It’s no secret everyone has been affected by COVID-19. And unfortunately it's impacted our energy sources around the world. As we progress through these uncertain times and look to rebuild our economy, renewable energy has been given an even greater platform to showcase its possibilities.Continue reading →
Microclimate is a buzzword you may have heard in conversations around air pollution, climate change and renewable energy. But what is exactly, and how can we use it?Continue reading →
Over the last few weeks we’ve discussed some of the most popular sources of renewable energy: Wind and Hydro.
Solar power, specifically photovoltaic power, has been key to clean energy in the last 30 years. These thin material systems rank 3rd in global energy capacity, and will continue to contribute in growing renewable efforts.
Rise to Power
Photovoltaic energy is extracted from semiconductors that convert energy from UV rays into electricity. These devices, often referred to as PV devices, can power anything from a cell phone to large businesses.
Alexandre Edmund Becquerel introduced the idea of photovoltaic energy in the 1800s. Increased experimentation carried well into the 20th century and evolved into a viable energy source by the 50s.
Falling only third behind wind and hydro, PV energy is predicted to become the most widely used source of alternative electricity. Since the 90s, photovoltaic systems have been used in small applications. In 2000, Germany piloted its first mass market project roofing 1,000 homes in photovoltaic devices.
Over time, production and installation prices have fallen significantly, making PV systems more attainable to home and business owners alike. Though PV devices only account for less than 5% of global energy sources, considerable growth is imminent.
From new innovations to real-life implementation, photovoltaic systems are leading the way in renewable energy. As this type of solar power grows in mass production, scientists are actively searching for ways to create more effective and inexpensive devices.
Here are some of the latest advancements.
Thin Film Materials
The most popular PV system is a thin film model that’s relatively cheaper to produce. Silicon based materials have dominated the market and experiments for years. Its cost effective appeal has made it a popular choice for larger operations.
A team of physicists at the University of Buffalo recently created a new thin film made of nontoxic barium zirconium sulfide. It's just as cost effective but has a greater energy output potential. This discovery has introduced new possibilities for semiconductor materials and a new wave of PV devices.
Power in Transparency
In 2012, researchers at UCLA developed a double layer photovoltaic device intended for windows, sunroofs, etc. This model was made of crystalline silicon and wasn’t fully transparent, boasting a reddish hue. While not completely practical for its intended applications, it paved the way for further advancements.
In 2019, scientists in Korea modified this experiment by adding perfectly placed holes in the film creating a “transparent” appearance to the naked eye. This model still possessed a slight coloration, but was significantly less than the original material.
Currently, renewable power accounts for almost 45% of Brazil’s primary power. The country uses hydropower to supply approximately 80% of its electricity, and intends to use PV plants to fill the gap.
Brazil’s Sao Goncalo solar PV plant holds the largest photovoltaic system in South America, generating more than 1,200 gigawatts per hour. The system has been running since early 2020, and gives promise to those looking for sustainable energy at large.
Low cost materials and reasonable installation prices make PV systems an ideal technology for renewable energy. Photovoltaic energy will be the growth driver in global renewable energy in the years to come.
It’s easy to imagine sun and wind energy. We’ve seen the solar panelling on rooftops and wind turbines in vast fields. Yet, what happens when there’s not enough sunshine or wind to generate power? Those energy sources become obsolete, and people resort to traditional methods.
We’re not saying these aren’t solid energy sources, but they do have limitations hinged upon weather patterns and eco systems.
Ocean energy harvesting is bringing a new wave of renewable power. Pun intended.
Space exploration is a topic that has piqued the world’s interest since Apollo landed on the moon in the 60s. There are so many questions around space travel, the preparation, mission details and much more. But have you ever asked yourself how these missions are powered?
Lucky for you, we’ve just become resident experts in powering spacecrafts. Missions, past and future, have been made possible through the use of radioisotope thermoelectric technology - an incredible source of energy responsible for powering the most historic voyages of our time.
With climate change posing an increasing threat to our environment, scientists believe pressure in thermoelectric generators and thermionic emissions could be the solution.
These alternative energy sources have provided renewable power by recycling “wasted” heat. Examples of this technology are found in gas pipelines and spacecraft. While this has contributed a sizable reduction in the nation’s energy budget, it still hasn’t reached its full potential. The flaw in current thermoelectric compounds is that it only truly succeeds at high heat. Better performance at room temperature is actually the most critical form of renewable energy, but that hasn’t seen improvement in 60 years.
Scientist Liu-Cheng Chen hypothesized that combining pressure and charged chromium particles with lead selenide would produce this greater form of thermoelectric energy. He proved his theory by placing the lead selenide under 30x greater the normal atmospheric pressure. This caused certain changes at the atomic level and produced the most efficient level of room temp thermoelectric generation to date.
Another example of this groundbreaking discovery is thermionic emission of graphene. Thermionic emission happens when a metal is heated and electrons are shot out of the surface. Historically, these emissions have been used to power vacuums and has been experimented with heavily. Emissions from graphene are especially unique because the material is a nanomaterial that’s atomically thin, making it an unusual candidate for this type of energy generation.
Researchers at Singapore University of Technology and Design have created a new general framework to capture thermionic emissions in graphene. Undergrad student, Yueyi Chin, stated that traditional methods of recording this energy can be up to 50% inaccurate! This new theoretical framework helps decrease that inaccuracy by accounting for graphene’s reaction at higher energy states. The electronic properties of graphene are no longer the mystery it used to be. With this new thermionic emission model, we can better see the potential of graphene materials and devices.
Graphene thermionic emissions and pressurized materials will enable scientists to further experiment ways to create renewable energy and reduce our carbon footprint.
We’re all familiar with solar panels. How they absorb light that can power just about anything. But what if we told you energy can now be harvested in the dark.
UCLA scientist, Dr. Aaswath Raman, explored this idea of turning darkness to light after traveling through a village in Sierra Leone with no access to power at night. He hypothesized that coupling cool, dark air from space and natural heat flowing under a platform could generate enough energy to power a light bulb.
This theory is supported by the radiative cooling principle - objects radiate heat absorbed during the day into space at night. Radiative cooling also explains why you may see morning frost on the ground. The temperature difference between the exposed surface and the air beneath creates electricity.
Raman collaborated with scientists from Stanford University to test his theory using this principle. Together they created a thermoelectric generator comprised of styrofoam wrapped in aluminum, a metal disc painted black, a voltage convertor, and an LED light bulb. They placed the homemade model on a roof and monitored its electrical output for 6 hours. Not only did it power the light bulb, it generated 25 mW/m2.
While this experiment was minimal impact, it demonstrated three important things:
Soldiers depend on the battery life in their electronic devices like radios, GPS systems, night vision goggles while out on a mission. According to Noel Soto, project engineer at the Army Natick Soldier Research, Development, and Engineering Center, studies have shown that 16 to 20 pounds of the heavy loads soldiers carry comes from batteries.
"While the standard resupply mission is currently 72 hours, military operations are becoming increasingly expeditionary -- often with a special-ops focus -- pushing resupply missions out to five or more days," said Edward Plichta, Command, Power and Integration Directorate's Chief Scientist for Power & Energy, under the Communications-Electronics Research, Development and Engineering Center.
To remedy issues like this, the army has been focused on finding alternative ways to power gear. In 2016, the army began testing a device that straps to Soldiers’ legs and generates power just by walking. The device, now called The Power Walk®, is a lightweight energy harvester that generates electricity walking, much like how regenerative braking works in hybrid cars. The harvester’s on-board microprocessors analyze the wearer’s gait to determine when to generate maximum power with the least amount of effort.
Other energy-harvesting innovations, like the Energy Harvester Assault Pack, reuse the energy exerted naturally from Soldiers’ movements. Not only is this reusable energy guaranteed to have a protracted battery life, but it also frees up space in Soldiers’ bags, lightening their loads and allowing more room for necessities like water, food, and ammunition.
The next phase of the energy harvesting development focuses on creating and providing power beyond just charging batteries. Accomplishing this could mean that power can be provided to all Soldier-wearable devices, like the Product Manager Soldier Warrior's NETT Warrior device, through a Soldier power management system.
Valuable innovations like these are created to benefit our Soldiers so they not only have to carry the weight of batteries, but also so they can extend their mission with the same battery. With improvements in technological innovations, the possibilities of helping our Soldiers are endless.
II-VI Marlows’ team of accomplished engineers works hand-in-hand with OEMs to develop optimized thermal solutions. From concept to completion, II-VI Marlow offers state-of-the-art thermoelectric solutions to meet your requirements.