ELTR 1223 Survey of Renewable Energy Technology PV Power System Sizing and Configuration Unit 7 Source: Use Policy This material was developed by Timothy J. Wilhelm, P.E., Kankakee Community College, with funding from the National Science Foundation as part of ATE Grant No. 0802786. All materials in this presentation are designed and intended for educational use, only. They may not be used for any publication or commercial purposes. Source: Author, Editors/Reviewers Author: Timothy J. Wilhelm, P.E., Kankakee Community College Editors/Reviewers / Modifier: Chris Miller Heartland Community College Source: Objectives Students will be able to describe, in very simple terms, at least three differences ( hardware differences and/or operational differences) between a pure grid-tied solar-PV system and a stand-alone solar-PV system. Students will be able to list, and briefly describe (in very simple terms), the basic steps for sizing a stand-alone solar-PV power system. Source: Objectives Students will be able to describe, in very simple terms, the general construction of a pure gridtied solar-PV power system, listing its basic components. Students will be able to describe, in very simple terms, electric motor effect and electric generator effect. Source: Objectives Students will be able to describe, in very simple terms, how motor effect creates back-torque in an electric generator. Source: Simple Utility-Tied System Source: http://www.rhoduselectric.com/images/10-14-08/Solar_Electric_Systems.jpg Utility-Tied PV System is very simple, with few components. System is sized almost strictly by budget. “How much can you afford to buy?” System is modular and expandable in building-blockincrements. System does NOT provide back-up power when utility shuts down. Can be configured to provide back-up power; but, involves additional equipment and more expense. PV voltage approaches 600VDC! Utility-Tied PV Parts and Pieces PV Modules and interconnect wiring. Racks for mounting PV array. Combiner boxes for parallel connection of series strings of PV modules. GFP for roof-mounted, residential arrays. Grid-tie inverter. Lockable, outside disconnect. Properly sized bi-directional breaker in distribution panel. PV Modules PV Module Interconnects Source: http://www.mrsolar.com/Merchant2/graphics/produc t/wiring/blue_unconnected.jpeg PV Mounting Racks Ballasted Pans for Flat Roof PV Mounting Racks Fixed Racks for Pitched Roof PV Mounting Racks Fixed Racks for Pitched Roof PV Mounting Racks Fixed Racks for Pitched Roof PV String Combiner Box Grid-Tie Inverters Source: http://www.altestore.com/store/descfiles/xantrex/in verters/gt3/Xantrex_grid_tie.jpg Source: http://hitechplumbingcorp.com/sitebuilder/images/S MA3000_Prod_sb3000us_md_20070727112949167x174.jpg Grid-Tie Inverters, Lockable AC Disconnect Inverter Output to Main Panel Lockable Disconnect! Simple Stand-Alone System Source: http://homepower.com/images/basics/Basics_SolarElect_OffGridFlow.jpg Stand-Alone PV System is more complex and more expensive than pure grid-tie. System is sized by load analysis. System is modular and expandable in building-blockincrements. System IS back-up power when utility not available. Requires monitoring and battery maintenance. You must operate within your ENERGY budget. PV voltage typically 12VDC, 24VDC or 48VDC, nominal. Stand-Alone PV -- Parts and Pieces PV Modules and interconnect wiring. Racks for mounting PV array. Combiner boxes for parallel connection of series strings of PV modules. GFP for roof-mounted, residential arrays. PV Charge Controllers. Batteries. Inverter/Charger. Load Center. Disconnects and OCP, everywhere. PV Charge Controllers Source: http://www.exploroz.com/images/Articles/ 349_Image1__TN180x200.jpg?6996 Source: http://www.readymaderesources.com/cart /images/uploads/xw60-150.jpg Source: http://www.enviroharvest.ca/images/O utbackmx60Controller.gif Batteries Lead Acid Cells are Standard Flooded cell Gel Cell SMF AGM SMF Batteries Source: http://shop.solardirect.com/ima ges/pv-concorde-battery-d.gif Source: http://www.electric-cars-arefor-girls.com/images/6-volt-golf-cartbattery-Trojan-T-105.jpg Source: http://suntolight.com/imagenes/productos/S24SLD.jpg Inverter/Chargers Source: http://www.alternativeenergydiscounthouse.c om/images/products/VFX3648.jpg Source: http://www.msmelectric.com/mediac/400_0/media/Xantrex_SW.JPG Put the pieces together… Source: http://img.diytrade.com/cdimg/476964/2901505/0/1162516202.jpg Sizing a Stand-Alone System See In-Class Worksheet Do you have proper solar access? Do your load analysis. Size your battery – days of autonomy. Size your PV array – recharge in a day (or two, max.) Size system for worst-case conditions! Grid-Tied with Batteries Source: http://homepower.com/images/basics/Basics_SolarElect_GridBBFlow.jpg Final Notes Illinois now has mandatory net-metering! If you have utility available, USE IT! 30% investment tax credit for next 8 years! 50% grants/rebates available from State (maybe)! Production tax credit? Let the Sun Shine!