March 23, 2017 | Leave a Comment
A University of Cambridge team of scientists has developed a way of using solar power to generate hydrogen that is both sustainable and relatively low cost. It simply uses natural light to generate hydrogen from biomass.
Dr. Moritz Kuehnel, from the Department of Chemistry at the University of Cambridge, joint lead author on a new research paper published in Nature Energy, said, “Lignocellulose is nature’s equivalent to armored concrete. It consists of strong, highly crystalline cellulose fibers, that are interwoven with lignin and hemicellulose which act as a glue. This rigid structure has evolved to give plants and trees mechanical stability and protect them from degradation, and makes chemical utilization of lignocellulose so challenging.”
Biomass has been a source of heat and energy since the beginning of recorded history. The planet’s oil reserves are derived from ancient biomass which has been subjected to high pressures and temperatures over millions of years. Lignocellulose is the main component of plant biomass and up to now its conversion into hydrogen has only been achieved through a gasification process which uses high temperatures to decompose it fully.
The Cambridge chemists’ new technology relies on a simple photocatalytic conversion process. Catalytic nanoparticles are added to alkaline water in which the biomass is suspended. This is then placed in front of a light in the lab which mimics solar light. The solution is ideal for absorbing this light and converting the biomass into gaseous hydrogen which can then be collected from the headspace. The hydrogen is free of fuel-cell inhibitors, such as carbon monoxide, which allows it to be used for fuel.
The nanoparticle is able to absorb energy from solar light and use it to undertake complex chemical reactions. In this case, it rearranges the atoms in the water and biomass to form hydrogen fuel and other organic chemicals, such as formic acid and carbonate.
Joint lead author, Dr David Wakerley, also of the Department of Chemistry, said, “There’s a lot of chemical energy stored in raw biomass, but it’s unrefined, so you can’t expect it to work in complicated machinery, such as a car engine. Our system is able to convert the long, messy structures that make up biomass into hydrogen gas, which is much more useful. We have specifically designed a combination of catalyst and solution that allows this transformation to occur using sunlight as a source of energy. With this in place we can simply add organic matter to the system and then, provided it’s a sunny day, produce hydrogen fuel.”
The team used different types of biomass in their experiments. Pieces of wood, paper and leaves were placed in test tubes and exposed to solar light. The biomass didn’t require any processing beforehand.
The technology was developed in the Christian Doppler Laboratory for Sustainable SynGas Chemistry at the University of Cambridge. The head of the laboratory, Dr. Erwin Reisner, added, “Our sunlight-powered technology is exciting as it enables the production of clean hydrogen from unprocessed biomass under ambient conditions. We see it as a new and viable alternative to high temperature gasification and other renewable means of hydrogen production.”
Dr. Reisner summed up saying, “Future development can be envisioned at any scale, from small scale devices for off-grid applications to industrial-scale plants, and we are currently exploring a range of potential commercial options.”
One of the challenges facing modern society is what it does with its waste products. As natural resources decline in abundance, using waste for energy is becoming more pressing for both governments and business.
This technology sounds pretty good. No power source needed, just sunlight and inevitably some prep work on the feedstock. There is the matter of the alkaline water that would need handled more carefully than fresh water, but we aren’t informed as to how strong is the alkalinity. And naturally what are the circumstances of the waste material?
There is a huge supply of biomass, both unused and used. We need more data. What will a square meter of sunlit processing accomplish? How does one get the nanoparticles back? Congratulation are in order along with a bunch of encouragement.
March 22, 2017 | Leave a Comment
American Technion Society researchers have developed a new method for safely and efficiently producing hydrogen using separate cells for the hydrogen and oxygen. The new technology is expected to significantly reduce the cost of producing the hydrogen and shipping it to the customer.
The researchers at Technion are developing a photoelectrochemical (PEC) cell that utilizes solar energy to split water into hydrogen and oxygen directly, without the need for an external power source.
The team set out to solve three major hydrogen challenges: Keeping the hydrogen and the oxygen separate from each other, collecting the hydrogen from millions of PEC cells, and transporting the hydrogen to the point of sale.
The Technion team solved these challenges by developing a new method for PEC water splitting. With this method, the hydrogen and oxygen are formed in two separate cells – one that produces hydrogen, and another that produces oxygen. This is in contrast to the conventional method, in which the hydrogen and oxygen are produced within the same cell, and separated by a thin membrane that prevents them from intermixing and forming a flammable and explosive mixture.
The new process allows geographic separation between the solar farm consisting of millions of PEC cells that produce oxygen exclusively, and the site where the hydrogen is produced in a centralized, cost-effective and efficient manner. They accomplished this with a pair of auxiliary electrodes made of nickel hydroxide, an inexpensive material used in rechargeable batteries, and a metal wire connecting them.
Avigail Landman, a doctoral student in the Nancy & Stephen Grand Technion Energy Program explained, “In the present article, ‘Photoelectrochemical Water Splitting In Separate Oxygen and Hydrogen Cells’ published in Nature Materials, we describe a new method for producing hydrogen through the physical separation of hydrogen production and oxygen production. According to our cost estimate, our method could successfully compete with existing water splitting methods and serve as a cheap and safe platform for the production of hydrogen.”
This is not the whole of the technology, as noted previously, the vision of the Technion researchers is geographic separation between the sites where the oxygen and hydrogen are produced: at one site, there will be a solar farm that will collect the sun’s energy and produce oxygen, while hydrogen is produced in a centralized manner at another site, miles away.
Thus, instead of transporting compressed hydrogen from the production site to the sales point, it will only be necessary to swap the auxiliary electrodes between the two sites. Economic calculations performed in collaboration with research fellows from Evonik Creavis GmbH and the Institute of Solar Research at the German Aerospace Center, indicate the potential for significant savings in the setup and operating costs of hydrogen production.
In October, Ms. Landman won first place in the energy category in the Three Minute Thesis competition held in Australia. At the competition, held on the initiative of the University of Queensland, participants are required to present groundbreaking research in just three minutes. Watch Ms. Landman’s presentation below:
The method developed at the Technion for separating hydrogen production and oxygen production was the basis for the development of new two-stage electrolysis technology. This technology, which was developed by Dr. Hen Dotan from the Electrochemical Materials & Devices Lab, enables hydrogen production at high pressure and with unprecedented efficiency, thus significantly reducing hydrogen production costs. The new technology is now in its pre-industrial development stage.
This is highly interesting concept that is reported to be working. If the electrodes are holding a comparably large store of hydrogen and the release can be regulated, this team may be on to something huge. Perhaps the electrodes themselves can be sold / exchanged and used as fuel canisters that consumers can defuel as needed, The possibilities are awe inspiring!
A range of technology minerals, which are an essential ingredient in everything from laptops and cell phones to hybrid or electric cars to solar panels and copper wiring for homes are going to become in short supply. Additionally, base metals like copper are also a matter of immense concern.
An international team of researchers, led by the University of Delaware’s (UD) Saleem Ali, says global resource governance and sharing of geoscience data is needed to address challenges facing our future mineral supply.
The research team, which included experts from academic, government and industrial institutions across five continents, the U.S., Europe, South Africa, Australia and South America, reported their findings last week in a peer-reviewed paper published in Nature.
Ali, the paper’s lead author and Blue and Gold Distinguished Professor of Energy and Environment at UD said, “There are treaties on climate change, biodiversity, migratory species and even waste management of organic chemicals, but there is no international mechanism to govern how mineral supply should be coordinated.”
The researchers reviewed data and demand forecasts on the sustainability of global mineral supplies in coming decades. The study showed that mining exploration is not keeping up with future demand for minerals and recycling in and of itself would not be able to meet the demand either.
At the same time, transitioning to a low carbon society will require vast amounts of metals and minerals to manufacture clean technologies and the researchers say society is not equipped to meet the additional needs for these raw materials.
According to the research team, international coordination is needed on where to focus exploration investment efforts, what kind of minerals are likely to be found in different locations and hence, what kind of bilateral agreements are needed between various countries.
Global population numbers are expected to reach 8.5 billion by 2030, the target date for the United Nations sustainable development goals, meaning even more consumers in the marketplace.
The largest percentage of investment in a mineral for exploration is in gold, which although highly profitable, is largely used for jewelry.
Major commodity metals like iron ore, copper and gold (and other precious metals) are sold on a global market the way that oil is sold. Rare earth metals and other technology minerals, however, are sold through individual dealers and with large price variations.
For goods like clothing, cosmetics or electronics, price can easily trigger changes in supply. This is not possible with mineral supply, because the time horizon for developing a rare earth mineral deposit from exploration and discovery to mining is 10-15 years.
For a recent example, the last major deposit for copper was discovered in Mongolia 15 years ago and only began producing in the fall of 2016, creating huge supply challenges.
Consider this, too, only 10 percent of early exploration efforts actually lead to a mine able deposit. Most discoveries are either not economically viable to mine or companies run into land use or zoning problems due to geopolitical challenges. Known often as “Not In My Backyard!”
Ali also added, “Countries where minerals are likely to be found may have poor governance, making it higher risk for supply. But production from these countries will be needed to meet global demand. We need to be thinking about this.”
Then there is the common consumer misconception that we can just use something else. For many mineral uses, there are no alternatives. There are few commercially viable replacement minerals for many applications of copper wiring, for example.
The same may be true for technology metals that could become essential in green technologies – like neodymium, terbium or iridium. These minerals are only needed in small quantities, but they are indispensable to making the technology work, meaning that while the scale seems small, the value is immense.
Environmental costs and materials recycling options need to be considered, too.
Metals and carbon fiber used in the manufacture of aircraft or automobiles are often thought to have less environmental impact because they are light, but Ali explained that the manufacturing of carbon fibers currently is highly petroleum based.
“Because they are lighter, people think they are somehow greener, but they aren’t and they are difficult, if not impossible, to recycle,” he said.
Ali and his colleagues hope that this paper is the first step toward an intergovernmental mechanism or other solution that can empower nations to plan for mineral scarcity as both the public and private sector are mineral dependent.
The research team contends that positive strides can be made quickly through expansion of developing organizations, such as the United Nation’s International Resource Panel or the Canadian-led Intergovernmental Panel on Mining Metals and Sustainable Development.
Longer term solutions will require greater transparency among nations, and could include global sharing of geological data and the creation of mechanisms to protect mineral deposit ‘finds’ much like we protect intellectual property.
“It’s about managing the flow of resources from the ground to product to consumer to recycling,” Ali said.
The hard truth, though, is that if nothing changes shrinking supply naturally will lead to rising prices. It also could lead to serious global challenges if essential resources that people have been so dependent on collapse.
Take the infrastructure around renewable energy technologies, such as wind turbines. Right now, the technology is new, but what if resources dry up for new production or repair of existing technology? A bottleneck in terms of material production could create a bottleneck in terms of energy production too.
Even nuclear power, often considered a universal cure for global energy woes, is not immune to mineral scarcity. In fact, all nuclear reactors today require uranium – a metal that must be mined – in order to function. There seem to be no thorium mines at all.
“People have been so concerned about climate change that it’s created a real movement around it. We don’t see this around resource use and recovery, even though it is much closer to us on a daily basis,” Ali said.
If any point of the team’s work is worthwhile its pointing out that metal production is no where close to being regarded as important as it actually is. All the hope that government getting involved may not get to the result the team hopes for, it may actually slow down the market forces driving to a deeper and longer shortage.
The other noteworthy point is the comparison with climate change. Folks are easily manipulated enmass, with the climate industry showing just how effective fear mongering can be.
There is a lot of evidence the crisis is well underway. One of the most common crimes now-a-days is copper and metal thieving. We won’t be able to honestly say we didn’t see this coming . . .
VTT Technical Research Center of Finland and German company ZAE Bayern have built a pilot system emission-free, solar-powered chiller. Demand and the need for cooling are growing, the potential market is world-wide, particularly in warm countries.
VTT and ZAE Bayern have developed a solar-powered 10 kW chiller. This absorption chiller works in the same way as the gas refrigerators used in Finnish holiday cabins, for example. But in this case, a solar thermal collector is used instead of gas. The method requires electricity for the flow pumps only. If necessary, the chiller can also serve as a heat pump.
The results of the project showed that – to be used as a heating pump as well – an economically viable and competitive, solar-powered absorption chiller would need to be 50 kW or bigger.
Finnish company Savo-Solar Plc participated in both the planning phase and the practical tests. As a result, the company’s head office was successfully cooled using the pilot system built for the project. Savo-Solar and ZAE Bayern aim to develop a commercial product which enables users to cut their electricity bills through cooling with absolutely no need for electricity.
The chiller was tested as an air-conditioner for Savo-Solar’s office during the summer and for heating it during the winter. Solar collectors on the roof of the building were used to collect the required energy. If the collectors did not produce enough energy during, say, the winter, or on a cloudy day, a heat pump served as a substitute energy source. Other possible energy sources would be district heating, biofuel boilers or industrial process heat. Examples of large, megawatt-class absorption chillers based on district heating can already be found in Helsinki and Turku in Finland.
Another practical test was performed using an absorption chiller based on a bio-boiler in ZAE Bayern’s laboratory in Munich, Germany. This also is a system that can be supplemented with solar energy.
The project began in October 2013 and ended at the turn of last year running 39 months. It was funded by: Savo-Solar Plc, Tekes – the Finnish Funding Agency for Innovation, and the German Federal Ministry of Economics and Technology (BMWi).
Considering the electrical power grid mess that Germany has voted itself into, this kind of project has intense interest. The idea that cooling and heating can be nearly electricity free has an immense attraction when the power grid costs ratepayers incredible sums compared to any other industrialized country.
But does it really work? Its a compact absorption chiller comprising hydraulic rack absorption machines that transform heat into cold by means of a sorption process between a refrigerant (e.g. Water) and a Sorbent (e.g. Lithium bromide) and can be used as a chiller or heat pump. In contrast to conventional vapor compression chillers/heat pumps, the required electricity consumption is almost negligible. Yes, it works. Keep in mind, it always needs a heat source. You’re going to need some saved heat to air condition over night.
What’s missing for the rest of the world is the initial cost estimates and the longevity expectation. With Germans shelling out double and triple U.S. electricity rates the calculations start from very different inputs. What isn’t real clear is the amount of solar paneling needed to harvest heat.
This technology will find some market. Its too soon for information that may apply to the rest of the world. There is also a lithium component, a not so inexpensive item. Unless batteries get far smaller and higher capacity lithium will continue to be rather expensive.
Still for a huge part of the world this technology has great appeal. Low cost cooling where air conditioning is a major part of household expense is going to have some market legs.
Georgia Institute of Technology materials researchers have created a nanofiber that could help enable the next generation of rechargeable batteries and increase the efficiency of hydrogen production from water electrolysis.
In a study published in Nature Communications and sponsored by the National Science Foundation, the researchers describe the development of double perovskite nanofiber that can be used as a highly efficient catalyst in ultrafast oxygen evolution reactions. The ultrafast oxygen evolution reactions are one of the underlying electrochemical processes in hydrogen-based energy and the newer metal-air batteries.
Meilin Liu, a Regents Professor in the Georgia Tech School of Materials Science and Engineering explained, “Metal-air batteries, such as those that could power electric vehicles in the future, are able to store a lot of energy in a much smaller space than current batteries. The problem is that the batteries lack a cost-efficient catalyst to improve their efficiency. This new catalyst will improve that process.”
Perovskite refers to the crystal structure of the catalyst the researchers used to form the nanofibers. “This unique crystal structure and the composition are vital to enabling better activity and durability for the application,” Liu said.
During the synthetization process, the researchers used a technique called composition tuning – or “co-doping” – to improve the intrinsic activity of the catalyst by approximately 4.7 times. The perovskite oxide fiber made during the electrospinning process was about 20 nanometers in diameter, which thus far is the thinnest diameter reported for electrospun perovskite oxide nanofibers.
The researchers found that the new substance showed markedly enhanced oxygen evolution reaction capability when compared to existing catalysts. The new nanofiber’s mass-normalized catalytic activity improved about 72 times greater than the initial powder catalyst, and 2.5 times greater than iridium oxide, which is considered a state of the art catalyst by current standards.
That increase in catalytic activity comes in part from the larger surface area achieved with nanofibers, the researchers said. Synthesizing the perovskite structure into a nanofiber also boosted its intrinsic activity, which also improved how efficiently it worked as a catalyst for oxygen evolution reactions (OER).
In the study paper’s introduction the researchers said, “This work not only represents an advancement in the development of highly efficient and durable electrocatalysts for OER but may also provide insight into the effect of nanostructures on the intrinsic OER activity.”
Beyond its applicability in the development of rechargeable metal air batteries, the new catalyst could also represent the next step in creating more efficient fuel cell technologies that could aid in the creation of renewable energy systems.
Liu said, “Solar, wind, geothermal, those are becoming very inexpensive today. But the trouble is those renewable energies are intermittent in nature. When there is no wind, you have no power. But what if we could store the energy from the sun or the wind when there’s an excess supply. We can use that extra electricity to produce hydrogen and store that energy for use when we need it.”
That’s where the new nanofiber catalysts could make a difference, he said.
“To store that energy, batteries are still very expensive,” Liu said. “We need a good catalyst in order for the water electrolysis to be efficient. This catalyst can speed up electrochemical reactions in water splitting or metal air batteries.”
Those are spectacular numbers. Lets hope the replicators can duplicate or exceed the Georgia results. This could be revolutionary technology in three fields: oxygen reduction, batteries and fuel cells. On wonders what innovations on this discovery will do. Congratulations to this extraordinary team!