FIELD: power engineering. SUBSTANCE: invention relates to design of autonomous powerless power plants. Proposed device for generating electricity from the tides comprises vertical support 1, pneumatic chamber 2 moving along support 1, step-up gear 9, power rope 8 and electric generator 10. Device incorporates second vertical support 3. On supports 1 and 3 there are units 5, 6, 7, through which rope 8 is passed through reduction gear 9. One end of rope 8 is secured on pneumatic chamber 2. Other end of rope 8 is connected to load-counterweight 4. Load-counterweight 4 is installed through unit 7 on support 3. Reduction gear 9 is connected directly to generator 10. EFFECT: invention is aimed at simplification of the design.