Institutional-Scale Operational Symbiosis Of Photovoltaic And Cogeneration Energy Systems, M. Mostofi, A. H. Nosrat, Joshua M. Pearce
Dec 2010
Institutional-Scale Operational Symbiosis Of Photovoltaic And Cogeneration Energy Systems, M. Mostofi, A. H. Nosrat, Joshua M. Pearce
Joshua M. Pearce
Due to the negative environmental effects of fossil fuel combustion, there is a growing interest in both improved efficiency in energy management and a large-scale transition to renewable energy systems. Using both of these strategies, a large institutional-scale hybrid energy system is proposed here, which incorporates both solar photovoltaic energy conversion to supply renewable energy and cogeneration to improve efficiency. In this case, the photovoltaic reduces the run time for the cogeneration to meet load, particularly in peaking air conditioning times. In turn, however, the cogeneration system is used to provide power back up for the photovoltaic during the night …
Expanding Photovoltaic Penetration With Residential Distributed Generation From Hybrid Solar Photovoltaic Combined Heat And Power Systems, Joshua M. Pearce
Jul 2009
Expanding Photovoltaic Penetration With Residential Distributed Generation From Hybrid Solar Photovoltaic Combined Heat And Power Systems, Joshua M. Pearce
Joshua M. Pearce
The recent development of small scale combined heat and power (CHP) systems has provided the opportunity for in-house power backup of residential-scale photovoltaic (PV) arrays. This paper investigates the potential of deploying a distributed network of PV + CHP hybrid systems in order to increase the PV penetration level in the U.S. The temporal distribution of solar flux, electrical and heating requirements for representative U.S. single family residences were analyzed and the results clearly show that hybridizing CHP with PV can enable additional PV deployment above what is possible with a conventional centralized electric generation system. The technical evolution of …
Thermodynamic Limitations To Nuclear Energy Deployment As A Greenhouse Gas Mitigation Technology, Joshua M. Pearce
Dec 2007
Thermodynamic Limitations To Nuclear Energy Deployment As A Greenhouse Gas Mitigation Technology, Joshua M. Pearce
Joshua M. Pearce
To both replace fossil-fuel-energy use and meet the future energy demands, nuclear energy production would have to increase by 10.5% per year from 2010 to 2050. This large growth rate creates a cannibalistic effect, where nuclear energy must be used to supply the energy for future nuclear power plants. This study showed that the limit of ore grade to offset greenhouse gas emissions is significantly higher than the purely thermodynamic limit set by energy payback times found in the literature. In addition, any use of nuclear energy directly contributes heat to the Earth, which the Earth must radiate into space …
Industrial Symbiosis For Very Large Scale Photovoltaic Manufacturing, Joshua M. Pearce
Jul 2007
Industrial Symbiosis For Very Large Scale Photovoltaic Manufacturing, Joshua M. Pearce
Joshua M. Pearce
In order to stabilize the global climate, the world's governments must make significant commitments to drastically reduce global greenhouse gas (GHG) emissions. One of the most promising methods of curbing GHG emissions is a world transition from fossil fuels to renewable sources of energy. Solar photovoltaic (PV) cells offer a technically sustainable solution to the projected enormous future energy demands. This article explores utilizing industrial symbiosis to obtain economies of scale and increased manufacturing efficiencies for solar PV cells in order for solar electricity to compete economically with fossil fuel-fired electricity. The state of PV manufacturing, the market and the …
Catalyzing Mass Production Of Solar Photovoltaic Cells Using University Driven Green Purchasing, Joshua M. Pearce
Dec 2005
Catalyzing Mass Production Of Solar Photovoltaic Cells Using University Driven Green Purchasing, Joshua M. Pearce
Joshua M. Pearce
Purpose – The purpose of this paper is to explore the use of the purchase power of the higher education system to catalyze the economy of scale necessary to ensure market competitiveness for solar photovoltaic electricity. Design/methodology/approach – The approach used here was to first determine the demand necessary to construct “Solar City factories”, factories that possess equipment and processes sized, dedicated and optimized to produce only solar photovoltaic systems. Inexpensive solar cells from these factories could produce solar electricity at rates comparable to conventional fossil‐fuel derived electricity. Then it was determined if sufficient demand could be guaranteed by green …
Optimization Of Protocrystalline Silicon P-Type Layers For Amorphous Silicon N-I-P Solar Cells, G. M. Ferreira, Chi Chen, R. J. Koval, Joshua M. Pearce, C. R. Wronski, R. W. Collins
May 2004
Optimization Of Protocrystalline Silicon P-Type Layers For Amorphous Silicon N-I-P Solar Cells, G. M. Ferreira, Chi Chen, R. J. Koval, Joshua M. Pearce, C. R. Wronski, R. W. Collins
Joshua M. Pearce
Real time spectroscopic ellipsometry has been applied to develop deposition phase diagrams for p-type hydrogenated silicon (Si:H) films prepared at low temperature (200 °C) by rf plasma-enhanced chemical vapor deposition using gas mixtures of SiH4, H2, and BF3. These diagrams depict the regimes of accumulated thickness and H2-dilution ratio R=[H2]/[SiH4] within which p-type amorphous Si:H [a-Si:H], mixed-phase Si:H [(a + μc)-Si:H], and single-phase microcrystalline Si:H [μc-Si:H] films are obtained in depositions on R=0 a-Si:H surfaces. The performance of n–i–p solar cells incorporating p-layers deposited under the same conditions as those used in the phase diagram development has been correlated with …
Evolution Of Microstructure And Phase In Amorphous, Protocrystalline, And Microcrystalline Silicon Studied By Real Time Spectroscopic Ellipsometry, R. W. Collins, A. S. Ferlauto, G. M. Ferreira, Chi Chen, Joohyun Koh, R. J. Koval, Joshua M. Pearce, C. R. Wronski
Jan 2003
Evolution Of Microstructure And Phase In Amorphous, Protocrystalline, And Microcrystalline Silicon Studied By Real Time Spectroscopic Ellipsometry, R. W. Collins, A. S. Ferlauto, G. M. Ferreira, Chi Chen, Joohyun Koh, R. J. Koval, Joshua M. Pearce, C. R. Wronski
Joshua M. Pearce
Real time spectroscopic ellipsometry has been applied to develop deposition phase diagrams that can guide the fabrication of hydrogenated silicon (Si:H) thin films at low temperatures (<300°C) for highest performance electronic devices such as solar cells. The simplest phase diagrams incorporate a single transition from the amorphous growth regime to the mixed-phase (amorphous+microcrystalline) growth regime versus accumulated film thickness [the a ͢(a+µc) transition]. These phase diagrams have shown that optimization of amorphous silicon (a-Si:H) intrinsic layers by RF plasma-enhanced chemical vapor deposition (PECVD) at low rates is achieved using the maximum possible flow ratio of H₂ to SiH₄ that can …
Maximization Of The Open Circuit Voltage For Hydrogenated Amorphous Silicon N–I–P Solar Cells By Incorporation Of Protocrystalline Silicon P-Type Layers, R. J. Koval, Chi Chen, G. M. Ferreira, A. S. Ferlauto, Joshua M. Pearce, P. I. Rovira, C. R. Wronski, R. W. Collins
Aug 2002
Maximization Of The Open Circuit Voltage For Hydrogenated Amorphous Silicon N–I–P Solar Cells By Incorporation Of Protocrystalline Silicon P-Type Layers, R. J. Koval, Chi Chen, G. M. Ferreira, A. S. Ferlauto, Joshua M. Pearce, P. I. Rovira, C. R. Wronski, R. W. Collins
Joshua M. Pearce
In studies of hydrogenated amorphous silicon(a-Si:H) n–i–psolar cells fabricated by rf plasma-enhanced chemical vapor deposition (PECVD), we have found that the maximum open circuit voltage (Voc) is obtained by incorporating p-type doped Si:H layers that are protocrystalline in nature. Specifically, these optimum p layers are prepared by PECVD in the a-Si:H growth regime using the maximum hydrogen-to-silane flow ratio possible without crossing the thickness-dependent transition into the mixed-phase (amorphous+microcrystalline) growth regime for the ∼200 Å p-layer thickness. The strong dependence of the p-layer phase and solar cell Voc on the underlying i-layer phase also confirms the protocrystalline nature of the …
Photovoltaics — A Path To Sustainable Futures, Joshua M. Pearce
Apr 2002
Photovoltaics — A Path To Sustainable Futures, Joshua M. Pearce
Joshua M. Pearce
As both population and energy use per capita increase, modern society is approaching physical limits to its continued fossil fuel consumption. The immediate limits are set by the planet’s ability to adapt to a changing atmospheric chemical composition, not the availability of resources. In order for a future society to be sustainable while operating at or above our current standard of living a shift away from carbon based energy sources must occur. An overview of the current state of active solar (photovoltaic, PV) energy technology is provided here to outline a partial solution for the environmental problems caused by accelerating …
The Use Of Self-Directed Learning To Promote Active Citizenship In Science, Technology, And Society Classes, Joshua M. Pearce
Jul 2001
The Use Of Self-Directed Learning To Promote Active Citizenship In Science, Technology, And Society Classes, Joshua M. Pearce
Joshua M. Pearce
The purpose of this article is to outline the viability of a student-directed assignment within collegiate-level STS curricula for the improvement of the utilization of scientific knowledge and technology in society. The assignment, christened the Do Something! assignment, is a novel teaching tool that utilizes students’ individual interests to encourage in-depth learning across disciplines and capitalizes on their personal skills and talents to solve real-world problems. The Do Something! assignment has been utilized in two STS courses at The Pennsylvania State University (STS 100: The Ascent of Humanity and STS 200: Critical Issues in STS). The structure of this assignment …
