It is possible to install a solar system that is independent of the electrical grid. This is called an off-grid system, and it requires that the solar panels are able to produce enough electricity to cover 100% of the energy needs of the building. Most homes have higher electricity demand in the evening or at night, so off-grid systems usually incorporate either a battery (to store energy produced during the day), a backup source of energy (like a generator), or both. Off-grid systems are more complex and less flexible.
Off-grid systems are most common in remote locations without utility service. Off-grid solar-electric systems operate independently from the local utility grid to provide electricity to a home, building, boat, or RV (or remote agricultural pumps, gates, traffic signs, etc.). These systems typically require either a battery bank (to store solar electricity for use during night time or cloudy weather) a backup source of energy (like a generator), or both. An off-grid solar system must be large enough to produce enough electricity to cover 100% of the energy needs of the buildling. In all off-grid scenarios, electrical usage must be monitored and kept below the maximum output of the panels and batteries as there is no grid-source to supply excess power.
Panels
- PV panels, which cost anywhere from Rs. 35 per watt to over Rs. 50 per watt, are the single biggest expense of a PV system. Their placement and mounting affect your system performance more than any other facet of the job.
Mounting Equipment
- Mounting your PV panels is of critical importance. First, you need to mount the panels where they’ll get maximum sunshine over the course of a year. But the more difficult problem is to mount them with enough integrity that they’ll stay put for 25 years or more.
DC-to-AC inverters
- Inverters take the low-voltage, high-current signals from the PV panels and convert them into 120VAC (or 240 VAC), which is directly compatible with grid power. Inverters cost around Rs. 45 per watt, or around Rs.2,00,000 for a typical application. From a reliability standpoint, they are generally the weak link in any PV system, so quality is a must.
Tracking Mounts
- Tracking mounts mechanically move the PV panels over the course of a day so that they directly face the sun at all times. Dual axis trackers change both azimuth and elevation, while single axis trackers only match the azimuth.
Disconnect Switches
- Disconnect switches are of critical importance, and they need to be mounted within easy reach. Every member of your family should know exactly how to turn the PV system off for safety reasons. If any abnormal behavior occurs in your home’s electrical system, shut off the solar system first.
Wiring and Fuse Box Connections
- Wiring, conduit, and connections to your household main fuse box are minor hardware expenses, but they comprise a big chunk of the labor when you’re installing a PV system.
Battery Bank
- To make system active by provide battery backup when On-Grid solar system is OFF. This backup can be design up to requirement and few hour to 24 hours. This battery bank charge by charger & controller and discharge by inverter provided in this system.