1. Solar Schoolhouse and San Mateo College Designing and Installing Solar Electric Systems Types of Solar Electric Systems For Technology Teachers San Mateo College May 17, 2008

2. Disclaimer This workshop does not certify you and Solar Schoolhouse and San Mateo College are not responsible for anything you do with this knowledge

3. Three Basic Types: Stand Alone Simple Grid Tied Grid Tie with Battery

4. Grid Tie Solar Electric Systems Quick View

5. Simple Grid-tie system (Utility intertie) Solar Array Inverter Distribution Panel Utility

6. Attaching Rack System To The Roof Mounting bracket bolted into rafter; rack then bolted to mount.

8. Series Wiring with MC Connectors

11. Conduit From Array to Disconnects

12. Simple Grid Tie with Two Inverters: Disconnects, Inverters, and Subpanel To PGE Disconnect And to Meter

13. Subpanel Solar AC in from Inverter Lightning surge arrestor AC from inverter to PG&E disconnect then back to breakers

16. Stand Alone Systems I.e. No Grid

17. SIMPLE: Load directly powered by solar photovoltaic module

18. With Storage: Solar Module Battery Load

19. Stand Alone Residential System Solar Array Charge Controller Battery DC to AC Inverter Distribution Panel AC Distribution Panel DC

20. Small Stand Alone System (to power an office) Solar Array Charge Control Storage: Battery Fuel Gauge Inverter DC to AC

21. Roof mount Solar Array: 4 SM55 220 Watts wired in parallel

22. Stand Alone System Components

24. Disconnect Between Solar Panel and the Battery (via Charge Control) Breakers and fuses must be DC rated. Can purchase special for PV application equipment. In this system we used Square D QO which is ok for DC up to 24 volts

25. Charge Control for Battery: note display and battery type selector

26. Storage: Battery: Flooded, Sealed, AGM, or Gel

27. Fuse: Circuit Protection Must be large enough to allow maximum designed current (+ x%) to flow through circuit and blow before wire overheats (maximum size determined by ampacity rating of wire).

28. Inverter: DC to AC Pure sine wave: T urns DC electricity of PVs and Batteries into AC current. DC in AC out

29. Wire Strategy Select wire sizes that minimize Voltage Drop: based on distance and current Select insulation types depending on where wire is located and whether or not it is in conduit. (UV, temperature, moisture) Be strategic in which voltage you use for system: depends on wattage and length of wire runs

30. Balance of System Inverter Charge Control Fuel Gauge Battery

31. Safety at Schools, etc Follow good wiring practice: keep unshielded wire out of the reach of people: in conduit, behind transparent barrier such as glass or lexan. Fusing, breakers, ground fault protection. DC lines must use DC rated equipment. Batteries must be inaccessible to unauthorized people…i.e. locked Use Adequate Mounts for Solar Panel

32. Larger Stand Alone Systems: 1 kw

33. Combiner Box

34. MX60 Charge Controller in Action

36. Grid Tie with Stand Alone Capability Solar Array Inverter Distribution Panel Charge Control Battery Utility