Advantages and challenges of solar PV

Solar photovoltaic (PV) technology converts sunlight directly into electricity using semiconductor cells.

Advantages

• Free, abundant and renewable fuel; no fuel transport.
• No emissions, noise or moving parts during operation; low maintenance.
• Modular and scalable: from a watch to a MW plant; installed on rooftops with no extra land.
• Long life (25 years or more) and falling cost (the price of modules has dropped by about 90% in a decade).
• Ideal for remote areas without grid; solar home systems in Nepal.
• Peak output coincides with daytime load (and with dry season irrigation and cooling demand).
• Creates local jobs, reduces fuel imports.

Disadvantages

• Output only in daytime and depends on weather; intermittent.
• Low efficiency of cells (15–22%) so large area is needed.
• High initial cost, especially with batteries.
• Needs storage (batteries) and inverters, which have a shorter life (5–15 years).
• Performance falls with high temperature and dust.
• Manufacturing uses energy and some toxic materials; end-of-life panel waste.

Challenges

• Storage and grid integration: managing variable output; in Nepal, NEA can use flexible (storage and peaking) hydropower to balance solar output.
• Financing and cost of batteries for the rural poor.
• Import dependence: Nepal imports almost all of its panels, inverters and batteries.
• Technical skills, standards and quality control; counterfeit and low-quality products.
• Land use for large plants, and recycling of used panels and batteries.
• Policy and net metering rules for rooftop systems. Despite these, PV is one of the fastest-growing sources worldwide.