P.R. Diefenderfer, E.R. Prescott and P.M. Jansson, “Peak and Energy Contributions of Distributed PV to PJM,”  4^th International Conference on Renewable Energy Research and Applications (ICRERA 2015), Palermo, Italy, 22-25 November 2015, IEEE Xplore Digital Object Identifier: 10.1109/ICRERA.2015.7418611, pp. 1265-1268

Abstract

C. Barreiro, A. Bross, J.L. Schmalzel and P.M. Jansson, “Sensor Array for PV Shading Measurements,” Proceedings of the IEEE Sensors 2011 Conference, Limerick, Ireland, 28-31 October 2011, IEEE Xplore Digital Object Identifier: 10.1109 / ICSENS.2011.6127368, pp. 1889-1892

Abstract
The number of photovoltaic (PV) system installations around the world is rapidly expanding, driven by a combination of factors including steadily falling costs, tax and rebate incentives, and interest in carbon reduction. Optimizing the total energy production of PV systems is dependent on minimizing losses and avoiding conditions which can adversely affect performance and lifetime. Module shading is one such critical element. Shading can arise from inter-row effects as well as from vegetation, buildings, and precipitation. In order to make objective measurements of shading, we have designed a system employing spot metering and sensor arrays. In order to bring array monitoring costs to affordable levels, we have employed low-cost photodiodes that are deployed in the mobile and computer market. Our shading sensor is organized in a linear array. This paper describes the development and characterization of the sensor array and provides examples of its use to evaluate the effects of inter-row shading that could be experienced by a typical PV module.

P.M. Jansson, K. Whitten, J.L. Schmalzel, “Photovoltaic Module Shading: Smart Grid Impacts,” Proceedings of the 2011 IEEE Sensors Applications Symposium, San Antonio, Texas, 22-24 February 2011, IEEE Xplore Digital Object Identifier: 10.1109 / SAS.2011.5739826, pp. 323-328

Abstract
In the design of a solar photovoltaic system, one criterion that continues to receive low priority is the provision of minimum inter row spacing for photovoltaic modules. Consumers and installers alike strive to maximize area usage for systems such that they achieve the highest amount of annual energy output. This, in turn, leads to module rows being designed very close to each other; with array tilt lowered in an attempt to reduce inter row shading. This design practice fails to take into consideration many effects that close row spacing can have on system output. When designing a photovoltaic array to optimize its performance as a power generator and its contribution to the electric grid during peak demand periods – shading concerns become a key consideration. This paper describes a process developed at Rowan University’s Center for Sustainable Design to test the impact that inter row shading can have on power output and performance across the day. A test rig and protocol were created which tested module’s output given various depths of shading from one row of modules upon another. The exclusion of bypass diodes in the system was also tested to view the most extreme possible cases of power loss induced by shading. The results of this experimentation showed that even very small amounts of shading upon solar photovoltaic modules can lead to significant loss in power generation. As more PV systems are installed on the utility system their availability during peak times becomes an ever increasing requirement for Smart Grid success. This paper also explores the ramifications that proper inter row spacing design guidelines could have on reinforcing some of the fundamental principles of Smart Grid.

 K. Whitten, P.M. Jansson, P. Gorgas and P. Castro, “The Implementation of Climate Neutrality Initiatives on University Campus: Large Scale Photovoltaic Project,” International Journal on Environmental, Cultural, Economic and Social Sustainability, (Spring 2011) Volume 7, Issue 2, pp. 51-72

Abstract
Rowan University is a public institution of higher education in the State of New Jersey in the United States (US). The first institution to commit to climate neutrality in the state is now undertaking its first major capital project (over $40M USD) designed to bring its climate footprint towards its ultimate goal of zero by installing a 10-MW grid connected photovoltaic system (to be the 8th largest PV system in the US.) Using a public private partnership and a power purchase agreement the university will begin its major sustainability initiatives without spending any of its own capital resources. This first step is funded by a third party capable of taking advantage of federal tax incentives that this nonprofit institution is not eligible for. Buying the system back in the future will enable the University to achieve reductions in its climate footprint now, achieve immediate energy savings and embark on cutting edge research and development at its South Jersey Technology Park location. This model is useful to other industries and organizations seeking to become sustainable at low or no cost. This paper describes the many benefits of the project and its role in the university’s quest for sustainability as a campus.

U. Schwabe and P.M. Jansson, “Utility-Interconnected Photovoltaic Systems Reaching Grid Parity in New Jersey,” Proceedings of the IEEE Power and Energy Society General Meeting, Minneapolis, Minnesota, 25-29 July 2010, IEEE Xplore Digital Object Identifier: 10.1109 / PES.2010.558968 , pp. 1-5

O. Sikder, C. Torres and P.M. Jansson, “Comparative Analysis of Energy Storage for Photovoltaics: Electrical vs Virtual,” 47th Annual National Conference and Summit of the American Solar Energy Society (ASES), August 5-8, 2018, Boulder, Colorado

Abstract
The recent successful deployment of 100+ MWhrbattery in South Australia by Tesla to solve grid problems with the intermittent generation of renewables places an economic stake in the ground for energy storage. Virtual energy storage at the Bucknell University Residential Microgrid testbed has demonstrated that multiple kWhrs of electricity can be successfully shifted during utility heating and cooling peaks at a fraction of the cost of batteries. While load management and pre-cooling and pre-heating of residential dwellings have been discussed historically as potential solutions to intermittent generation from photovoltaics(PV), our work in a live test bed definitively demonstrates that load shifting can be the electrical equivalent of battery energy storage while maintaining occupant comfort and satisfaction. It is our hope to reinvigorate the discussion about these options because they are not only more economic than physical electrochemical batteries but they represent a much more sustainable pathway to meet utility near term electricity storage needs.

P.M. Jansson, “Net Metering PV Distributed Resources Benefits All Stakeholders on PJM,” Solar 2016 / INTERSOLAR 2016, the American Solar Energy Society, San Francisco, California, 11-13 July 2016

Abstract
This research documents that all stakeholders (utilities, shareholders, customers –participants and non-participants, society, etc.) benefit from the electric utility policy of net metering of photovoltaics at the distribution level on PJM. It is important to share this objective data given the current political activity across the nation which inaccurately represents that the net-metering policy is somehow harmful to the utility and its customers. The papers finding to the contrary is based upon analysis of real data from locational marginal pricing across the RTO and at specific nodes within it. While one would expect that power generated during the day for a summer peaking utility is of more value to the electric utility system (since demands tend to be relatively higher at that time) this research documents the difference in PV generation LMP to non-generation LMP on a daily, seasonal and annual basis. Further, the value of photovoltaic capacity is not zero since very often PV systems make a significant contribution at the time of the PJM summer utility system peaks. This paperevolves from multiple other research studies which analyzed similar capacity and energy values coincident with PV generation over the past decade but uses the most recent data available which is affected by lower energy and capacity values in general due to the economic downturn. Apart from the obvious benefits that utility customers accrue by being able to use the grid as virtual storage via the net-metering policy this paper looks at the nearest neighbor impact, the distribution feeder impact, capacity planning requirements, the utility system as a whole, the ISO/RTO, as well as all other ratepayers. In all categories net-metering provides positive benefits to all these stakeholders and at present poses no significant burdens or costs onto the utility system or other ratepayers. The research finds that, in fact, PV system owners provide a positive economic value to the grid for which they are presently inadequately compensated. It is clear that electric utility regulators in 42states, D.C. and multiple territoriesare aware of this positive benefit accruing to all electric utility stakeholders since they continue to support net metering as an important public policy support for solar technology. This research provides important objective economic assessment data that they can use to defend their current policies.

P.M. Jansson, C. Barreiro and J.L. Schmalzel, “Architecture of a Smart Photovoltaic Module,” Proceedings of the 38th IEEE Photovoltaic Specialists Conference, Austin, TX, 3-8 June 2012

Abstract
The U.S. Department of Energy (DoE) mandates that each state prepare an energy assurance plan (EAP) which consolidates energy utilization snapshots for the state along with procedures and strategies to be employed to address a wide range of potential energy emergencies.RowanUniversity was contracted by the State of New Jerseyto develop an EAP. In the spring of 2011 a multidisciplinary team of student engineers was formed as part of a project-based course to begin the EAP development. The result of the semester effort was a compilation of other existing state EAPs, an outline for the new document and initial development of portions of the EAP. During the summer of 2011 fourteen student engineers were hired to continue working on the EAP and the related energy monitoring systems. A significant portion of a draft EAP for the State of New Jerseywas completed at that time. The following two semesters (Autumn 2011 and Spring 2012) had smaller engineering clinic teams continuing to refine the document. It was completed and shared with the State over the summer of 2012 by summer students and their professors when the document went through its final revisions.This paper reports ongeneral aspects of the EAP in order to provide the context and then focuses on the important relationship between project-based coursework and student employment opportunities. Some of the challenges in the academic environment include the sometimes competing goals of (1) providing relevant projects based upon real industry need, and (2) the accompanying expectations of professional deliverables, which are often well beyond the scope of a one-or two-semester project. Projects that provide sufficient funding for students (undergraduate and graduate) offer the best way to provide the sophisticated results that many sponsors expect. Having students continue the momentum developed in the in their class project-based learning experience often results in a corresponding step increase in their productivity when the summer project begins. The EAP team accomplished a significant amount of work as measured by the number of chapters, appendices and references completed, and the responses of the sponsor during regular project reviews.This approach to the key project-based portion of our curriculum has become a model for how solicit and scope projects from outside sponsors. The paper will address other strengths and weaknesses of the approach.

J. Roche, P.M. Jansson, S. Turner, J .L. Schmalzel, C. Barreiro, “Grid-Connected Photovoltaic System Parity With PJM Generation,” 2011 CleanTech Conference, Boston, Massachusetts, 13-16 June 2011

Abstract
This research provides compelling economic and technical analysis of photovoltaic (PV) system performance in New Jersey and contrasts the generation availability marginal pricing on the world’s largest regional transmission organization (PJM). This analysis indicates that PV generation concurrence with high PJM system locational marginal prices (LMP) reveals values approaching the commensurate life cycle costs of PV without local subsidies. The study provides analysis from three years 2008, 2009 and 2010 showing LMP market values for PV generation located at the South Jersey Technology Park ranging from 15-20 cents per kWh. It is LMP pricing that determines the value of all generation operating at that given hour on PJM. This data indicates that life cycle cost PV generation is of similar magnitudes during the summer periods and with recent reductions in module pricing and commensurate installed PV system cost, these values will reach parity on an annual basis in the near term.

C. Barreiro, P. Jansson, A. Thompson and J. Schmalzel, “PV By-Pass Diode Performance in Landscape vs. Portrait Modalities,” Proceedings of the 37th IEEE Photovoltaic Specialists Conference, Seattle, Washington, 19-24 June 2011

Abstract
By-pass diodes are frequently used to minimize the effects of shading on PV module power generation. However, the functionality and effectiveness of these diodes depends on proper installation of a module with respect to potential shade sources. The lack of general manufacturer guidelines for proper module installation paired with the current level of technical knowledge held by many general contracting firms, may often lead to compromises in the electrical output of a photovoltaic system. The current produced by a single PV cell is directly proportional to the amount of solar irradiation that it is exposed to. However, in power modules many cells are wired in series allowing current flows to be limited by the most shaded cell. Testing of various module types with and without bypass diodes were performed in accordance with the experimental protocols developed at Rowan University’s Center for Sustainable Design (CSD). I-V curves were obtained for a wide range of load impedances using a digital electronic load for both portrait and landscape modalities. Multiple test runs were performed at each shading increment for a single row of cells and the average I-V curve was calculated. Cell row shading was varied from 0-100% in 20 percent increments of cell row height. The study was conducted on multiple modules, covering the primary manufacturing types including: mono-crystalline, poly-crystalline and amorphous silicon. The results of this experimentation showed that the performance efficiency and functionality of by-pass diodes is highly dependent on the orientation of the PV modules. The circuital configuration of PV modules must be taken into consideration when designing a PV array. Depending on the orientation, bypass diodes can be rendered completely ineffective to the point that single cell row shading can reduce power output of the module by as much as 92% and also result in permanent damage to the PV modules.