Photovoltaic system and is typically less useful than a calculation of return on investment. While it is typically calculated to be between 10 and 20 years, the financial payback period can be far shorter with incentives. Due to the low voltage of an individual solar cell (typically ca. 0.5V), several cells are wired "(also see copper used in PV systems)" in series in the manufacture of a "laminate". The laminate is assembled into a protective weatherproof enclosure, thus making a photovoltaic module or solar panel. Modules may then be strung together into a photovoltaic array. In 2012, solar panels available for consumers
Galois module of "v" to "L", let "I" denote its inertia group. A Galois module ρ : "G" → Aut("V") is said to be unramified if ρ("I") = {1}. In classical algebraic number theory, let "L" be a Galois extension of a field "K", and let "G" be the corresponding Galois group. Then the ring "O" of algebraic integers of "L" can be considered as an "O"["G"]-module, and one can ask what its structure is. This is an arithmetic question, in that by the normal basis theorem one knows that "L" is a free "K"["G"]-module of rank 1. If the same is