<p>The invention relates to an energy application system for applying energy to an object like a tumor. The system comprises several energy application devices (3) to be introduced into the object, which are adapted to receive electromagnetic radiation (2) and to generate heat depending on a frequency distribution of the received electromagnetic radiation, wherein the dependency of the heat generation on the frequency distribution of the electromagnetic radiation is different for different energy application devices. The system further comprises an electromagnetic radiation providing device (1) for providing electromagnetic radiation having a certain frequency distribution for stimulating the energy application devices to generate a predefined heat pattern. Since the dependency of the heat generation on the frequency distribution of the electromagnetic radiation is different for different energy application devices, even a relatively complexly shaped predefined heat pattern can relatively easily be generated by selectively addressing the energy application devices accordingly.</p>
