Amisha Yadav @CCMS Bureau
After achieving commercial viability, the solar energy sector looks at over -coming another hurdle it faces for mass adoption of the renewable energy. Solar energy was not given much attention because it was considered as infirm power which is not available during the night. But now that barrier is set to be broken with new technologies. Earlier, battery was considered as the only solution for storage. But the cost of battery and scarcity of availability have set off innovations to create alternative storage options. EarthConnect looks at these emerging technologies which can be cost- effective and used in mass scale which would be key to driving the solar revolution and reaching the Centre’s targets of having 500GW by 2030.
1 Pumped Storage Hydropower
Pumped storage hydropower (PSH) is a type of hydroelectric energy storage. It is a configuration of two water reservoirs at different elevations that can generate power as water moves down from one to the other (dis- charge), passing through a turbine. The system also requires power as it pumps water back into the upper reservoir (recharge). PSH acts similarly to a giant battery, because it can store power and then release it when needed. The Department of Energy’s “Pumped Storage Hydropower” video explains how pumped storage works.
The first known use cases of PSH were found in Italy and Switzerland in the 1890s, and PSH was first used in the United States in 1930. Now, PSH facilities can be found all around the world! According to the 2021 edition of the Hydropower Market Report, PSH currently accounts for 93% of all utility-scale energy storage in the United States. America currently has 43 PSH plants and has the potential to add enough new PSH plants to more than double its current PSH capacity.
2 Solid state batteries
Before we learn what a solid-state battery is, we need to understand how current lithium-ion technology works. Lithium-ion batteries work by letting ionic lithium cross the electrolyte barrier between the battery’s anode and cathode (the positive and negative ends). This electrolyte is a liquid in standard lithium-ion batteries.
A solid-state battery uses a solid electrolyte to regulate the lithium ions instead of a liquid one.
The main difference between a lithium-ion battery and a solid-state battery lies within the electrolyte. While lithium-ion batteries (and most other batteries) use a liquid electrolyte, solid-state batteries use a solid electrolyte. How Does A Solid State Battery Work?
Every battery has two electrodes – an anode (negative side) and a cathode (positive side). These two electrodes are made of an electrically conductive material.
Between these two electrodes (and within them) is an electrolyte containing electrically charged particles (ions). The electrolyte allows lithium ions to travel through it to combine with the anode or cathode (depending on charging or discharging). This chemical reaction permits the flow of electrical charge between the cathode and anode (through a circuit), allowing a battery to generate an electric current to power your device.
So when any device is connected to a battery, let’s say a light bulb, for example, a chemical reaction occurs between the anode, cathode, and electrolyte, creating a flow of electrical energy to power the light bulb.
A lithium-ion battery uses a liquid electrolyte to regulate the flow of current, and a solid-state battery uses a solid electrolyte.
3 Flow batteries
The renewable energy storage market is also looking at flow batteries as a promising source. It can have large-scale energy storage facilities. For many decades, research is being done on this technique. Now it has come to a stage when it can be introduced in the commercial market.
Flow battery technology is noteworthy for its unique design. Instead of a single encased battery cell where electrolyte mixes readily with conductors, the fluid is separated into two tanks and electrons flow through electrochemical cells and a membrane which separates them.
The main difference between flow batteries and other rechargeable battery types is that the aqueous electrolyte solution usually found in other batteries is not stored in the cells around the positive electrode and negative electrode. Instead, the active materials are stored in exterior tanks and pumped toward a flow cell membrane and power stack. The larger the storage tanks, the more electricity can be generated.
Power sources, such as a photovoltaic array or banks of wind turbines, charge electrons in the electrolyte solution in the positive anolyte tank connected to the anode through a process called “oxidation”.
The charged electrons are then pushed into the catholyte tank tied to the cathode through a process called “reduction”. Ion exchange occurs in half cells which sandwich the protective membrane separating the tanks.
4 What is solar skin?
For a start, imagine a solar skin as a piece of clothing for an existing solar panel. It acts not only as a decorative item but also as a shield.
Designed to camouflage into its surroundings, the printable PV sheet can support a wide range of colors and patterns. From shake-style shingles to Spanish tiles, solar panels of any style can blend seamlessly into the background with the help of solar skins.
Aside from that, users can also opt to stand out from the crowd by printing vibrant texts or artwork on their solar skins. However, the efficiency of energy generation might differ according to the complexity of the image printed.
How does solar skin work?
Essentially, a solar skin is a thin sheet of material that allows light to penetrate through it. Thus, sunrays are still able to reach the photovoltaic cells of the solar panels beneath with little to no obstruction.
However, for this to happen, these graphic overlay protectors are manufactured with a selective light filtration system that preserves up to 99% of the energy yield from natural sunlight.
This innovative solar skin technology is celebrated for its ability to allow ample sunlight to be filtered through the thin membrane while retaining its opaque property at the same time.