A technology inspired by the Bronze Age could help us reach the United Nations’ goal of net-zero emissions by 2050, according to recent research led by Stanford University and published in PNAS Nexus.
This innovative approach involves using heat-absorbing bricks, similar to those used thousands of years ago, to store heat generated by solar or wind power.
These bricks are placed in an insulated container and can store heat for later use, making it possible for factories to run on renewable energy even when the sun isn’t shining or the wind isn’t blowing.
These systems are called thermal energy storage, and several companies are already commercializing them.
The bricks, known as “firebricks,” are made from materials similar to those used in ancient kilns and furnaces but are optimized for heat storage.
One major advantage of firebrick storage over battery storage is cost. According to lead study author Mark Z. Jacobson, a professor at Stanford, firebricks are one-tenth the cost of batteries. “The materials are much simpler too. They are basically just the components of dirt,” Jacobson said.
High heat storage for industry
Many industries need extremely high temperatures to manufacture products.
For instance, cement production requires temperatures of at least 1,300 degrees Celsius (nearly 2,400 degrees Fahrenheit), and glass, iron, and steelmaking need temperatures of 1,000 C (about 1,800 F) or higher.
Currently, about 17% of global carbon dioxide emissions come from burning fossil fuels to produce this industrial heat.
Storing energy as heat, rather than converting it back and forth between electricity and heat, reduces inefficiencies. “If you need heat for industry, store it in firebricks,” said Daniel Sambor, a co-author of the study.
The researchers examined the impact of using firebricks to store industrial heat in 149 countries, responsible for nearly all global carbon dioxide emissions from fossil fuels.
They used computer models to compare scenarios with and without firebricks in a future where these countries rely entirely on renewable energy.
In the scenario with firebricks, they found that using these bricks could cut capital costs by $1.27 trillion across the 149 countries compared to relying solely on electric furnaces and batteries for industrial heat. Firebricks also reduce the demand for electricity from the grid and the need for expensive battery storage.
Transitioning to clean energy also has significant health benefits. Burning fossil fuels causes air pollution, leading to millions of early deaths each year. “Every bit of combustion fuels we replace with electricity reduces that air pollution,” Jacobson said.
Jacobson’s career has focused on understanding air pollution and climate problems and developing energy plans to address them. His interest in firebricks is relatively new but driven by the potential for rapid adoption and significant impact.
“If we propose an expensive and difficult method of transitioning to renewable electricity, we’d have very few takers. But if this will save money compared to previous methods, it will be implemented more rapidly,” Jacobson explained.
“The impact is very large, with benefits from reducing air pollution to making it easier to transition to clean renewables.”
In summary, using ancient-inspired firebricks for heat storage could play a crucial role in achieving a cleaner, more sustainable future.
