Green power "sand battery"

The BBC website reported on July 4 that Finnish researchers installed the world's first working "sand battery" in the town of Cancampe that can store green electricity for months at a time.

Reports on "sand batteries" were reported as early as 2014 in the Scientific Reports section of the journal Nature, titled "Extended Synthesis of Nano-Silicon for Cycling Lithium Batteries". This is a method to generate high-efficiency cathode energy through low-cost, non-toxic and environmentally friendly sand, because the sand contains quartz (SiO4), and then the sand is refined into pure silicon, which can be used as a cathode material for lithium batteries Substitutes, so sand would be of great use in batteries.

At present, the most important thing for green energy "sand batteries" in Finland is to solve the problem of comprehensive supply. The equipment uses low-grade sand, charges the heat produced by low-cost electricity from solar energy or wind energy, and then stores the heat at about 500 degrees Celsius through these sands. Finally, the home can be heated in winter when energy prices are higher.

Because most of the natural gas used in Finland comes from Russia, the war in Ukraine has brought green energy into the spotlight.

The good news is that a new piece of equipment has popped up in the corner of a small power plant in western Finland that has the potential to ease some concerns. The issue of heating and power sources is worrying politicians and citizens alike, especially given the long, cold Finnish winter ahead.

However, what are the key components of this device?

That's about 100 tons of construction sand stacked in a dark gray silo. These rough sands likely represent a simple and cost-effective way to store electricity for people to use when they need it most.

We all know that most batteries these days are made of lithium, which is expensive and can only store a limited amount of excess power. And now global climate change and the price of fossil fuels are soaring. Then new renewable energy production is particularly important. While new solar panels and wind turbines can quickly be added to the national grid, these additional sources of energy also pose significant challenges. The trickiest problem is its intermittent nature - how do you keep the lights from going out when there is no sun and no wind?

In addition to adding more renewable energy to the grid, it also means adding other energy sources to keep the grid balanced, as too much or too little electricity can cause it to collapse.

So as the grid becomes greener, there are large batteries that store energy and balance energy demand.

But in the town of Cancampe, a young team of Finnish engineers has completed the first commercial installation of sand batteries. The team believes that sand batteries could solve the storage problem in a low-cost, low-impact way.

The unit is now installed at the Vatayankoski power plant, which operates the district heating system.

The principle is to heat the sand with low-cost electricity through electrical resistance, bringing the sand to a temperature of 500 degrees Celsius. This creates hot air, which circulates through the sand through a heat exchanger.

Second, sand is an effective medium for storing heat, with little loss during long-term storage. With the research team's device, the sand can be kept at 500 degrees Celsius for months.

So when energy prices rise, the batteries release hot air that heats the water in the district heating system, which is then sent to homes, offices and even the local swimming pool.

There are still many challenges facing "sand batteries", including whether the technology can be scaled to the point where it can really make a difference, and whether developers can use the technology for power beyond heating.

No matter how big the challenge, other research institutions, such as the National Renewable Energy Laboratory, are actively looking at sand as a viable form of green battery.

In terms of technology in the new energy industry, technology is advancing, and talents must be synchronized, and battery manufacturing is inseparable from the development of talents. To make good batteries, enterprises must improve the yield rate of battery production, and the batteries produced must also be produced by aftermarket batteries. Maintenance and other issues. In the context of industry talent demand or shortage, the China Electric Power Association Battery Special Committee has also taken corresponding talent training measures.