A company in Montana, Terra Moya Aqua, has a new vertical-axis wind turbine that is said to produce energy at 43-45% efficiency, and costs only 2.5 to 3.5 cents per kwH. The company has not yet released photos of the latest version of the new turbines. But apparently it uses airfoils, similar to airplane wings, that surround the turbine's curved, vertical blades. The interaction between the airfoils and blades produces low pressure which actually accelerates wind flow. Ron Taylor, the inventor new vertical design, does not see his vertical turbine supplanting the existing propeller infrastructure, but rather views it as supplementing the field.The company plans to sell turbines generating from 500 watts to 1 megawatt. The smaller ones are portable and can be used by farmers, the military and remote cabin owners.