Techniques for solar thermal water purification by recycling photovoltaic reflection losses are provided. In one aspect, a solar thermal water purification system includes: a water purification component for desalinating salt water, the water purification component having multiple stages through which the salt water passes, and condensers in each of the stages; and a photovoltaic component configured to heat the salt water prior to the salt water entering a first stage of the water purification component, wherein desalinated water evaporates and condenses in each of the stages to be collected as pure water. A system using reverse osmosis and a heat-driven water pump is also provided. Methods for water purification are also provided.

A portable water purification system is disclosed. The system can have a water storage receptacle, a reverse osmosis filter, a pump, and a solar panel array group. The reverse osmosis filter can be configurable to convert source water into drinkable water, and the pump can be configurable to provide the source water from a water source to the reverse osmosis filter. The array group can have at least one bi-fold solar panel array, and the array group can be configurable to provide power for the pump. The water storage receptacle can be configurable to contain the drinkable water in one configuration and configurable to contain at least one component of the purification system for storage in another configuration.

A method for regulating ion transport between first and second regions of a liquid solution containing ionic species in at least one of said first and second regions, the method comprising applying a voltage on an electrically conductive mesoporous carbon membrane situated between said first and second regions of the liquid solution, wherein liquid flow between first and second regions is permitted only through said mesoporous carbon membrane, and the applied voltage is selected to modulate the degree of ion transport between said first and second regions, wherein an increase in applied voltage results in a reduction in the degree of ion transport between said first and second regions, optionally up to a critical voltage at which ion transport ceases.

A water purification system utilizes an ionomer membrane and mild vacuum to draw water from source water through the membrane. A water source may be salt water or a contaminated water source. The water drawn through the membrane passes across the condenser chamber to a condenser surface where it is condensed into purified water. The condenser surface may be metal or any other suitable surface and may be flat or pleated. In addition, the condenser surface may be maintained at a lower temperature than the water on the water source side of the membrane. The ionomer membrane may be configured in a cartridge, a pleated or flat plate configuration. A latent heat loop may be configured to carry the latent heat of vaporization from the condenser back to the water source side of the ionomer membrane. The source water may be heated by a solar water heater.

In one embodiment, a renewable energy generation and storage system and method is provided for storing both electrical and thermal energy that includes a forward osmosis system for drawing water across a membrane such that the water drawn across the membrane is used to dilute an osmotic ionic draw solution and the diluted osmotic ionic draw solution is used to drive a hydro-turbine; an FO-EED separation system for separating the drawn water from the ionic draw solution using renewable electrical energy and an osmotic polymer introduced in the FO-EED system during use, so that the ionic draw solution is re-concentrated by using electrical energy, such that the water from the ionic solution combines with the concentrated osmotic polymer; a coalescer configured to receive compressed CO.sub.2 to separate the water from the polymer by having the polymer absorb the compressed CO.sub.2 during use; and using thermal energy for separating the CO.sub.2 from the polymer, thereby regenerating a concentrated polymer solution.

The solar desalination system is a hybrid system combining a Fresnel solar concentrator with a desalination chamber, and which uses membrane distillation for desalination of seawater. The desalination chamber includes a lower wall having a central absorber base, at least one sidewall, and an upper wall. A pair of hydrophobic membranes are mounted within the desalination chamber such that a central chamber is defined therebetween above the absorber base. The desalination chamber is suspended above a linear Fresnel reflector array so that the absorber base is positioned at a focal line thereof. Seawater is fed into the central chamber, where it is heated to produce water vapor, which passes through the pair of hydrophobic membranes into a pair of condensate retrieval chambers. The water vapor cools in the pair of condensate retrieval chambers, and may then be removed in the form of pure water.

A membrane for water collection may include a sheet having a top surface and a bottom surface, and a plurality of conical structures disposed on the top surface of the sheet, the conical structures comprising a hydrogel material. Each conical structure of the plurality of conical structures may have a height of 1 mm to 50 mm, wherein height is measured from the top surface of the sheet to an apex of a conical structure. Each conical structure of the plurality of conical structures may have an apex angle of 10 to 60 degrees.

A water purification system utilizes an ionomer membrane and mild vacuum to draw water from source water through the membrane. A water source may be salt water or a contaminated water source. The water drawn through the membrane passes across the condenser chamber to a condenser surface where it is condensed into purified water. The condenser surface may be metal or any other suitable surface and may be flat or pleated. In addition, the condenser surface may be maintained at a lower temperature than the water on the water source side of the membrane. The ionomer membrane may be configured in a cartridge, a pleated or flat plate configuration. A latent heat loop may be configured to carry the latent heat of vaporization from the condenser back to the water source side of the ionomer membrane. The source water may be heated by a solar water heater.

A liquid desiccant regeneration system comprises an electrodialysis apparatus having first and second reservoirs, wherein concentration of an input solution in the first reservoir increases to a threshold concentration and concentration of the input solution decreases in the second reservoir during an operation mode. A first redox-active electrolyte chamber comprises a first electrode and a first solution of a redox-active electrolyte material and has a reversible redox reaction with the first electrolyte material to drive an ion into the first reservoir. A second redox-active electrolyte chamber comprises a second electrode and a second solution of a redox-active electrolyte material and has a reversible redox reaction with the second electrolyte material to accept an ion from the second reservoir. A first type of membrane is disposed between the first and second reservoirs, and a second type of membrane, different from the first, is disposed between the respective electrode chambers and reservoirs.

A system comprises an electrodialysis apparatus, which includes first and second reservoirs, wherein a salt concentration in the first reservoir reduces below a threshold concentration, and salt concentration in the second reservoir increases during an operation mode. A first electrode comprises a first solution of a first redox-active electrolyte material, and a second electrode comprises a second solution of a second redox-active electrolyte material. In a first reversible redox reaction between the first electrode and first electrolyte material at least one ion is accepted from the first reservoir, and in a second reversible redox reaction between the second electrode and second electrolyte material at least one ion is driven into the second reservoir. A first type of ion exchange membrane is disposed between the first and second reservoirs, and a second type of ion exchange membrane, different from the first type, is disposed between the respective electrodes and reservoirs.