Southern Company, operates over 1600 microgrids including a lar... more PowerSecure (PS), a subsidiary of Southern Company, operates over 1600 microgrids including a large fleet of standby diesel generators. Machines range from 125 to 2800 kW. There are two missions: standby power after utility failure, and load management when utility is available. This report updates generator reliability data published over 20 years ago. These results are the first derived from uniform records from a distributed data acquisition system. The unique aspects of this effort include automated data collection, analysis and storage producing a standardized record for all machines and events. This greatly reduces the effort required to prepare reports and analysis. Automated collection largely eliminates human errors in data entry, and prevents post-hoc adjustment of mission success or failure. We are not aware of previous published generator data using automated data acquisition. This study counts all failures and excludes none, while previous studies exclude more than half. This analysis expresses reliability as experienced by customers. The number of machines, years in service, and years of operation greatly exceed the sum of previous published studies, enabling calculation of useful confidence limits. The fleet is heterogenous with machines from over a dozen manufacturers and many power ratings. Machine reliability was consistent across brands, and there is no significant difference in reliability for different size machines. This common assumption was not supported by prior studies. High quality data enables reliability growth management practices. The fleet reliability for outage demands of all durations increased from 95% in 2011 to 98% in 2014-18. Analysis of failures arrival time shows that failure rate is strongly dependent on mission duration. Failure rates after 14 hours are approximately 1% of the value for the first 30 minutes of operation. This has important implications for designing systems to meet specified reliability targets, and in interpreting and comparing results from fleets with different mission durations.
2015 IEEE Industry Applications Society Annual Meeting, 2015
2015 IEEE/IAS 51st Industrial & Commercial Power Systems Technical Conference (I&CPS), 2015
IEEE Transactions on Industry Applications, 2014
2010 IEEE Conference on Innovative Technologies for an Efficient and Reliable Electricity Supply, 2010
A power plant comprising two 200 kW/230 kVA fuel cells was installed and operated over a period o... more A power plant comprising two 200 kW/230 kVA fuel cells was installed and operated over a period of 15 months. Details of the operating experience and economics of the application are discussed.
IEEE Transactions on Industry Applications, 2000
Industrial and Commercial Power Systems Technical Conference, Annual Meeting, 2012
One of the most common questions in the early stages of designing a new facility is whether the n... more One of the most common questions in the early stages of designing a new facility is whether the normal utility supply to a fire pump is reliable enough to “tap ahead of the main” or whether the fire pump supply is so unreliable that it must have an emergency power source; typically an on-site generator. Apart from the obligation to
Industrial and Commercial Power Systems Technical Conference, Annual Meeting, 2012
One of the most common questions in the early stages of designing a new facility is whether the n... more One of the most common questions in the early stages of designing a new facility is whether the normal utility supply to a fire pump is reliable enough to “tap ahead of the main” or whether the fire pump supply is so unreliable that it must have an emergency power source; typically an on-site generator. Apart from the obligation to
2010 IEEE Conference on Innovative Technologies for an Efficient and Reliable Electricity Supply, 2010
2010 IEEE Conference on Innovative Technologies for an Efficient and Reliable Electricity Supply, 2010
A power plant comprising two 200 kW/230 kVA fuel cells was installed and operated over a period o... more A power plant comprising two 200 kW/230 kVA fuel cells was installed and operated over a period of 15 months. Details of the operating experience and economics of the application are discussed.
2014 IEEE Industry Application Society Annual Meeting, 2014
2010 IEEE Conference on Innovative Technologies for an Efficient and Reliable Electricity Supply, 2010
... operate motors can produce acceptable performance using only 2 current transducers and comput... more ... operate motors can produce acceptable performance using only 2 current transducers and computing the third phase current based upon balanced ... A high speed interactive two step method for detecting island conditions was analyzed and proposed for the power plant. ...