Rooftop solar PV systems consist of solar PV panels and balance of system, which comprises transformers, electricity systems, and monitoring and mounting equipment along with mounting and installing modules. Rooftop solar PV systems are increasingly getting popular as they provide off-grid and on-grid flexibility. The use of rooftop solar PV demand is spreading quickly in the emerging markets, the policy environment is providing optimal opportunity in the developed and developing geographies. The continuing growth and geographical expansion of solar PV demand has driven decline in solar modules prices globally, this further assisted in the capacity additions of solar PV additions. Rise in demand for renewable energy and the electricity generation adding the growth in the global solar PV market.
Rooftop solar systems can be installed at various locations, such as household and commercial building rooftops and above parking spaces, using balance of system including inverters, transformers, wiring, and monitoring equipment, making them a convenient option. The Energy Payback Time (EPBT) for 2 kWp rooftop solar systems is around two to three years, thus making these systems an economically viable and efficient alternative. Distributed PVs (DPVs) with a capacity of less than 100 kW are preferred for rooftop solar systems. However, as the difficulties with FIT persist for DPV, solar leasing has gained popularity and is expected to boost the rooftop solar market. Rooftop solar continues to depend on different incentive mechanisms that drive the demand such as technology-specific renewable portfolio standards (RPS) and tenders, tax credits, traditional feed-in tariffs or Power Purchase Agreements (PPAs), as well as premiums for the feed-in of excess power generated in self-consumption systems.
Rooftop solar systems are more suitable for self-consumption, i.e. electricity should be used at the site where it is generated. Transmission of solar electricity to other sites is less efficient for rooftop solar due to lack of smart grid infrastructure. Electricity trading is done for a limited amount of electricity due to the absence of infrastructure. Although net metering has been implemented in almost all the major rooftop solar markets. Net metering has attracted negative attention from other utilities, including fossil fuel utilities. Overall impact of these factors affects the implementation and adoption of rooftop solar systems and renders the market volatile. The situation for connecting new installations to the grid is very alarming. Customers in different geographies are struggling to understand solar commitment and targets by each government globally.