The idea that energy can be created from heat is a misnomer. Heat is energy. More specifically, heat is energy in motion, or moving from one area of the system to another. This fact has been studied countless times and has lead humanity to the discovery of the Laws of Thermodynamics (Thermodynamics: the science concerned with the relations between heat and mechanical energy or work, and the conversion of one into the other: modern thermodynamics deals with the properties of systems for the description of which temperature is a necessary coordinate [http://dictionary.reference.com/browse/thermodynamics]).
The first law of thermodynamics has two parts: the first part states 'In an isolated system the energy flow from any part of the system equals the heat flow to other parts of the system' and the second part states 'Energy can move around (and change form) but no new energy is created.' This follows the laws of the Conservation of Energy which states, "The law of conservation of energy states that energy may neither be created nor destroyed" (Law of Conservation of Energy). The second law of thermodynamics also has two parts: the first part states 'Heat flows from areas of "high" temperature to areas of "low" temperature' and the second part states 'Energy processes are irreversible (to reverse a process, it takes work [and work is energy]).'
The first part of the first Law is the proof that shuts the door on this idea. "...Energy flow from any part of the system equals the heat flow to other parts of the system.' Basically, this means Heat equals Energy.
The idea that energy can be created from heat, I believe, is a misrepresentation of the perception of how heat works in applications where it "produces energy" to create motion or other products of energy. If one were to look at the basic schematic of a heat engine, for example, one would find that the flow of heat "creates" work output. However, "work" too is another name for energy and since by the second part of the first law states that no new energy can be created in any sort of thermodynamic system we must conclude that no new energy has entered the system. Thus we must conclude that, within the bounds of a heat engine, the heat is converted into work and since both are forms of energy, no new energy has been created thus this follows the first law. The idea that heat is converts instead of creates is also expressed in the beginning of the second part of the first law, "Energy can move around (and change form)..." which reinforces our conclusion that heat cannot create energy, it is merely a form of energy and as such can be converted into other forms of energy.