NEC Rules on Alternative Energy Systems — Part 2

SIDEBAR: Where the Wind Blows

Conversion of wind power to electricity is not new. This concept was used in rural farming areas prior to the Rural Electrification Act of 1936, which brought rural electrical cooperatives into existence. Installing and maintaining a battery system remains one of the barriers to wide-spread use of wind power. As a result, the stand-alone small wind electric system is not seen as commonly as interconnected systems to supplement the electric utility power supply.

Most of the wind generation installation work is for large-scale wind farms. Wind farms consist of wind turbines too large to be covered by Art. 694. The types of installations that fall under Art. 694 are typically for a specific building or facility. They can serve as the sole supply for a structure, but more commonly serve as a supply in addition to other sources [694.7(A)]. The scope of Art. 694 limits it to one or more wind electric generators with individual generators having a rated power up to and including 100kW [694.1].