Soon, solar panels will produce electricity in cloudy weather and at night

Scientists have developed a material that can be used to harvest electricity from the heat of the sun, paving the way for cheaper solar power generation on cloudy days and at night. .

Innovation is an important step to use solar heat. According to the researchers, the production of electricity in direct competition with fossil fuels is related to the cost.

"Storing solar energy in the form of heat can already cost less than storing energy via batteries, the next step is to reduce the cost of electricity production from the heat of the Sun. Kenneth Sandhage, professor at Purdue University in the United States

Concentrating solar power plants convert solar energy into electricity by using mirrors or lenses to focus a lot of light on a small area, which generates heat that is transferred to a molten salt.

The heat of the molten salt is then transferred to a "working" fluid, the supercritical carbon dioxide, which expands and runs to spin a turbine to produce heat.

To make solar electricity cheaper, the turbomachine would have to produce even more electricity for the same amount of heat, which meant e the engine has to run hotter.

The problem is that heat exchangers, which transfer the heat from the hot molten salt to the working fluid, are currently made from stainless steel or nickel-based alloys that are too soft at the desired higher temperatures and high pressure. of supercritical carbon dioxide. [19659002] Researchers designed a composite of ceramic zirconium carbide and metallic tungsten for more robust heat exchangers.

They created ceramic-metal composite plates. The plates contain customizable channels to adapt the heat exchange.

Mechanical tests and corrosion tests have shown that the composite material can be adapted to successfully withstand the supercritical carbon dioxide at high temperature and high pressure required to produce electricity more efficiently [19659002] An economic badysis also showed that larger-scale manufacture of these heat exchangers could be achieved at a cost comparable to or lower than that of stainless-steel or nickel-alloy heat exchangers.

The technology would allow large-scale penetration of renewable solar energy into the electricity grid, "said Sandhage.

" This would result in a significant reduction in anthropogenic carbon dioxide emissions. resulting from the production of electricity, "he said.