Mar 04 2008

Salty Water In...Fresh Water Out Posted by Angela Baker in windmill, wind power, reverse osmosis, electricity, Delft University

In many poor, third world countries, even having the resources to obtain electricity presents a problem.  Due to the lack of logistics, as well as the finances even if all of the logistics were in place, alternate methods are necessary in order

to have the basics that those in more financially fortunate areas of the world have.

 

A recent development at Delft University of Technology (TU Delft) in the Netherlands is a basic windmill that operates a pump, in turn utilizing reverse osmosis to output fresh water from the salty seawater that is put in.  Reverse osmosis is

 

a process used to purify concentrated solutions (often water with high levels of dissolved salts) in which pressure is applied to the more concentrated (or contaminated) solution on one side of a semipermeable membrane. The result is the movement of solvent, but not solutes, from the more concentrated side to the more dilute side, thus separating clean solvent from the concentrated solution.

 

So, basically, in laymens terms, reverse osmosis purifies the salt filled sea water so that it is able to be used for drinking water.  This development by Delft University is a critical advancement for small villages located in arid areas near the coast. 

 

Using windmills for desalination is nothing new.  These contraptions have previously been utilized and have been marketed already.  The windmills on the market currently use wind to produce electricity, and then store that electricity in order to begin the process of reverse osmosis.  Due to the expensive nature of this, as well as the fact that energy depletes during the procedure, TU Delft contrived a method that is a bit different.  Their technique is more energy and economically efficient.

 

Their method, unlike the others, runs directly on wind power.  The middle step of storing the electricity has been completely eradicated from the equation.  By storing water (which is more cost-effective than the electricity storage), calm periods, when there is no wind, are not as dire of an issue. 

 

The windmills that are in use for this process are slow-moving and strong.  The estimations that have been done up to this point on the windmills in question gauge them to be able to provide drinking water for a small village of around five hundred people.  This is not per week, or per month.  These estimates are on a per day basis through the reverse osmosis process of one windmill.  University of Delft is aware that an emergency supply needs to be in place to consume during the inevitable calm periods when the windmill is not able to use the wind power to operate the reverse osmosis procedure. 

 

The first test run for this new development is set for the beginning of March, in which the windmill that has been operating near Delft will be dismantled and relocated to Curacao.  The prospects of this succeeding will be monumental for villagers who lack fresh irrigation and who have to employ manual techniques to obtain any semblance of drinkable water.  The economical aspect, along with the quicker, machine-operated abilities villagers will now have to acquire such a basic need, will surely have colossal effects on poorer, third world countries.