How Much Water Does Ewicon Electrostatic Wind Energy Converter Use

Mike Barnard

SUMMARY: THE EWICON CONSUMES MORE WATER THAN ANY ELECTRICITY GAINED IS WORTH IN ANY REAL WORLD SITUATION.

Its always worth looking at the actual history of these wind energy "innovations".

THE ELECTROSTATIC WIND ENERGY CONVERTER: ELECTRICAL PERFORMANCE OF A HIGH VOLTAGE PROTOTYPE, DJAIRAM, D., ELECTRICAL ENGINEERING, MATHEMATICS AND COMPUTER SCIENCE, DISSERTATION, 2008-12-10, ISBN: 978-90-8559-482-6, uuid:e1cfdada-85ea-45c4-b6e4-b798abf5917e

The Electrostatic Wind Energy Converter: electrical performance of a high voltag

What can we glean from the above? That this technology is at least five years old. This isnt new news in other words.

What about installed locations?

In 2009, Mecanoo used the EWICON in their design of the Stadstimmerhuis 010 building in Rotterdam, with two EWICONS being deployed to create the 010 symbol on the roof.

Since Wednesday, 27 March 2013, a model has been on display outside the building of the faculty of Electrical Engineering, Mathematics and Computer Science at Delft University of Technology (TU Delft).

There are exactly two of them in the world, one a decorative and quite possibly not operational version on the roof of a building in Rotterdam and one outside of the faculty where the guy who wrote the thesis works.

What do they say as the most recent update on turning this into a production wind generator?

The EWICON will be developed further if funding is secured for follow-up research.

For context, Delft is wind generation research central. They have more money thrown at them for research into wind energy than pretty much any other university in the world. This technology managed to a little of it and is begging for more, which implies that the practical implications are pretty limited.

WHAT DOES THE THESIS SAY ABOUT EFFICIENCY?

... VARIOUS VERSIONS OF THE EWICON SYSTEM WERE TESTED... IN MOST CASES, THE MAXIMUM OUTPUT POWER WAS HIGHER THAN THE REQUIRED OPERATING POWER. COMPARED TO THE MAXIMUM CONVERTIBLE POWER IN THE WIND, THE NET POWER OUTPUT IS IN THE ORDER OF A FEW PERCENT.

Lets assume that theyve managed to improve on that since 2008 and actually approach 10%. Where does that put them in terms of efficiency compared to other wind generators? Well, it sucks frankly.

The rotor power co-efficient on the y axis is the number to look at here. The EWICONs 10% equates to 0.1 on that scale. That means that they are down with the Savonius wind turbine-- the least effective wind generator technology -- if they substantially increased their efficiency in the past five years. Note that still puts them well below the efficiency of 400 year old Dutch windmill technology or the old slatted wind mills used to pump waters on farms in North America and Australia.

Lets consider what they mostly ignored in their published effectiveness calculations: the costs of pumping and filtering water, the cost of the water itself, the cost of maintenance and the impacts of temperature. Fundamentally, they assume most of these things are free or ignore them because they are doing basic research and the research was done in a place with free, clean water under pressure that isnt particularly cold.

Lets examine those assumptions one by one:

* WATER IN MANY PARTS OF THE WORLD ISNT FREE. Just for quick examples, its a metered utility like electricity in Singapore, Las Vegas, Baltimore and Australia. It costs money. The trend is toward much more metered, costed water rather than away from it and higher prices for water. This thing is much, much worse than a dripping tap, more like a split garden hose in terms of water usage for a small device.
* They propose putting these devices on top of buildings. Any building over a handful of stories tall needs to manage its own water pressure either with a rooftop tank that it pumps water into or a pressurized system. Both of THESE REQUIRE ELECTRICITY TO PUMP THE WATER, WHICH COSTS MONEY.
* They propose putting these devices out to sea and using sea water. The sea water wont pump itself up into the device by itself. The sea water wont filter itself so that it doesnt directly clog the nozzles. The sea water wont remove minerals from itself so that they dont build up in the very small nozzles and clog them. These are ENGINEERING PROBLEMS RELATED TO LOCATING THESE DEVICES AT SEA, but when you are starting with such a poor performance factor, they make this technology a non-starter out of the box.
* Of course, theres the other really interesting question: what happens when temperatures drop below freezing? Given all of the holes in it, it probably wont be damaged too badly when all of the water in it freezes, but IT CERTAINLY WONT BE GENERATING ANY ELECTRICITY BELOW ZERO. And heating all of the fine tubes required to operate this in the face of a cold wind would require more energy than they are extracting because their efficiency is so poor.

Lets compare net electricity out of a modern wind turbine. I happen to have the ratio for net electricity drawn by a small wind farm in Australia at my fingertips. They generated 302 times the electricity that they required in a year for operating the two wind turbines. (Parasitic power and wind turbines. Sounds scary, but whats the real story?)

SO IS THIS A USEFUL TECHNOLOGY ANYWHERE?

In my opinion, its a neat bit of research with almost no practical use.

I cant even see it being useful in places where water is already misted into the air liberally to cool people down, typically hot tropical climates with very cheap water and then almost entirely on patios of restaurants and bars. Ive seen this done in Sao Paulo and Bangkok for example. The reason its not useful there is that they do this with fans to generate sufficient breeze to spread the mist, and the EWICON device would just obstruct the breeze instead of cooling patrons.

Ill be adding this to my list of bad bet technologies now that Ive looked at it more closely: Good and bad bets: new wind technologies rated.

See question on Quora

Source: renewable-technologies.blogspot.com