NOVELTY - A thermoelectric device (130) comprises first element for collecting heat from heat source; second element in spaced relations from first element for dissipating heat from first element; and core (134) positioned between elements for converting heat from first element to useful energy, where core has nanotube thermal element exhibiting relatively high Seebeck coefficient increasing with increase in temperature, and conductive element (143) exhibiting relatively high transition temperature. The thermal element has sheet of carbon nanotubes doped with p-type (141) or n-type dopant (142).    USE - As thermoelectric device for use as solar energy collector or harvester with a conversion efficiency of at least about 10-15%; in battery charging applications; as a large area power generator for one of houses, buildings or cities; as heat or energy engine to directly transform heat to electrical work; as an energy generator from waste heat; as a combustion engine for automobile, marine, aerospace or space applications; as a low temperature energy harvester for sub-zero temperature applications; and for generating power (claimed).    ADVANTAGE - The device exhibits high specific power density. The design of the thermoelectric device allows the device to operate at high temperature and to generate high power output, despite being light weight. The thermoelectric device is efficient, yet lightweight; can operate at high temperature; and can generate the necessary voltage to permit useful applications. The device can efficiently harvest the waste heat; convert the waste heat to power; and redirect the power to various machines, electronic devices and power systems so as to enhance efficiency and reduce overall power usage.    DETAILED DESCRIPTION - A thermoelectric device (130) comprises a first element designed to collect heat from a heat source; a second element in spaced relations from the first element for dissipating heat from the first element; and a core (134) positioned between the first element and a second element for converting heat from the first element to useful energy, where the core has a nanotube thermal element exhibiting a relatively high Seebeck coefficient that increases with an increase in temperature, and a conductive element (143) exhibiting a relatively high transition temperature. The elements coupled to one another allows the core to operate within a high temperature range. The first element and second element are made from aluminum nitride. The nanotube thermal element has a density range of 0.1-1.0 g/cc; and exhibits relatively low thermal conductivity. The core comprises an array of the nanotube thermal element and conductive element in linear alignment, where the array is wrapped about an axis to form a disk. The nanotube thermal element includes a sheet of carbon nanotubes doped with one of a p-type dopant (141) or n-type dopant (142). The thermal element includes several carbon nanotube sheets, each placed on top of the other, so as to increase the power generated by the device. The conductive element includes one of copper, nickel or other similar metallic materials; or includes a glassy carbon material. The device further includes high temperature polymer or a polyamide material for use as a stiffener or insulator in the core. The core comprises several nanotube yarns extending between the first element and the second element, where each yarn is coated along its length with a segmented pattern of a metallic material, so that between consecutive coated segments is a segment of non-coated nanotube yarn; or comprises at least one panel. Each coated segment of the yarn acts as a conductive element, while each non-coated segment of the yarn acts as a thermal element. The coated segments includes one of copper, nickel or other similar metallic materials. The nanotube yarns minimizes heat transfer from one element to the other element. The panel includes a coating of a metallic material on the side having the thermal elements. The metallic coating includes one of copper, nickel or other similar metallic materials. The panel is made from one of aluminum nitride, mica or other similar materials. The conductive element is a metallic wire acting as an n-type element. The wire is made from one of copper, nickel or other similar metallic materials. The first and second element is made from alumina. INDEPENDENT CLAIMS are included for the following:    (1) generating power involving: providing thermoelectric device having first element designed to collect heat from a heat source, second element in spaced relations from the first element for dissipating heat from the first element, and core positioned between the first element and a second element for converting heat from the first element to useful energy; positioning the device so as to permit the first element to collect heat from a heat source; driving the collected heat across the core to the second element due to a temperature differential between the first element and the second element; and allowing the core of the device to convert the heat being transferred across it to be converted to power. The method further includes directing the power generated to another device to permit that device to operate; and    (2) manufacturing thermoelectric device involving providing at least one nanotube thermal element exhibiting a relatively high Seebeck coefficient that increases with an increase in temperature; coupling the thermal element to a corresponding conductive element exhibiting a relatively high transition temperature to provide a core element; and positioning the core element between a first element designed to collect heat from a heat source, and a second element in spaced relations from the first element for dissipating heat from the first element.    DESCRIPTION OF DRAWING(S) - The figure shows schematic view of thermoelectric device having alternating array core for energy harvesting.    Thermoelectric device (130)    Top plate (131)    Bottom plate (132)    Supports (133)    Core (134)    p-Type elements (141)    n-Type elements (142)    Conducting element (143)