Blue Energy powering our sustainable future

RED (Reverse ElectroDialysis) is a form of sustainable energy generation. The 'fuel' consists of fresh and salt water. Rivers flow into the sea and there the fresh water mixes with the salt water. These are the most obvious suitable locations for the application of RED. Some of the river water, along with seawater, is routed through a membrane stack in an enclosure called the REDstack. This is where the company REDstack got its name from. Salt and fresh water are mixed in a controlled manner in the stack and electrical energy is gained in this process. The resulting brackish water is returned to the sea and the electrical energy is delivered to the grid and distributed. The energy extracted in this way is commonly referred to as Blue Energy.

Global potential Blue Energy

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ED (ElectroDialysis) ED (ElectroDialysis) is a technology that is used to produce fresh water (e.g. drinking water) from salt or brackish water. By creating a voltage difference - also in a stack - the ions from the salt water are forced to move through the membranes, thus achieving desalination. REDstack aims at several applications in its markets.

REDstack originats as a spin-off company from the water technology institute Wetsus. In 2004, Wetsus institute started the theme 'Blue Energy' with the aim of generating energy from fresh and salt water. It soon became clear that this is a promising development and this was reason for a number of participants in Wetsus to establish REDstack. REDstack is owned by its founder and entrepreneur Pieter Hack: at the moment Pieter’s company W & F Technologies BV is mother and single shareholder of REDstack.

REDstack is working fully and successfully on the development, scale-up and future marketing of the generation of energy from differences in salinity, often referred to as Salinity Gradient Power (SGP). This form of energy - often now called Blue Energy - was first described in 1954 by the English researcher Pattle in the journal Nature. Of course, the principle had to be translated into actual process technology and equipment, which is technically sound, resistant and stays intact in operation, and which is price-wise accepted by users. That is the source of REDstack's mission.

We are increasingly trying to switch to sustainable energy such as wind and solar power. But in doing so, we are highly dependent on the fluctuating supply. Pieter Hack, founder / shareholder / Chairman of the Board of REDstack BV, explains how sustainable energy can be generated in a different way: by mixing fresh and salt water.