May 17, 2020

Hydrogen Storage Solution for an Intermittent Energy Source: Solar

4 min
A solution for the intermittency of solar
Click here to view this article in June's issue of Energy Digital Written by Nick Ni and Xu Liu of Verde LLC Today, energy is either transmitted...


Click here to view this article in June's issue of Energy Digital



Written by Nick Ni and Xu Liu of Verde LLC

Today, energy is either transmitted directly to the consumer through the grid or stored as backup power for future use via batteries, pumping water, etc. When it comes to solar and wind energy, it becomes extraordinarily difficult to take full advantage of the renewable sources using traditional methods of power transmission due to the varied locations of consumers and their pace of consumption.

Why solar farms need storage

Simply put, “We need storage because the sun doesn’t shine at night,” Dr. David Wogan wrote in the Scientific American.

Rapidly advancing technologies like energy storage are required to compensate for the short-term volatility of renewable energy sources. When integrating solar, for instance, power plant owners and grid operators face three major challenges:

  • Uncontrollable variability: Solar output varies in ways that generation operators cannot control, because sunlight may vary from moment to moment, affecting moment-to-moment power output. This fluctuation in power output results in the need for additional energy to balance supply and demand on the grid on an instantaneous basis, as well as ancillary services such as frequency regulation and voltage support.

  • Partial unpredictability: The availability of sunlight is partially unpredictable as solar PV systems require the presence of sunlight in order to operate.

  • Location dependence: Solar resources are based in specific locations and—unlike coal, gas, oil or uranium—can not be transported to a generation site that is grid-optimal. Generation must be co-located with the resource itself, and often these locations are far from the places where the power will ultimately be used. New transmission capacity is often required to connect solar resources to the rest of the grid.

Storing solar energy for later use can solve or mitigate the above inherent challenges it presents. We can overcome uncontrollable variability and unpredictability by storing excessive energy output from intense sunlight, and discharging stored energy to compensate for insufficient energy output when sunlight becomes weak. Storing solar energy also enables users to avoid waste of intensive sunlight due to the capacity limit of the grid, further promoting the overall utilization rate of solar farms.

Storing solar energy in hydrogen versus traditional storage solutions

The use of hydrogen storage offers solutions to the limitations of traditional storage systems:

  • Hydrogen storage solution costs much less than the battery storage solution, especially as the storage amount and time length continues to grow. The cost of hydrogen storage will approach the value of a storage tank during its life cycle, while the cost of batteries will continue to grow from inception.

  • Hydrogen storage life expectancy is much longer than a battery source, surviving up to 40 years without performance dampening, while battery performance fades quickly from repeated charging and discharging.

  • The hydrogen storage solution is available everywhere, whereas pumped storage and compressed air storage relies rigidly on geographic condition.

  • Existing tank trailers or natural gas pipelines can be used to transport the hydrogen in a flexible way, easily overcoming location dependency.

Additionally, generating hydrogen from solar electrolysis produces zero emissions of green house gasses, benefiting the environment and industries adopting “clean hydrogen” as feedstock by replacing traditional hydrogen suppliers who produce hydrogen from fossil fuels. This innovative approach ultimately makes the best use of clean, renewable energy sources.

While current electrolyzers in the industry are made to operate at a constant load and cannot follow a variable load, a system adapting variable load has to be established due to the intermittency of sunlight. According to Verde LLC, it’s not very difficult to establish a 2.5MW system adapting to a wide range of operating parameters. Given the fluctuating characteristics of solar panels, specialized electrolyzers would be an ideal fit.

The goal of hydrogen storage is to promote overall energy efficiency, which will also be the focus of hydrogen component manufacturers like Verde LLC, Ballard Power Systems and RIX Industries. To realize the highest overall efficiency of the storage system technically and economically, the concerns are on following aspects:

  • Redesigning the electrical inverter system according to specific condition of solar panel

  • Integrating the electrical inverter system, electrolyzer and hydrogen compressor & tank organically with improved overall efficiency

  • Designing a self-monitoring control system

The hydrogen storage solution enables solar farms to overcome inherent disadvantages of variability and unpredictability. Steadily operating solar farms, no matter utility or residential scale, can be realized by balancing how much solar energy turns into electricity, how much solar energy becomes hydrogen, and how much hydrogen converts back into electricity.

The US Department of Energy has released a number of reports, proving one simple but precious fact: hydrogen from renewable power like solar will dominate the feedstock market for many industries for decades to come. While our economy is slowly, but steadily, recovering, the solar energy industry is encouraged to take advantage of all the benefits that hydrogen technology presents to its ultimate success.

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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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