Friday, September 12

Desalination Using Just Sunshine, Wind And Seawater

This amazingly simple and gorgeous utility scale solar-powered desalination plant also functions as a naturally cooled outdoor ampitheatre.

Paton's huge renewable desalinator, the Teatro Del Agua is explained by Paton in this youtube video. Paton describes how the project engineering works, and bears witness that solutions to water also solve the problems of the planet.

Grimshaw, the architects responsible for the beauty of the design says that the result is the world's first harbor-side development that is entirely cooled and irrigated with renewable technology.

The entire structure is orientated to the prevailing northeasterly wind off the seacoast, exploiting the natural resources of Spain's Canary Islands, but any seashore location with wind coming off the sea would work the same way.

It consists of a gigantic honeycomb lattice, with smaller grids (pink) in each section of the lattice. The entire structure is really a series of solar panels, evaporators (pink) and condensers (blue)

First hot salty air (hotpink arrows) flows through the grid (shown in pink) on the right, towards the blue tubes on the left. The blue tubes are the condensors. They are filled with very cold seawater pumped up from the deep ocean (thats why it has to be next to a deep water source: for the heat differential) with holes at the tops, under each solar panel "roof".

Solar powered fans blow the cold ocean spray out, towards the pink grid, against the prevailing warm sea wind coming through the grid. The combination of cold spray and warm air causes the salt to dry on the grid.

Once the warm humid sea air, cleansed of salt, reaches the columns it is rapidly cooled by the deep ocean seawater inside each column.

So it condenses and drips down each column sliding into containers at the bottom, and is ultimately stored underground, producing, Paton says: "enough freshwater to supply a city", depending on the size of this desalination structure and the city size and population, obviously.

The diagram below shows how the flow rates could be controlled by louvres on the leeward side. The reason that the entire structure tilts is that the flat "floors" you see in the diagram below are really solar panels, and thats why the structure is not built straight up and down. It is angled to maximize the amount of sunlight hitting the panels.

This project has a few siting requirements.

1. very steep beaches so cold deep water is close.
2. a steady wind direction off the water source.
3. good solar source

What makes Charles Paton's invention so exciting is that it uses the deep cold ocean water/warm land air differential like the cold water powered aircondioning systems that more cities and towns are turning to. But Paton takes that idea one step further in that this actually makes fresh water on a municipal scale using renewable power.

Charles Paton's previous project, the seawater greenhouse, also desalinates water naturally, using just sunshine, wind and seawater, and then uses that to grow crops, and he was lead engineer on Britian's Eden Project.

The simplicity of the technology and the gorgeous sweep of the form is light years away from the fossil-fueled desalination plants that this should replace.

Via Inhabitat

Related stories:
Air-Conditioning Cities With Deep Water
3000 Years Later A Ziggurat For 1 Million Citizens
Desalinated Seawater Greenhouse Cools Desert Agriculture

For Matternetwork