As the global population grows, fresh water supplies are more precious than ever. While scientists and engineers know how to purify water, making those methods sustainable and energy efficient is another question.
One promising approach is solar-driven distillation, or solar steam generation, which can help us get fresh water from wastewater or seawater. Researchers have used this method to successfully distill small batches of purified water, but they are still searching for a way to do this on a large scale.
Researchers at the University of Chicago’s Pritzker School of Molecular Engineering and UChicago-affiliated Argonne National Laboratory were part of a team that developed a pioneering new method of solar steam generation that could help bring this technology into the real world. The materials can be grown on top of wood, fabric or sponges in an easy, one-step process, and show promise for large-scale manufacturing.
“Solar steam generation techniques are still mostly focused on lab use now,” said Zijing Xia, a graduate student at Pritzker Molecular Engineering and lead author of the research. “We want to find an easy way to fabricate solar steam generators at relatively low cost.”
At the atomic scale materials can show a rich palette of dynamic behaviour, which directly affects the physical properties of these materials. For many years, it has been a dream to describe these dynamics in complex materials at various temperatures using computer simulations. Physicists of the University of Vienna have developed an on-the-fly machine-learning method that enables such calculations through direct integration into the quantum mechanics based Vienna Ab-initio Simulation Package (VASP). The versatility of the self-learning method is demonstrated by new findings, published in the journal Physical Review Letters, on the phase transitions of hybrid perovskites. These perovskites are of great scientific interest due to their potential in solar energy harvesting and other applications.
At room temperature, all materials are constantly moving at the atomic scale. Even solid rock consists of atoms that swing around. The physical properties of materials are directly linked to the arrangement of atoms in the, so called, crystal lattice. Depending on the temperature or pressure this arrangement can change thereby affecting the materials properties. One can think of diamond, which is transparent and hard because of the periodic arrangement of carbon atoms in the diamond crystal. The same atoms, arranged differently, results in black, brittle graphite. It was already possible to accurately calculate the coordinates of the atoms in simple materials at different temperatures with quantum mechanical molecular dynamics (MD) simulations. However, such calculations are computationally expensive and restrict practical applications to a couple of hundreds of atoms and limited simulation time.
This Sea Slug lives off the coast of
Japan, Indonesia and The Philippines and grazes on algae. It forms a
unique relationship with algae as it consumes the chloroplasts of its
food and then uses the chloroplasts within its own system.
photosynthesising and producing its own solar powered energy made from
the sun – just like plants. ⠀
Physicists have discovered a novel kind of nanotube that generates current in the presence of light. Devices such as optical sensors and infrared imaging chips are likely applications, which could be useful in fields such as automated transport and astronomy. In future, if the effect can be magnified and the technology scaled up, it could lead to high-efficiency solar power devices.
Working with an international team of physicists, University of Tokyo Professor Yoshihiro Iwasa was exploring possible functions of a special semiconductor nanotube when he had a lightbulb moment. He took this proverbial lightbulb (which was in reality a laser) and shone it on the nanotube to discover something enlightening. Certain wavelengths and intensities of light induced a current in the sample—this is called the photovoltaic effect. There are several photovoltaic materials, but the nature and behavior of this nanotube is cause for excitement.
“Essentially our research material generates electricity like solar panels, but in a different way,” said Iwasa. “Together with Dr. Yijin Zhang from the Max Planck Institute for Solid State Research in Germany, we demonstrated for the first time nanomaterials could overcome an obstacle that will soon limit current solar technology. For now solar panels are as good as they can be, but our technology could improve upon that.”
Energy is critical to life. However, we must work to find
solution to source sustainable energy which compliments the UK’s emission targets. This article discusses six interesting facts concerning the UK’s diversified energy
supply system and the ways it is shifting towards decarbonised alternatives.
1. In 2015, UK government announced plans to close unabated coal-fired
power plants by 2025.
A coal-fired power plant in Minnesota, US.Image: Tony Webster/Flickr
In recent years, energy generation
from coal has dropped significantly. In March 2018, Eggborough power station, North Yorkshire, closed, leaving only seven coal power plants operational in the UK. In May this
year, Britain set a record by going one week without coal power. This was the
first time since 1882!
2. Over 40% of the UK’s electricity supply comes from gas.
A natural gas search oil rig. Image: Pixabay
While it may
be a fossil fuel, natural gas releases less carbon dioxide emissions compared
to that of coal and oil upon combustion. However, without mechanisms in place
to capture and store said carbon dioxide it is still a carbon intensive energy
3. Nuclear power accounts for approximately 8% of UK energy supply.
generation is considered a low-carbon process. In 2025, Hinkley Point C nuclear
power-plant is scheduled to open in Somerset. With an electricity generation
capacity of 3.2GW, it is considerably bigger than a typical power-plant.
In 2018, the
total installed capacity of UK renewables increased by 9.7% from the previous
year. Out of this, wind power, solar power and plant biomass accounted for
4. The Irish Sea is home to the world’s largest
wind farm, Walney Extension.
The Walney offshore wind farm.Image: Wikimedia Commons
to this, the UK has the third highest total installed wind capacity across
Europe. The World Energy Council define an ‘ideal’ wind farm as one which experiences
wind speed of over 6.9 metres per second at a height of 80m above ground.
As can be seen in the image below, at 100m, the UK is well suited for wind
5. Solar power accounted for 29.5% of total renewable electricity capacity
This was an
increase of 12% from the previous year (2017) and the highest amount to date! Such
growth in solar power can be attributed to considerable technology cost
reductions and greater average sunlight hours, which increased by up to 0.6
hours per day in 2018.
Currently, the intermittent
availability of both solar and wind energy means that fossil fuel reserves are
required to balance supply and demand as they can run continuously and are
easier to control.
2018, total UK electricity generation from bioenergy accounted for
approximately 32% of all renewable generation.
A biofuel plant in Germany.
This was the
largest share of renewable generation per source and increased by 12% from the
previous year. As a result of Lynemouth power station, Northumberland, and another unit at Drax, Yorkshire, being converted from fossil fuels to biomass, there was a large increase in
plant biomass capacity from 2017.
Reace Edwards is a member of SCI’s Energy group and a PhD Chemical Engineering student at the University of Chester. Read more about her involvement with SCI here or watch her recent TEDx Talk here.
The rose may be one of the most iconic symbols of the fragility of love in popular culture, but now the flower could hold more than just symbolic value. A new device for collecting and purifying water, developed at The University of Texas at Austin, was inspired by a rose and, while more engineered than enchanted, is a dramatic improvement on current methods. Each flower-like structure costs less than 2 cents and can produce more than half a gallon of water per hour per square meter.
A team led by associate professor Donglei (Emma) Fan in the Cockrell School of Engineering’s Walker Department of Mechanical Engineering developed a new approach to solar steaming for water production – a technique that uses energy from sunlight to separate salt and other impurities from water through evaporation.
In a paper published in the most recent issue of the journal Advanced Materials, the authors outline how an origami rose provided the inspiration for developing a new kind of solar-steaming system made from layered, black paper sheets shaped into petals. Attached to a stem-like tube that collects untreated water from any water source, the 3D rose shape makes it easier for the structure to collect and retain more liquid.
Capturing and manipulating light at nanoscale is a key factor to build high efficiency solar cells. Researchers in the 3-D Photovoltaics group have recently presented a promising new design. Their simulations show that vertically stacked nanowires on top of ultrathin silicon films reduces the total amount of material needed by 90 percent while increasing the efficiency of the solar cell. These promising simulation results are an important step toward next-generation solar cells. The results have been published on May 23rd in Optics Express.
A strategy to reduce cost and rigidity of photovoltaics is to combine ultrathin silicon photovoltaic films with semiconductor nanowire solar cells. The mechanical flexibility and resilience of micrometer thin cells make them well suited to apply on curved surfaces.
The idea is to optically couple the two materials stacked on top of each other as a tandem cell: a gallium arsenide (GaAs) nanowire array on top of an ultrathin silicon (2um-thick) film. GaAs vertical nanowires are well-known semiconductor components in photovoltaic applications.
Engineers at the University of California San Diego have developed a high-throughput computational method to design new materials for next generation solar cells and LEDs. Their approach generated 13 new material candidates for solar cells and 23 new candidates for LEDs. Calculations predicted that these materials, called hybrid halide semiconductors, would be stable and exhibit excellent optoelectronic properties.
The team published their findings on May 22, 2019 in the journal Energy & Environmental Science.
Hybrid halide semiconductors are materials that consist of an inorganic framework housing organic cations. They show unique material properties that are not found in organic or inorganic materials alone.
A subclass of these materials, called hybrid halide perovskites, have attracted a lot of attention as promising materials for next generation solar cells and LED devices because of their exceptional optoelectronic properties and inexpensive fabrication costs. However, hybrid perovskites are not very stable and contain lead, making them unsuitable for commercial devices.
The most affordable, efficient way to harness the cleanest, most abundant renewable energy source in the world is one step closer to reality.
The University of Toledo physicist pushing the performance of solar cells to levels never before reached made a significant breakthrough in the chemical formula and process to make the new material.
Working in collaboration with the U.S. Department of Energy’s National Renewable Energy Lab and the University of Colorado, Dr. Yanfa Yan, UToledo professor of physics, envisions the ultra-high efficiency material called a tandem perovskite solar cell will be ready to debut in full-sized solar panels in the consumer market in the near future.
Perovskites, compound materials with a special crystal structure formed through chemistry, would replace silicon, which – for now – remains the solar-cell material of choice for converting the sun’s light into electrical energy.
Tiny light-emitting microalgae, found in the ocean, could hold the secret to the next generation of organic solar cells, according to new research carried out at the Universities of Birmingham and Utrecht.
Microalgae are probably the oldest surviving living organisms on the planet. They have evolved over billions of years to possess light harvesting systems that are up to 95 per cent efficient. This enables them to survive in the most extreme environments, and adapt to changes our world has seen over this time-span.
Unravelling how this system works could yield important clues about how it could be used or recreated for use in new, super-efficient organic solar panels. Because of the complexity of the organisms and the huge variety of different species, however, progress in this area has been limited.
The team made use of some of the advanced methods of a technique called mass spectrometry, which enabled them to characterize individual components of the algae light-harvesting system. This approach enabled them to reveal details of distinct modules of the system that have never been seen before. This fine detail will help scientists understand why microalgae are so efficient at light harvesting.