Abstract
We devised an apparatus (the SolarPump) that transports water from a reservoir to the distillate collection at a distance while distilling the water, using solar energy alone. The basic component of the system is a vaporizer, which is enclosed with a condenser. The vaporizer is based on the same principle as a porous cup atmometer. The potential energy level of water, which is lowered at the evaporating surface of a porous material when energy is provided for evaporation, causes water to flow continuously along the gradient of the potential energy from a reservoir to the evaporating surface. In other words, the system conduit is completely filled by water all the time, as long as energy and water are supplied. To confirm the above principle and evaluate its performance, we conducted a series of field tests using an experimental apparatus supplied with tap water. Its vaporizer included a vessel made of a transparent plastic tube, which is capped with a porous cup on the top and is open at its distal end into the reservoir. The condenser was supported and sealed with an acrylic outer tube. The apparatus yielded distillate proportional to the global irradiance, while transporting water 0.5 m above the reservoir. We also confirmed that the apparatus was capable of transporting water 2.0 m above the reservoir while performing distillation.
