May 17, 2020

Ancient Passive Cooling Designs Provide Insight

modern architecture
ancient architecture
passive cooling
3 min
Pearl Academy of Fashion
Click here to experience this article in our digital reader Scorching heat and energy outages are quickly becoming a new reality for many people acro...


Click here to experience this article in our digital reader


Scorching heat and energy outages are quickly becoming a new reality for many people across the U.S. Last month, many suffered through some of the worst heat in the country's history without electricity. From Illinois to Virginia, hundreds of thousands of customers went without air conditioning for days as utilities scrambled to restore power.

What is becoming more apparent than ever is that many of today's “modern” buildings and homes weren't designed to handle the that kind of heat. Before the days of air conditioning, refrigerators and electrically powered fans, passive cooling techniques were used in architecture as salvation from the summer's sun. As sustainability becomes a growing concern for many designs, these techniques are starting to see a rebirth in today's green building scene. Fortunately, they can be quite beautiful too. 

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Most common in India, stepwells are small bodies of water created below ground or surrounded by walls above the ground. As the water evaporates in the enclosed area, it cools down adjacent spaces. In modern architecture, recycled water will do the trick too.

Architect Manit Rastogi tells CNN: "How did they think up something so elaborate and yet so simple in its basic philosophy? How do you begin to think that you can dig into the ground and use the earth as a heat sink, have access to water, put a pavilion into it so that its comfortable through the year? It takes a lot of technology for us to think up something that simple now."

modern stepwell at Pearl Academy of Fashion.jpg


To accomplish a natural indoor breeze, windcatchers are used to literally “catch” the wind and create air flow inside buildings. Extensively used in the Middle East, this technique can also function in one or more of three ways. When wind enters directly through a tall, capped tower with an opening, it creates a downward flow of air, or a natural breeze. As cool air from below fills the void, it allows for dense hot air to escape through the tunnel. Conversely, hot air may be pulled through the tunnel, where it is cooled in an underground space (sometimes with the use of water).


Perforated Double Skinned Exterior

Dressing the exterior of a building with a perforated screen is another highly effective and simple passive cooling technique. The extra wall helps diffuse natural daylight, while providing shade and illumination to indoor spaces. Placing one four feet outside the outer walls of a building also provides a hallway filled with natural air circulation.

The Pearl Academy of Fashion in Jaipur, India makes use of a couple of these techniques, including the perforated screen and a modern version of the stepwell to cool its indoor spaces. With an average daytime temperature of 113 F, those techniques are especially critical.

Just as Kris De Decker of No Tech Magazine “refuses to assume that every problem has a high-tech solution,” perhaps its time to start using a few old tricks to create a more bearable future in response to the environmental changes occurring at a rapid rate. 

perforated double skinned exterior.jpg




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Oct 19, 2020

Itronics successfully tests manganese recovery process

Scott Birch
3 min
Nevada firm aims to become the primary manganese producer in the United States
Nevada firm aims to become the primary manganese producer in the United States...

Itronics - a Nevada-based emerging cleantech materials growth company that manufacturers fertilisers and produces silver - has successfully tested two proprietary processes that recover manganese, with one process recovering manganese, potassium and zinc from paste produced by processing non-rechargeable alkaline batteries. The second recovers manganese via the company’s Rock Kleen Technology.

Manganese, one of the four most important industrial metals and widely used by the steel industry, has been designated by the US Federal Government as a "critical mineral." It is a major component of non-rechargeable alkaline batteries, one of the largest battery categories sold globally.

The use of manganese in EV batteries is increasing as EV battery technology is shifting to use of more nickel and manganese in battery formulations. But according to the US Department of Interior, there is no mine production of manganese in the United States. As such, Itronics is using its Rock Kleen Technology to test metal recoverability from mine tailings obtained from a former silver mine in western Nevada that has a high manganese content. 

In a statement, Itronics says that its Rock Kleen process recovers silver, manganese, zinc, copper, lead and nickel. The company says that it has calculated – based on laboratory test results – that if a Rock Kleen tailings process is put into commercial production, the former mine site would become the only primary manganese producer in the United States.

Itronics adds that it has also tested non-rechargeable alkaline battery paste recovered by a large domestic battery recycling company to determine if it could use one of its hydrometallurgical processes to solubilize the manganese, potassium, and zinc contained in the paste. This testing was successful, and Itronics was able to produce material useable in two of its fertilisers, it says.

"We believe that the chemistry of the two recovery processes would lend itself to electrochemical recovery of the manganese, zinc, and other metals. At this time electrochemical recovery has been tested for zinc and copper,” says Dr John Whitney, Itronics president. 

“Itronics has been reviewing procedures for electrochemical recovery of manganese and plans to move this technology forward when it is appropriate to do so and has acquired electro-winning equipment needed to do that.

"Because of the two described proprietary technologies, Itronics is positioned to become a domestic manganese producer on a large scale to satisfy domestic demand. The actual manganese products have not yet been defined, except for use in the Company's GOLD'n GRO Multi-Nutrient Fertilisers. However, the Company believes that it will be able to produce chemical manganese products as well as electrochemical products," he adds.

Itronics’ research and development plant is located in Reno, about 40 miles west of the Tesla giga-factory. Its planned cleantech materials campus, which will be located approximately 40 miles south of the Tesla factory, would be the location where the manganese products would be produced.

Panasonic is operating one of the world's largest EV battery factories at the Tesla location. However, Tesla and other companies have announced that EV battery technology is shifting to use of nickel-manganese batteries. Itronics is positioned and located to become a Nevada-0based supplier of manganese products for battery manufacturing as its manganese recovery technologies are advanced, the company states.

A long-term objective for Itronics is to become a leading producer of high purity metals, including the U.S. critical metals manganese and tin, using the Company's breakthrough hydrometallurgy, pyrometallurgy, and electrochemical technologies. ‘Additionally, Itronics is strategically positioned with its portfolio of "Zero Waste Energy Saving Technologies" to help solve the recently declared emergency need for domestic production of Critical Minerals from materials located at mine sites,’ the statement continues.

The Company's growth forecast centers upon its 10-year business plan designed to integrate its Zero Waste Energy Saving Technologies and to grow annual sales from $2 million in 2019, to $113 million in 2025.

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