Abstract: Wind turbine farms are presented including: a number of steerable wind turbines, where each of the number of steerable wind turbines includes a turbine diameter, where each of the number of steerable wind turbines are steerable about a vertical axis, where each of the number of steerable wind turbines includes a wake centerline, where the number of steerable wind turbines is grouped, where each group is defined by at least two steerable wind turbines, where each of the number of steerable wind turbines is positioned in a fixed position such that wake centerlines are separated by approximately 0.5 and 6.0 turbine diameters.

Abstract: Wind turbine farms are presented including: a number of steerable wind turbines each having a turbine diameter, where the number of steerable wind turbines is grouped pairwise into a number of monopole wind tower pairs, where each monopole wind tower pair is placed in a fixed pair placement and oriented in one of a number of fixed pair orientations, where each one of the number of fixed pair orientations corresponds with one of a number of prevailing wind directions, and where the number of monopole wind tower pairs is placed in a number of fixed pair positions.

Abstract: Wind turbine farms are presented including: a number of steerable wind turbines each having a turbine diameter, where the number of steerable wind turbines is grouped pairwise into a number of monopole wind tower pairs, where each monopole wind tower pair is placed in a fixed pair placement and oriented in one of a number of fixed pair orientations, where each one of the number of fixed pair orientations corresponds with one of a number of prevailing wind directions, and where the number of monopole wind tower pairs is placed in a number of fixed pair positions.

Abstract: Wind turbine farms are presented including: a number of steerable wind turbines each having a turbine diameter, where the number of steerable wind turbines is separated into a number of modules each placed in a fixed module placement and oriented in one of a number of fixed module orientations, where each one of the number of fixed module orientations corresponds with one of a number of prevailing wind directions, where the number of modules is separated into a number of sets placed in a number of fixed set positions. In some embodiments, each of the number of modules is positioned no closer than approximately six turbine diameters and no further than approximately fifteen turbine diameters from each another.

Abstract: Wind turbine farms are presented including: a number of steerable wind turbines each having a turbine diameter, where the number of steerable wind turbines is separated into a number of modules each placed in a fixed module placement and oriented in one of a number of fixed module orientations, where each one of the number of fixed module orientations corresponds with one of a number of prevailing wind directions, where the number of modules is separated into a number of sets placed in a number of fixed set positions. In some embodiments, each of the number of modules is positioned no closer than approximately six turbine diameters and no further than approximately fifteen turbine diameters from each another.

Abstract: The invention includes method and apparatus for controlling the stability of a burner, preferably a low NOx burner, of a natural draft heater. The method includes measuring the draft over a time period and generating a measured output from which a draft function is determined that defines the relationship between the draft and time during the time period. A value for the burner stability is defined that is representative of a stable burner operation. The draft function is compared to the stable burner value to determine a differential value, and the operation of the fired heater is adjusted in response to the differential value. The apparatus includes means for measuring the draft over a time period and means for generating a measured output from which a draft function is determined that is proportional to the cyclic variation of the draft during the time period.