NOVELTY - The device (1) has a frame (2) with at least two floats (3,4) on either side for positioning the device on a body of water with a flow under the frame, a span structure (5) on the floats, and at least two inline blade wheels (6,7) and additional blade wheel (8) provided under the span structure and connected individually or in combination via at least one shaft (9) to at least one generator in, at or on under the frame. The blades of the blade wheels extend at least partly into the body of water.    USE - Device for generating energy, in form of electric power.    ADVANTAGE - By placing sufficient number of blade wheels in a flow while covered by span structure, total electric power which can be generated is almost unlimited, while measures to combat if not eliminate annoyance and noise nuisance are made possible. Device can continue operating using array of blade wheels formed transversely of flow direction, even if one of wheels falls down or is defective. Blade wheels can be releasably connected to each other in groups to facilitate replacement or maintenance. Blade wheels can be kept small, limiting individual influence of wheels on ultimate effectiveness of device as well as minimizing device susceptibility to malfunction and costs associated with blade wheel transport. Flow can be stabilized in intermediate space between blade wheels lying one behind another, producing further increase in output. Maximum efficiency can be achieved from flow because blade wheels can be placed more deeply in body of water. Inlet grid can be arranged on frame and in front of wheels to prevent driftwood or other possibly damaging elements, including fish and other animals, being able to get into or between wheels as well as cause injury to fish and animals or damage to device. Closing element e.g. door, hatch, can function as wave surge breaker or damper to prevent damage to device in response to strong wave surge.    DESCRIPTION OF DRAWING(S) - The drawing shows the perspective view of a device for generating energy.    Device for generating energy (1)    Frame (2)    Floats (3,4)    Span structure (5)    Inline blade wheels (6,7)    Additional blade wheel (8)    Shaft (9)