GULF STREAM ENERGY COMPARED TO WIND

No Wind Power Potential in Southeastern States

Although wind turbines can produce electricity without burning polluting fossil fuels, there is virtually no wind-power potential in the Southeastern States. The National Renewable Energy Laboratory has gathered data on a region-by-region basis to identify the nation’s wind-energy resource. The results of this effort are contained in the Wind Energy Resource Atlas of the United States. The Southeast region consists of Alabama, Florida, Georgia, Mississippi, and South Carolina. The report states, “There is little wind energy potential in the Southeast region for existing wind turbine applications (Zabransky et al. 1981). Even along coastal areas, existing data from exposed sites indicate at best only class 2 at 50 m (164 ft) above ground. The only places in the Southeast region estimated to have class 3 or higher annual average wind resource are the exposed ridge crests and mountain summits confined to northeastern Georgia and extreme northwestern South Carolina.”

The following map is from the National Wind Technology Center. The average wind speeds for specific locations was used to calculate the average annual wind energy in terms of watts per square meter of a turbine’s sweep area. Geographic areas as small as one square mile were assigned a wind power class from 1 to 7. Those areas that have a wind power class of 3 or higher are considered to be candidates for the development of wind farms. The National Wind Technology Center states that utility-scale wind turbines can produce electricity for 4 cents per kilowatt-hour on class 6 wind sites that have average wind speeds of 16 miles per hour at a height of 33 feet. The Southeastern states are not colored because they have a wind power class of 1 and, therefore, no wind generating potential. Although the Southeastern states have no winds to generate power – they do have an ocean current that can generate a steady supply of very cheap electricity.

Gulf Stream Turbines Can Have Much Higher Capacity Factors

Although the wind powered generating systems should be encouraged, they do have a problem in that their source of energy is inherently intermittent. The winds are unpredictable and can fluctuate hourly and have marked seasonal and diurnal patterns. The wind turbines can make good use of their rated power only when the wind velocities are within a relatively narrow range. Because the kinetic energy both increases and decreases with the cube of the wind’s velocity, as the wind speed falls below the turbine’s rated speed, the output drops off sharply.

Those turbines powering asynchronous generators that are directly connected to the grid must spin above minimum speeds to produce usable electricity having the AC frequency in sync with the grid system. Below those rotation speeds most electronic wind turbine controllers are programmed to let the turbine run idle without grid connections. In contrast, the Gulf Stream Turbines will be powered by a current having a much more consistent flow rate that will permit them to produce usable electricity virtually one hundred percent of the time.

Because the winds do not blow steadily at even the best wind sites, the electric power that the wind turbines can produce over time is much less than their rated capacities. This is known in the electricity trade as a low capacity factor. Wind turbines also frequently produce the most power when the demand for that power is at its lowest. Low capacity factors and still lower dependable on-peak capacity factors are the major source of the wind power’s problem. For example, in California, wind power operated at only 23 percent realized average capacity in 1994. That compares with nuclear plants, with capacity factors of about a 75 percent; coal plants, with capacity factors of between 75 and 85 percent, and gas-fired combined-cycle plants, with capacity factors of about 95 percent of their average designed capacity. Depending on where the water turbines are placed, they can operate with capacity factors equal to those of many fossil-fuel plants. Although there will be some changes in the current’s velocity, caused by the moon’s tidal effects and the steadiness of the trade winds, the only renewable energy source having higher capacity factors than well-placed Gulf Stream Turbines would be those existing hydroelectric plants at those dams that have sufficient water in their reservoirs.

Capacity factors are extremely important to the efficiencies and economics of both wind and water-powered generating systems. Let’s assume that a giant wind turbine has a “rated wind speed” of 25 mph and a rated output capacity of 2,316 kilowatts per hour. Multiplying that hourly output capacity by the 8,760 hours in a year gives a theoretical capacity of 20,288,160 kilowatt-hours per year. But because the capacity factors for wind turbines are between 23 and 30 percent, the actual output of the machine would only be between 4,666,277 and 6,086,448 kilowatt-hours per year.

Because the Gulf Stream is driven by our planet’s spinning on its axis and the steady trade winds, its flow rate off of South Florida is nearly constant. Properly placed water turbines having the same rated capacity as the aforementioned wind machines should have capacity factors of between 75 and 95 percent. Because of these much higher capacity factors, the actual output for the Gulf Stream Turbine, having the same rated capacity, should be between 14,201,702 and 19,273,752 kilowatt-hours per year – or about three times more than that produced by the wind turbines in the nation’s best locations. And, as previously stated, there are no potential wind sites in our southeastern states. If any wind turbines were to be placed in Florida, their capacity factors would be near zero.

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