Recent research has used ceramic metal plates to conduct heat at higher temperatures and pressures to improve solar power generation efficiency.
Recently, American scientists have developed a new material and manufacturing process that uses solar energy as thermal energy to generate electricity more efficiently.
In addition to using power generation and power storage during cloudy and night times, solar power is a lower-cost energy solution. However, solar power only accounts for 2% of US power sources. A research team from Purdue University in the United States has developed a new material and manufacturing process that makes the use of solar energy (ie, thermal energy) to generate electricity more efficient and feasible.
This technological innovation is an important link in the direct competition between solar power generation and fossil fuel power generation. At present, fossil fuel power generation accounts for more than 60% of the total power generation in the United States. Kenneth Sandhage, a professor of materials engineering at Purdue University, said: "Storing solar energy in the form of thermal energy is cheaper than storing energy in the form of batteries, so the next step is to reduce the cost of solar power generation while reducing greenhouse gas emissions."
The research was done in collaboration with Georgia Institute of Technology, the University of Wisconsin-Madison, and Oak Ridge National Laboratory, and was published in the recently published journal Nature.
The use of solar energy is not only to obtain thermal power through solar panels on the farm or on the roof, but people can also use solar thermal energy to focus on power generation. Centralized solar power stations use a mirror or lens to gather a large amount of light in a small area, thereby converting solar energy into electricity, and the heat generated is transferred to the molten salt. The heat of the molten salt is then transferred to a "working fluid", supercritical carbon dioxide, which expands and causes the turbine to rotate to generate electricity during work.
In order to effectively reduce the cost of solar power generation, a turbine engine needs to generate more electricity with the same heat, which means it runs hotter. The technical bottleneck of this process is the heat exchanger, which transfers the heat of the hot molten salt to the "working fluid". At present, the heat exchanger is made of stainless steel or nickel alloy material. Under ideal high temperature conditions and supercritical carbon dioxide pressure, These materials will soften.
It is understood that Kenneth Sandhage's design was inspired by a "synthetic material" previously manufactured with colleagues, which is used to make solid fuel rocket nozzles that can withstand high temperatures and pressures. Currently, Kenneth Sandhage is working with Asegun Henry from MIT to design a similar synthetic material to make a harder heat exchanger.
Ceramic zirconium carbide and metal tungsten, the combination of these two materials into complex materials can produce unexpected results. Purdue researchers have produced a ceramic-metal composite sheet, based on a simulated channel designed by Georgia Tech's Devesh Ranjan and leading a research team, showing that the composite sheet can be used to customize channels to achieve heat conversion.
The Oak Ridge National Laboratory's Edgar Lara-Curzio research team performed mechanical tests on the composite, and the University of Wisconsin-Madison's Mark Anderson research team performed a corrosion test. These tests show that this new composite can be customized for supercritical carbon dioxide High temperature and high pressure conditions, thereby generating electricity more efficiently than current heat exchangers.
An analysis by researchers at Georgia Institute of Technology and Purdue University shows that compared with stainless steel or nickel alloy heat exchangers, heat exchangers made with new materials can be scaled up at the same or lower cost.
Kenneth Sandhage said that with the continuous development of technology, the technology will extend from large-scale renewable solar energy to the grid field, which means that human-made carbon dioxide emissions in power production will be significantly reduced.