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In the second installment of this two-part series, we will focus on solar power, energy storage and battery technologies. President Barack Obama’s challenge during the State of the Union address was to generate 80 percent of the electricity from renewable sources by the year 2035.
By Michael Montgomery— Cross-posted from Rare Earth Investing News
The most comprehensive and relaevant plan to achieve the President’s challenge comes from internet giant Google. Google’s plan consists of replacing all coal fired plants by 2030, and moving to greener methods of energy production which could result in a net economic savings of $820 billion over 22 years. The economic benefits to the US are:
- Fossil fuel-based electricity generation by 88%
- Vehicle oil consumption by 44%
- Dependence on imported oil (currently 10 million barrels per day) by 37%
- Electricity-sector CO2 emissions by 95%
- Personal vehicle sector CO2 emissions by 44%
- US CO2 emissions overall by 49% (41% from today’s CO2 emission level)
Solar Electrical Generation
There are two forms of solar power generation that are in use today. First is photovoltaic (PV) cells, also known as solar panels, and the other is Concentrated Solar Power (CSP), a system that oncentrates sunlight to a tower, to power the generator.
Photovoltaic cells
Photovoltaic cells come in a variety of different styles and material compositions. The most common type of solar panel is made from silicon. Silicon-based panels, while the most efficient, are also the most costly. To counter the high costs of silicon panels, a new wave of panels called ‘thin-film’ has been introduced. Thin-film panels are, typically, made from Cadmium-Telluride (CdTe), and Copper-Indium-Gallium-Selenide(CIGS) and have succeeded in lowering costs while maintaining high levels of efficiency.
First Solar is one of the largest manufacturers of cadmium-telluride panels. These panels have reduced the cost of power generation to below $1 per watt. Cadmium, unfortunately, is one the most toxic chemicals on earth, and has been banned by the European Union. The long term cost incurred with handling cadmium to build First Solar’s panels, as well as the use of toxic chemicals to generate ‘green’ energy seem unsustainable. Furthermore, the use toxic chemicals such as cadmium, to generate “green” energy pose a fundamental dilemma for the technologies industry.
Copper-indium-gallium-selenide
CIGS solar panels have exceeded CdTe panels in efficiency. Candace Lombardi reported for Cnet News that “The Department of Energy has confirmed that MiaSole’s thin-film photovoltaic (CIGS) solar modules have reached an efficiency of 15.7 percent (in lab tests).” This rapid increase in efficiency is tantamount for this solar technology to revolutionize the industry.
CIGS solar panels are made from a combination of materials and the adoption of these solar panels will likely increase demand for copper and molybdenum. The manufacturing process of CIGS panels has the active layer in a panel placed directly onto molybdenum coated glass sheets or steel bands while in its polycrystalline form. This process requires less energy than silicon panels, which require the growth of large crystals, a necessary component for the fabrication of crystalline silicon solar cells. Unlike crystalline silicon, CIGS substrates can be thin, flexible, light, and versatile.
Efficient, economically viable CIGS solar panels have been developed by several companies, such as NanoSolar, Solyndra, Global Solar Energy,Sulfurcell, AQT Solar, and MiaSole, to name a few.
Concentrated solar power
There are four common forms of Concentrated Solar Power: parabolic troughs, solar power towers, dish stirlings and Fresnel lenses. CSPs use mirror arrays to concentrate the sun’s power onto a heating element. The manufacturing costs of CSPs are relatively low, and the end result is capable of producing vast amounts of energy. Unlike photovoltaic power, CSPs don’t require the same amount of resources to generate power. Furthermore, designed with arid, desert climates in mind, CSPs are capable of taking advantage of the high heat capabilities of molten salt or synthetic oils as substitutes for water in tower systems.
Parabolic Troughs
The most common CSP form is parabolic trough, which uses half-pipe shaped mirrors and a series of tubes that heat water to spin turbines. The world’s most productive parabolic trough system is in California and is run by NextEra Energy Resources (NYSE:NEE). The company’s Kramer Junction and Harper lake plants generate a combined 310 Mw. NextEra uses an advanced design of mirrors which incorporates silver into the glass to increase reflectivity.
Solar power towers
Solar tower systems are more efficient and costs far less to generate electricity. Tower systems have an array of mirrors called “heliostats’ that focus the heat towards a tower in the center of the array. Spain has been on the forefront of these technologies with multiple projects. The country’s PS10 solar tower, which is run by Abengoa Solar, generates 11 megawatts and has €35 million cost to date.
In the US, there is only one CSP solar power tower plant which is located in Lancaster, Ca. The plant is run by eSolar, and generates 5Mw. “The plant produces power at less than the retail rate for electricity in California, which is 13 cents per kilowatt-hour,” reported Martin LaMonica, for Cnet News.
In a study by Jonathan Gwiazda and Francis A. DiBella for Northeastern University, the concept of using the footprint of open pit mines as a stadium for CSP projects was explored. The study highlighted the benefits of re-purposing a pit mine by taking advantage of the existing infrastructure, such as the buildings and roads. Furthermore, using open pit mines will eliminate the free-standing structure of the tower by way of using the pit for structural support.
Battery technology
Vanadium redox battery (VRB) technology is set to revolutionize grid level power storage. These batteries are special because of the number of deep cycles they can withstand over the course of their lives and rapid charge rate. Battery systems that use vanadium redox batteries have the ability to store massive amounts of energy. These VRB systems use about one to five tons of vanadium pentoxide, which at the current price of around $7 per pound can result in battery prices to be quite high. With the market in a short supply of high-grade vanadium pentoxide, some VRB manufacturers are paying more than $7 per pound for the product.
Michael Hyslop, Director of Corporate Development for American Vanadium spoke with Resource Investing News about VRB systems in relation to grid level storage.
“The market for vanadium redox batteries is huge because the need for larger grid level storage, not just for wind or solar power storage, but grid in general is rising. In order to raise grid capacity you don’t have to flow electricity at peak times. The cost of flowing energy at those times is astronomical… and the amount of vanadium electrolyte that needs to be produced to meet new market demand it is astronomical,” stated Hyslop.
The road to grid level storage from VRB systems is not an easy one. Currently, there isn’t enough vanadium production for these batteries to fully take off. “There are technical hurdles that we believe can be overcome fairly easily, and the only reason they haven’t been overcome, is because there has never been a guaranteed cheap supply of vanadium electrolyte,” said Hyslop. He also stated that due to level of interest and the funding that is going toward the production of these batteries, the shortcomings in terms of energy density may be solved this year.
Two companies currently focused on filling the gap with their vanadium resources are American Vanadium and Energizer Resources.
American Vanadium, (formerly Rocky Mountain Resources) (TSXV:AVC), is working on its Gibellini property in Nevada. The goal is for the Gibellini property to provide the domestic US market with low cost vanadium.
Energizer Resources (TSXV:EGZ) has concentrated their efforts on the Green Giant property in Madagascar. Green Giant has an NI 43-101 indicated resource of 49.5 million tonnes of vanadium as well as an inferred resource of 9.7 million tonnes.
There are several companies who manufacture vanadium redox batteries including Japan’s Sumitomo Corp., China’s Prudent Energy, and Germany’s Cellstrom.
Vanadium-lithium batteries for electric vehicles
Google’s plan calls for 90% of new car sales in 2030 to be plug-in vehicles, which should equate to 41% of the US fleet that year. On the forefront of making electric vehicles a wide-spread reality are vanadium-lithium batteries. “Germany’s DBM Energy… refitted into an Audi A2 electric car, the result was the setting of a new distance world record, with the car driving over 600 km (372 miles) on a single charge. Even more impressive, DBM Energy says the battery shows 97% efficiency and can be recharged in as fast as six minutes using any standard electrical socket,” reports Tony Spencer, for the National Post. Vanadium-lithium batteries can offer quite a leap in efficiency over lithium-ion electric cars such as the Chevy Volt which has a pure electric range of 56 Km (35 mi) on a ten hour charge.
As these technologies develop electric cars will surely start biting away at the market share of their petrol-powered brethren. The economical development of high storage, quick recharging batteries will transform the world around us.