Battery lifespan depends on the technology and maintenance. Lithium-ion batteries last 10-15 years with 5000+ charge cycles, while tubular lead-acid batteries last 5-7 years with proper maintenance. Regular maintenance, avoiding deep discharge below 50%, proper charging practices, and temperature control significantly extend battery life.

Yes, properly sized off-grid systems with adequate inverter capacity can run air conditioners, refrigerators, washing machines, water pumps, and other heavy appliances. The inverter must have sufficient surge capacity (typically 3x rated power) to handle motor startup currents. Battery bank capacity should be sized for extended backup during cloudy weather.

Off-grid systems are designed with 2-3 days of battery autonomy to handle cloudy weather. During extended monsoon periods, solar panels still generate 20-40% of their rated capacity from diffused sunlight. For critical applications, backup diesel/petrol generators can be integrated to charge batteries during prolonged low-sunlight periods.

Off-grid solar is excellent for agricultural irrigation where grid connection is unavailable or unreliable. Since pumps primarily operate during daytime when solar generation is maximum, battery requirements are minimal. Farmers benefit from zero electricity costs, reliable daytime operation, and MNRE subsidies for solar agricultural pumps.

Regular maintenance includes monthly battery water level checks (for flooded lead-acid), quarterly solar panel cleaning, semi-annual terminal tightening and corrosion checks, and annual professional inspection. Lithium batteries are maintenance-free. Monitoring battery voltage, charging status, and keeping terminals clean ensures optimal performance and longevity.

Yes, off-grid systems are modular and can be expanded by adding more solar panels and battery capacity. However, ensure initial design accommodates expansion with properly sized charge controller and inverter. Battery expansion requires matching voltage, capacity, and age of existing batteries for optimal performance.