The WindForce Energy with Magnetronic Generator has a significant energy capture advantage over conventional products. Multiple aspects of the WindForce Energy and Magnetronic Generator influence the energy capture advantage. One of the most important aspects contributing to the energy capture advantage is the ability to operate in higher wind speeds. The WindForce Energy has this ability through its flexible yet robust material structure and the Magnetronic Generator has this ability through its proprietary control system related to its discrete coil module control capabilities.
Depending on the wind zone, the benefit of increased cut out speed can improve total energy capture (megawatt hours per year) by a factor of 3 times! (The cut out speed is the speed at which the wind turbine must be shut down to prevent damage to the wind turbine.)
Conventional wind energy systems are engineered primarily for medium wind speed zones. In low wind zones, these systems do not produce sufficient electricity to justify the cost. The cut off speed prevents energy capture at any speed in excess of the cut off speed. In high wind zones, the cut off speed is exceeded a greater percentage of the time vs. low wind zones. In some wind zones, the mean wind speed is near or in excess of the cut off speed, preventing the wind turbine from being used a large percentage of the time and lowering total energy capture vs. available wind energy.
While GE and their competitors publish a cut out speed of much higher values, in practice in the industry the wind farm operators start feathering blades at around 28 mph and shut down the wind turbine by 32-35 mph to prevent damage to the wind turbine. No energy is captured above the cutoff speed.
Even if the efficiency of the above turbine is 100% in normal operation (which it is not), the practical efficiency of the turbine above the cut out speed is 0% because no energy can be captured. In other words, efficiency must be taken into account across the performance curve. Conventional wind turbine manufacturers seem to have adopted the habit of publishing and focusing on peak efficiency. The perspective presented here shows the limitations of focusing solely on peak efficiency as a primary indicator of wind turbine potential. Instead, efficiency vs. wind speed (other useful parameter) is a more useful perspective.
The effects of cut out speed are further evaluated using the NREL (National Renewable Energy Laboratory) Annual Energy Capture Analysis. In the following analysis, two turbines are compared:
The below analyses show the energy capture improvement resulting from the increased cut off speed in a 30 mph average wind speed area. The improvement is 2854 MWH/year to 7824 MWH/year, which is a factor of 3x improvement.
Materials have been one of the Achilles heals of the conventional wind industry. Due to large sizes, the wind industry has sought for lighter, better structural materials for the blade systems. Ultimately, they resorted to carbon fiber blades. Carbon fiber is known to be light and strong. At first glance, it is an ideal material for a turbine blade. Unfortunately, there have been a large number of blade failures due to 1) the inability of carbon fiber to stand vibrations over time, 2) the inability of the blades to resist lightning strikes or withstand fires, and 3) the inability of the blades to prevent the spread of damage from small damaged areas. When carbon fiber fails, it tends to fail catastrophically. Finally, carbon fiber is extremely expensive, difficult to use in manufacturing, and very difficult to repair.
The WindForce Energy is made from a flexible, aerospace urethane. This material does not fail catastrophically, can withstand lightning strikes, is fire retardant, can stand vibrations or significant deformations over an extended period of years, and does not cause propagation of damage from small areas to larger areas to cause catastrophic failures. The WindForce Energy urethane is inexpensive, easy to manufacture (simple injection molding), and can operate for long periods even if damaged. WindForce Energy blades can be manufactured with a very small percentage of upfront capital equipment investment, manufacturing space requirements, and labor requirements as compared to conventional systems.
There are a number of potential structural issues that are easily addressed as the WindForce Energy is scaled up to larger sizes. In the smaller sizes tested, the blades show no significant vibration or flutter. Clearly, the potential for vibration or flutter increases with larger blades. Fortunately, the WindForce Energy has several design parameters that can be readily adjusted to accommodate increased strength for vibration or flutter resistance:
There is ongoing engineering analysis to determine the optimal blade diameters and sizes for various wind zones. As the WindForce Energy is injection molded in a relatively inexpensive and potentially even modular or portable manufacturing system, blade width, thickness, and length are all readily adjustable.
It is envisioned that blade size could be as large as conventional systems if needed; however, a system, which is optimized for a higher wind speed zone, needs to be capable of operating at higher speeds. In such a situation, it may not be appropriate to build large systems but instead to build multiple smaller systems. The WindForce Energy will be optimized and customized for each wind zone. The very simple and economical manufacturing methods used with the WindForce Energy make this a feasible strategy, whereas the manufacturing methodology of conventional systems would make this approach far less feasible.
WindForce Energy blade sizes are projected to be far less expensive to produce than conventional blades of the same size. Therefore, even if the WindForce Energy blades have no size advantage, they still have an economics advantage. It is believed; however, that WindForce Energy blades have at least a 23% size reduction advantage in higher wind zones than conventional systems.
The weight advantage comes from a lighter blade system, a lighter generator system, and no need for a gearbox, as the WindForce Energy and Magnetronic Generator are direct drive. The WindForce Energy and Magnetronic Generator have a small fraction of the total weight of conventional systems. This translates to reduced raw materials, reduced shipping costs, and reduced crane requirements for installation, among other cost reductions.
The WindForce Energy and Magnetronic Generator are both designed to be shipped in standard 20 or 40 foot shipping containers. In fact, using a modular form of the WindForce Energy blade manufacturing process, the blades could even be injected on site if needed for large systems. Most people have at least limited exposure to the very large wind conventional blades being shipped on special oversize load conditions. A less obvious problem with these large conventional shipments is that in many potential wind farm areas roads are not sufficient for these types of shipments. This is not a problem for the WindForce Energy system.
The WindForce Energy and Magnetronic Generator are both designed to be able to be serviced by a standard two man utility crew. Almost no potential failure of the Magnetronic Generator would require that the system be removed from the tower for repair. These repairs can be completed on site, and in most cases, with the system under power. Coil modules can be easily replaced in minutes. Electronics are also modular and easily replaced in minutes. The WindForce Energy has no feathering apparatus, no active wind direction position apparatus, and no gear box, meaning that no service will be required for these non- existent systems.
Since the WindForce Energy and Magnetronic Generator are projected to practically eliminate crane requirements for repairs, the crane cost savings alone are sufficient to completely change the return on investment for the system. In addition, the reduced maintenance will further enhance the ROI.
High operations and maintenance costs and poor reliability lead to reduced financial performance and reduced profit margins on current large wind mill systems. Analysis of this machine reduces maintenance costs from .15/kWh to .005/kWh, a 300% improvement.
GETI has designed its turbine system to reduce operating costs and, where possible, eliminate the complete subsystem failures. These considerations point to a much higher ROI and lower operating costs.
The primary advantages of the WindForce Energy and Magnetronic Generator wind turbine system have been reviewed. These advantages include:
Each of these advantages contributes to overall economic advantages of GETI's product offering. These advantages will translate to profitability (not just higher profitability since typical wind farm owners are actually losing money), to a much higher percentage of uptime, and to a much better ROI for the wind farm owners.