The invention discloses a
system for storing energy by positive and reverse organic Rankine cycles. The
system comprises a low-pressure and high-
pressure work medium storage tanks coated with heat-insulating material
layers and low-temperature and high-temperature
phase change materials which are respectively arranged at the low-
pressure work medium
storage tank and the high-
pressure work medium
storage tank; an air
heat exchanger is arranged in the low-pressure work medium
storage tank and is communicated with the outside; and the upper end of the low-pressure work medium storage tank is divided into two paths, wherein one path is sequentially connected with a compressor and the high-pressure work medium storage tank through a
program control valve and the other path is sequentially connected with an expander and the high-pressure work medium storage tank through another
program control valve. The
energy storage process of the
system is as follows: the compressor is opened for reverse
Rankine cycle, a work medium in the low-pressure work medium storage tank is compressed to the high-pressure work medium storage tank and condensed heat of input work and low-temperature
phase change work medium in the low-pressure work medium storage tank is stored into
dissolution heat of the high-temperature
phase change work medium in the high-pressure work medium storage tank; the power
generation process is as follows: the expander is opened for positive
organic Rankine cycle, the work medium does work in the high-pressure work medium storage tank and then enters the low-pressure work medium storage tank and is condensed by a low-temperature phase change work medium and air in the low-pressure work medium storage tank; and meanwhile, the high-temperature phase change work medium in the high-pressure work medium storage tank discharges heat and is condensed. According to the system disclosed by the invention, the energy is stored by using phase change,
energy storage density is great and the storage and the release of
electric energy can be realized stably and continuously.