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
Module (mathematics) to zero by "f". The isomorphism theorems familiar from groups and vector spaces are also valid for "R"-modules. The left "R"-modules, together with their module homomorphisms, form a category, written as "R"-Mod (see category of modules for more.) This is an abelian category. Finitely generated. An "R"-module "M" is finitely generated if there exist finitely many elements "x", ..., "x" in "M" such that every element of "M" is a linear combination of those elements with coefficients from the ring "R". Cyclic. A module is called a cyclic module if it is generated by one element. Free. A free "R"-module