Solar Panel Energy Storage

The sun out-powers anything that human technology could ever produce, yet solar energy only provides less than 1% of the world’s total energy. Also, the energy from the sun will never run out like other fuels. If solar panels become more efficient at converting solar rays into useful energy, then there would have to be a way to store all the extra energy that is not used when the sun is absent. Plants already have a way of turning solar energy into useful energy and storing it. This article proposes a potential solution to storing energy from a solar panel and shares research that has been conducted towards this topic.

There needs to be an effective way of storing solar energy from a solar panel to still provide energy when the sun is not shinning. There is already a living model called “the leaf” from a plant that could provide a lot of information in developing a successful way to store solar energy. The way the plant creates usable energy is through the process of photosynthesis. During photosynthesis, plants convert solar energy into chemical form by splitting water into oxygen and hydrogen.[1] The oxygen is expelled, and the hydrogen is incorporated into sugars that fuels the plant. Any unused sugar is combined into starch and will be broken down to gain energy when there is no sun. This process is performed differently by different species of pants, but have the same basic concepts. Research needs to go into a process of making solar energy into a chemical energy that can be stored in a cell. Then, just like a battery, the chemical energy that would be stored could then be turned back into electrical energy to use on days that the sun is not shinning. This would be an optimal way of storing energy from a solar panel that could then be used later when needed.

Of course there has already been some research and discovery about storing solar energy from solar panels, but there has been no major breakthrough in designs yet. In 2008, Daniel Nocera and his postdoctoral student, Matthew Kanan, discovered that cobalt can be used to create a catalyst that similarly splits water molecule in the presence of an electric current.[1] This process could form the basis of a practical solar-energy storage system, Nocera says, in which electric current from a solar cell passes through water to the catalyst, breaking the water into oxygen and hydrogen through electrolysis.[1] Those gases could be stored and later turned back into electricity in a fuel cell. It seems that this was a great start of breaking through the ice to get a good design for the process of photosynthesis for solar energy storage.

More research was found in 2011 stating, “The energy produced by solar panels can be stored in batteries or used to produce fuel that can act as storage.”[2] This fuel produced is known as solar fuel. Solar fuel processes are generally modelled on photosynthesis, the natural process whereby plants convert sunlight into chemical energy in the form of biomass and release oxygen into the atmosphere.[2] Solar fuel is the way to start looking at the chemical energy needed to be stored for later use, but there is still no process of making that chemical energy into electrical energy.

There was a good looking breakthrough with a novel solar thermal fuel, composed of azobenzene-functionalized carbon nanotubes, with the volumetric energy density of lithium-ion batteries.[3] The result being a chemical that is less expensive, and that has about 10,000 times the volumetric energy density, which means it can store more energy in less space.[4] By utilizing different methods of nano-fabrication, it is also possible to independently control both how much energy can be stored, and how long it can be stored for.[5] This method is a good way of doing exactly what the goal is for storing solar energy. One of the advantages of thermo-chemical storage in general is that the chemicals can be stored for long periods, without experiencing any energy loss.[5] This seems that this design of storing solar energy is in the process of become a success but has not been fully developed yet. The solar thermal fuel would act like the sugar that plants make for storage, but better, due to the fact that these nano-fabrications could be recharged after being used.

Plants have already had a way of producing useful energy from solar energy since they have been created. Throughout the years, researchers have made several good and advancing suggestions to get that much closer to a way to successfully store solar energy like plants do. It seems the best improvement of this technology for storing solar energy is through nano-fabrication. This seems to have been a process of stepping stones and can only get further along with finding a successful way of storing solar energy for times the sun is absent.

References

  1. S. Ornes, Plants Inspire a Better Way to Store Solar Energy, 2009.
  2. A. Pasolini, New method speeds search for solar energy storage catalysts, 2012.
  3. A. M. Kolpak and J. C. Grossman, Azobenzene-functionalized carbon nanotubes as high-energy density solar thermal fuels, Nano Lett. 11, pp. 3156–3162, 2011.
  4. B. Coxworth, New process discovered for chemically storing solar energy, 2011.

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