Battery Metals

If the blowup over President Trump’s new solar tariff proves anything, it proves that the renewable energy transition is inevitable. A new hydroelectricity project for the City of San Diego, California is a case in point. The city recently raised the level of an existing hydropower dam to hold more water, and now it is considering a massive new energy storage element that would help the grid support more wind and solar power.

The project provides support for the view that the new solar tariff is little more than a “speed bump” on the road to more sustainable future. Trump’s tariff is all but certain to disrupt the lives of individual solar workers, business owners and investors to some degree, but the overall impact is beginning to look like more smoke than fire.

Pushing the envelope on US hydropower

You wouldn’t know it from all the buzz over the latest high tech solar cells and wind turbines, but until very recently hydropower accounted for the lion’s share of the nation’s renewable energy pie.

That situation is rapidly changing. With wildlife conservation and environmental impacts in mind, there are few remaining opportunities to construct entirely new hydropower facilities in the US. In fact, this year the US Energy Information Agency expects wind energy to surpass hydropower for the first time ever.

There are still opportunities for growth in hydropower production, though. The US Department of Energy has been experimenting with ways to squeeze more electricity out of existing hydropower dams, and some interesting developments are occurring in the fields of wave energy, tidal energy and low impact hydrokinetic electricity.

It’s also worth noting that the importance of hydropower goes beyond the number of megawatts produced by the nation’s hydropower dams. The US Department of Energy foresees that hydropower provides the kind of stable, on-demand electricity supply that helps balance the variability of wind and solar.

Just a couple of weeks ago, the Energy Department posted an article describing how hydropower supports wind and solar. Here are some key points:

As the grid evolves in the 21st century, hydropower will be increasingly valued for its ability to respond quickly to disturbances in the grid and be dispatched on demand

Hydropower’s flexibility means it can help ensure power supply and quality even when high levels of variable power sources are on the grid. When countries run most or all of their power systems on renewable energy, it is often enabled by significant hydropower resources.

The Energy Department’s 2016 Hydropower Vision lays out the potential for the US to produce 30 gigawatts more hydropower than currently, with much of the increase coming from existing dams.

The 2016 report also supports an earlier Energy Department analysis from 2012, which describes scenarios for achieving 80 percent renewable energy by 2050.

Hydropower + energy storage for San Diego

That brings us to the new proposal to add an energy storage component to an existing hydropower facility owned by the San Diego Water Authority.

The project has its roots in the city’s recent $1.5 billion Emergency and Carryover Storage Project, designed to provide water supply for up to six months in case of systemwide distruption due to earthquakes or prolonged drought.

Two of four major facilities in sprawling project were constructed under design and management services provided by the A-list firm Black and Veatch. The company’s award-winning work included raising the existing San Vicente Dam an additional 117 feet, which doubled the size of the San Vincente Reservoir.

The latest twist is a proposal to add 500 megawatts of energy storage to the system. Dubbed the San Vicente Energy Storage Facility, it would have the goal of increasing “the efficiency and availability of renewable energy for the region,” as described by Black and Veatch. Here’s more:

The SVESF will store energy by pumping water to an upper reservoir when energy demand is low and releasing water from the upper reservoir through turbines when energy demand is high. The “pumped hydro” energy storage solution would support power grid operations and enable significant and sustained integration of renewable wind and solar energy into the power supply mix.

If you are already familiar with pumped hydro energy storage systems, this will ring a few bells:

During peak energy demand, water would flow downhill to turn hydroelectric turbines. During off-peak periods, including daytime when renewable energy supplies exceed demand, water would be pumped to the upper reservoir.

To ice the cake, the added revenue from SVESF would provide a funding stream for renovating the system’s aging infrastructure, without a consequent increase in water rates.

The new solar tariff: a hiccup, not a seizure

Circling back around to that solar tariff, it’s true that startups have been much in the spotlight as the US transitions to renewable energy, and some of them are exposed to the negative consequences of Trump’s decision.

However, diversified legacy companies like Black and Veatch also come in for their share of the credit for pushing the US renewable energy sector forward, and they may be less exposed to fallout from the solar tariff.

The San Diego energy storage proposal, for example, is just part of Black and Veatch’s long term strategy for growing its renewables business.

Last September, the company partnered with the Renewable Energy Test Center in California to launch a new service called “energy storage bankability.”

The new partnership will test and validate emerging energy storage technologies, providing a significant assist to new products on the verge of commercialization.

The Renewable Energy Test Center’s role is to help predict the lifetime performance of a product. Black & Veatch is contributing its experience in “independent assessment of alternative energy technologies and the design and construction of PV plants, microgrids and other systems that deploy PV and energy storage technologies.”

Solar tariff or not, it looks like renewables have a bright future in the US.

Through the use of dry fermentation technology, Bekon biogas plants offer the option of advanced and efficient biogas production. With a low energy consumption, they achieve a constant, maximum output of high methane content biogas, through fermentation of solid substrates. These include, for example, organic and garden waste, organic fractions from residual waste processing, solid cattle manure and other stackable organic wastes. The resulting digestate is noted for its excellent structural properties and a comparatively low water content, which therefore makes it ideally suited for aerobic conditioning and further treatment to high grade, nutrient rich compost or organic fertiliser for soil improvement.

The Bekon Mini system allows this type of dry fermentation to be conducted even in the smallest spaces and can also be used with low input quantities. The new biogas plant in Enger has an annual input capacity of 8,500 tonnes of biowaste (kitchen and garden waste), from which some 1.1 million m³ of biogas can be produced. This is used both for the generation of electricity (1,210,000 kWh/a) and for heating (1,200,000 kWh/a). It is calculated that this will allow about 350 households to be supplied with electricity from the Bekon system.

Furthermore, Bekon systems are not just noted for their high operational stability and safe disposal, but also for the greatest possible energy efficiency. As a result, only a fraction of the energy generated flows back into the plant to supply its own energy demand. In Enger, only 8% of the electricity generated is used for operation of the biogas plant itself. The remaining majority of 92% is fed into the regional power grid. In addition, the recovered waste heat will, in the near future, be utilised externally, for example, through feed-in to a local or district heating network or for use in drying materials. In this case as well, only a small fraction of the thermal energy is needed for operation of the plant itself.

A type of battery first invented nearly five decades ago could catapult to the forefront of energy storage technologies, thanks to a new finding by researchers at MIT.

The battery, based on electrodes made of sodium and nickel chloride and using a new type of metal mesh membrane, could be used for grid-scale installations to make intermittent power sources such as wind and solar capable of delivering reliable baseload electricity.

New metal-mesh membrane could solve longstanding problems and lead to inexpensive power storage.

The findings are being reported today in the journal Nature Energy, by a team led by MIT professor Donald Sadoway, postdocs Huayi Yin and Brice Chung, and four others.

Although the basic battery chemistry the team used, based on a liquid sodium electrode material, was first described in 1968, the concept never caught on as a practical approach because of one significant drawback: It required the use of a thin membrane to separate its molten components, and the only known material with the needed properties for that membrane was a brittle and fragile ceramic. These paper-thin membranes made the batteries too easily damaged in real-world operating conditions, so apart from a few specialized industrial applications, the system has never been widely implemented.

But Sadoway and his team took a different approach, realizing that the functions of that membrane could instead be performed by a specially coated metal mesh, a much stronger and more flexible material that could stand up to the rigors of use in industrial-scale storage systems.

“I consider this a breakthrough,” Sadoway says, because for the first time in five decades, this type of battery — whose advantages include cheap, abundant raw materials, very safe operational characteristics, and an ability to go through many charge-discharge cycles without degradation — could finally become practical.

While some companies have continued to make liquid-sodium batteries for specialized uses, “the cost was kept high because of the fragility of the ceramic membranes,” says Sadoway, the John F. Elliott Professor of Materials Chemistry. “Nobody’s really been able to make that process work,” including GE, which spent nearly 10 years working on the technology before abandoning the project.

As Sadoway and his team explored various options for the different components in a molten-metal-based battery, they were surprised by the results of one of their tests using lead compounds. “We opened the cell and found droplets” inside the test chamber, which “would have to have been droplets of molten lead,” he says. But instead of acting as a membrane, as expected, the compound material “was acting as an electrode,” actively taking part in the battery’s electrochemical reaction.

“That really opened our eyes to a completely different technology,” he says. The membrane had performed its role — selectively allowing certain molecules to pass through while blocking others — in an entirely different way, using its electrical properties rather than the typical mechanical sorting based on the sizes of pores in the material.

In the end, after experimenting with various compounds, the team found that an ordinary steel mesh coated with a solution of titanium nitride could perform all the functions of the previously used ceramic membranes, but without the brittleness and fragility. The results could make possible a whole family of inexpensive and durable materials practical for large-scale rechargeable batteries.

The use of the new type of membrane can be applied to a wide variety of molten-electrode battery chemistries, he says, and opens up new avenues for battery design. “The fact that you can build a sodium-sulfur type of battery, or a sodium/nickel-chloride type of battery, without resorting to the use of fragile, brittle ceramic — that changes everything,” he says.

The work could lead to inexpensive batteries large enough to make intermittent, renewable power sources practical for grid-scale storage, and the same underlying technology could have other applications as well, such as for some kinds of metal production, Sadoway says.

Sadoway cautions that such batteries would not be suitable for some major uses, such as cars or phones. Their strong point is in large, fixed installations where cost is paramount, but size and weight are not, such as utility-scale load leveling. In those applications, inexpensive battery technology could potentially enable a much greater percentage of intermittent renewable energy sources to take the place of baseload, always-available power sources, which are now dominated by fossil fuels.

The research team included Fei Chen, a visiting scientist from Wuhan University of Technology; Nobuyuki Tanaka, a visiting scientist from the Japan Atomic Energy Agency; MIT research scientist Takanari Ouchi; and postdocs Huayi Yin, Brice Chung, and Ji Zhao. The work was supported by the French oil company Total S.A. through the MIT Energy Initiative.

Seeing the momentum moving toward electric vehicles, the Automotive Research Association of India (ARAI) is working on building a facility that will test EV batteries.

The research association of the Automotive Industry with Ministry of Heavy Industries and Public Enterprises, Government of India has also announced its plan for building the e-mobility centre of excellence to test all set of vehicles from two-wheelers to buses.

The e-mobility centre will be ready in next few months, where as the battery testing facility will be ready in next six months. The testing body is already equipped with facilities to test EVs, motors and controllers.

“To test all set of vehicles, we have scaled up the facility and it will be ready in next few months,” said AA Badusha, senior deputy director & head Homologation Management, Regulation & Vehicle Evaluation, ARAI.

He also confirmed ETAuto that the research association is currently working on the battery testing facility in Chakan, Pune. This facility will test the battery behaviors and will analyse its load. But this is not from the regulation point of view but more on understanding the overall performance of the battery and the vehicle.

As the government is putting thrust on electric vehicles, original equipment manufacturers (OEMs) are also readying their blueprint to launch electric vehicles (EV) to become future ready.

Currently, Suzuki Motor with SMC, Denso Corporation, and Toshiba Corporation is setting up a lithium-ion battery plant in Gujarat. The venture is expected to be operational in 2020.

Mahindra & Mahindra and Tata Motors, currently, are manufacturing electric vehicles in India, while Ashok Leyland, Maruti Suzuki India, Toyota and Renault have also started working on their respective products.

At the same time, a series of startups are also working on this area. A few of them have already launched and some are planning to launch their EVs in the near future.

A joint report by NITI Aayog and Rocky Mountain estimates that India’s leapfrog vision of a shared, electric, and connected mobility system could create a $300-billion domestic market for electric vehicle batteries by 2030, representing nearly two-fifths of global EV battery demand.

Moreover, the report also predicts that the country can capture 25-40 per cent of the total economic opportunity, represented by EV battery manufacturing under a scenario, where India imports lithium-ion cells and assembles these cells into battery packs.

Metro rail systems in India have redefined the urban experience for many city dwellers. In cities with a functional metro system, commuters have an option for cheap and affordable public transport. Additionally, the use of regenerative braking technology (in some instances) has allowed metro rails systems to save on power and thus reduce the release of harmful carbon emissions.

In adopting the regenerative braking technology, each train of the Chennai metro rail system generates approximately a third of the power it consumes to run, according to a report by the Times of India.

Speaking to the publication, Chennai metro rail officials claim that a four-car rake running 400 km per day can generate power worth approximately 1,900-kilowatt-hour (kWh). To operate 400 km per day, a train consumes nearly 6,300kWh.

“The power is used for lighting and running auxiliary systems on board,” a metro rail official told the publication. “In any transport system, fuel is the biggest expenditure. But the regenerative braking system can reduce dependency on the state grid. All our cars have traction systems to generate power; in EMUs [electrical multiple units], only the locomotive does,” the official added.

How does this technology work?

Whenever a vehicle slows down using brakes, it loses its kinetic energy in the form of heat in the brake pads. With regenerative braking, this wastage is avoided. In these trains, the three-phase traction motors perform the role of generators whenever a driver presses the brakes, converting the kinetic energy of the train into electrical energy. This power then goes into the overhead lines.

Since the Chennai metro rail system, which operates 13 trains on 29 kms of operational line, meets nearly 30% of its energy requirements through its own trains, there is a significant reduction in the use of fossil fuel-generated power.

Even the much-lauded Delhi Metro adopted the regenerative braking system, which prevented 90,000 tonnes of harmful CO2 from entering the city’s air from 2004 to 2007. Another significant advantage is that commuters indirectly reduce the amount of carbon emissions released in the air, by not travelling on private cars and motorcycles.

On January 25, 2018, Eneo has commissioned the first ever solar/thermal hybrid plant, in Cameroon, in Djoum, Southern Cameroon. With this infrastructure, built by the Spanish ELECNOR (CFA319 million), the electricity company moves into photovoltaic.

“With the commissioning of Djoum pilot project, we are demonstrating through deeds that sun shines for everybody and, we want to encourage local economic actors to invest in this new green energy which is now a genuine opportunity“, said Joël Nana Kontchou, managing director ENEO.

He explained that ENEO chose the hybrid plant for its first solar project because this solution would help save operating costs and guarantee energy supply.

With a field of 600 solar panels, the largest till-date in Cameroon, Djoum solar park will produce 186 KW and, it is combined with a 1,115 KW thermal plant.

“Specifically, in Djoum, during daytime, we inject both thermal and solar power in the electric grid. The fuel saved can thus be used to meet the demands. Moreover, the operational time of the thermal plant is reduced. This limits the risks of outbreaks and thus allows an improved availability of the machines”, explained Eugène Ngueha, director of technical activities at ENEO Cameroon.

The company revealed that it had already conducted studies on six other sites, Lagdo, Garoua, Lomié, Bertoua, Yokadouma, and Ngaoundal namely. ENEO’s solar programme should create hybrid plants at the isolated thermal plants installed in those regions.

Moreover, Joël Nana Kontchou said 3 solar plants with 35 MW generating capacity would be installed in the northern region, this region being the most isolated, according to a research conducted by the electricity regulatory agency. In detail, it would be a 10 MW plant in Guider, 10MW in Ngadoundéré and 15 MW in Maroua.

Eneo estimated that these solar plants whose procurement procedures were ongoing would be operational by March- April 2019.