The rooftop plants are conventionally divided into two parts: the solar PV (solar panels) and hardware components, which includes inverters, racking and installation hardware. Solar PV does not have any mechanical or serviceable parts, so solar panels have a useful life up to 40 years or more. Most of solar manufacturers sell their products with 25 years warranty in India. This warranty covers 80% efficiency up to 25 years. There will be a slight change in efficiency of the panel after span of warranty period.