Renewable energy comes in many forms with new innovative approaches being discovered very so often. A more recent approach to carbon neutral renewable energy can be found where two bodies of water meet. In an innovative approach, scientists have found a way to create electricity from locations where fresh water bodies (usually rivers) meet salty ocean water. The process has been proven to work; however, it requires a large quantity of water to make it profitable. The next phase will be to try out the process at scale and to ensure there are no negative impacts on the local ecosystem.
There are several ways to generate power from that mixing. And a couple of blue energy power plants have been built. But their high cost has prevented widespread adoption. All blue energy approaches rely on the fact that salts are composed of ions, or chemicals that harbor a positive or negative charge. In solids, the positive and negative charges attract one another, binding the ions together. (Table salt, for example, is a compound made from positively charged sodium ions bound to negatively charged chloride ions.) In water, these ions detach and can move independently.
By pumping the positive ions—like sodium or potassium—to the other side of a semipermeable membrane, researchers can create two pools of water: one with a positive charge, and one with a negative charge. If they then dunk electrodes in the pools and connect them with a wire, electrons will flow from the negatively charged to the positively charged side, generating electricity.