Low-grade waste heat recovery system using stored hydropower
View Patent ↗A low-grade waste heat (“LGWH”), closed-circuit recovery system includes a storage chamber, a condenser, and a turbine. In the storage chamber, a working fluid, exposed to a waste heat source, is heated to vapor form and sent to a condenser at a higher elevation, where the working fluid is cooled. Upon condensation, the working fluid is dropped down onto a hydraulic turbine, the rotation of which generates power. The working fluid vapor can likewise cause rotation of a gas turbine.
1 . A low-grade waste heat (“LGWH”) recovery system, comprising:
a primary storage chamber comprising a working fluid and configured to receive waste heat from a heat source to heat the working fluid from a liquid form to a vapor form;
a floating condenser movable between a first position, at which the floating condenser is configured to receive the working fluid in vapor form from the primary storage chamber, and a second position, the floating condenser being configured to cool the working fluid back to liquid form, wherein the condenser is expandable;
two or more secondary storage chambers, each of the secondary storage chambers configured to receive the working fluid from the floating condenser at a different position between the first and second positions, wherein each of the secondary storage chambers are positioned at different elevations;
a primary turbine configured to receive the working fluid from at least one of the two or more secondary storage chambers and configured for rotation caused by descent of the working fluid therefrom;
wherein the LGWH recovery system is a closed system.
2 . The LGWH recovery system of claim 1 , wherein the second position is at a higher elevation than the first position.
3 . The LGWH recovery system of claim 1 , wherein the working fluid from each of the secondary storage chambers is collected in a central conduit configured to guide the working fluid to the primary turbine.
4 . A method of recovering energy, the method comprising:
connecting the primary storage chamber of the LGWH recovery system of claim 1 to the heat source;
recovering energy produced by rotation of the primary turbine.
5 . The LGWH recovery system of claim 1 , wherein the working fluid is water.
6 . The LGWH recovery system of claim 1 , wherein heat is transferred from the heat source to the primary storage chamber via coils, and wherein the working fluid is exposed to the coils.
7 . The LGWH recovery system of claim 1 , wherein the first position is at a higher elevation than the primary storage chamber.
8 . The LGWH recovery system of claim 1 , wherein the heat source is geothermal heat.