Tag Archives: concentrated solar

Innovative solar energy on the horizon

Solar technology is emerging on all fronts.

Some critics find solar energy limiting, due to its bulkiness and intermittence. But revolutionary solar technology will challenge arguments against the use of solar as renewable energy. Look below for a list of existing solar technology and what it may become in the future.

 

  1. Solar photovoltaic (PV)

The sparkly solar panels you see on the rooftops of homes are typically solar PV. These panels work by converting light into electricity, known as the PV effect. Silicon is the element most commonly used in solar PV due to its abundance on earth and relative affordability.

Alex Wilhelm, founder and president of United Solar Initiative, works to install solar PV in rural regions of Nicaragua. He recognizes the benefit of the off-grid nature of solar PV in low-income communities.

“Accompanied with battery storage, solar panels enable communities to remain sustainable off the grid and are the simplest form of renewable electricity to install,” he said.

As opposed to developing countries, solar PV will likely be concentrated at the utility and commercial level in more developed nations.

Solar PV installed on a rooftop. (Photo by U.S. Army)
Solar PV installed on a rooftop. (Photo by U.S. Army)

 

  1. Thin film PV

As its name suggests, thin film PV is extremely thin—only one micron thick. To put that into perspective, human hair is about 75 microns. This makes thin film more lightweight and versatile than solar PV, and suitable for many surfaces, from rooftop shingles to clothing.

Thin film works similarly to solar PV, by converting photons into electricity. However, thin film cells can be made from three different elements: amorphous silicon, cadmium telluride, and copper indium gallium deselenide. Each of these elements has advantages and disadvantages and is being tested for viability.

Thin film solar used as shingles on a roof. (Photo by Tai Viinikka)
Thin film solar used as shingles on a roof. (Photo by Tai Viinikka)

 

3. Concentrated solar power (CSP)

Concentrated solar uses mirrors to direct sunlight to a central point, which heats a liquid and powers steam turbines to create electricity. These plants are large in size, which makes the desert a desirable location for them. Unfortunately, this technology has high upfront costs and requires access to water, which creates a catch-22 situation when locating plants in the desert.

The largest benefit of CSP is its ability to generate electricity overnight and store energy in the form of thermal energy.

Mirrors used for concentrated solar power. (Photo by Alex Lang)
Mirrors used for concentrated solar power. (Photo by Alex Lang)

 

  1. Perovskite solar cells

This type of solar technology is made from a particular compound that is usually made out of lead or tin. Perovskite solar cells were first created in the early 2010s, but have already achieved efficiency on par with thin film.

Dr. Wei You, a chemistry professor at UNC-Chapel Hill, noted two main issues with perovskite: the use of lead to construct them and their stability. He said perovskite cells tend to get easily damaged by water, which is a big waste of money and energy. He thinks stability is their biggest barrier, and that their efficiency will likely remain at 21 percent going forward.

Perovskite solar cells. (Photo by University of Oxford Press Office)
Perovskite solar cells. (Photo by University of Oxford Press Office)

 

5. Organic solar cells

Organic PV aims to provide energy that is abundant on earth, and potentially cheaper than other solar solutions. This technology uses non-toxic light-absorbing materials (dyes) and plastics instead of elements like silicon, which are found in traditional PV.

This type of solar is attractive because of its ability to do things that silicon solar cells can’t, such as being integrated into transparent surfaces, like windows.

You has studied organic solar for over 10 years.

“From 2005 to 2012 we were able to push efficiency from 5 percent to 10 percent,” he said.

You’s research team has achieved organic solar cells with 12 percent efficiency. While this is only half as efficient as silicon, You is hopeful that the efficiency and longevity of organic solar will continue rising, and increase in market share in the next decade.

Organic solar cell. (Photo by KIC InnoEnergy)
Organic solar cell. (Photo by KIC InnoEnergy)

 

  1. Quantum dots

Unlike traditional solar cells, quantum dots have the ability to absorb light from non-visible parts of the light spectrum. This makes quantum dots capable of absorbing energy all day, which refutes the argument that solar energy only works when the sun is shining.

Another unique feature of quantum dots is its potential to become “spray-on,” which would allow nearly any surface to create solar energy. There is also potential for quantum dots to be the most efficient solar technology yet.

Quantum dots range in color depending on size and the light they absorb. (Photo by Antipoff)
Quantum dots range in color depending on size and the light they absorb. (Photo by Antipoff)