We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

What is a Solar Furnace?

Michael Anissimov
Updated: May 23, 2024

A solar furnace is any device that creates heat by concentrating solar radiation through the use of reflectors. A small one may be used to cook food without consuming firewood, whereas a larger one can generate electricity by heating a gas. There have been attempts to introduce the technology to developing countries to minimize firewood-related deforestation, but only with limited success.

The principle of operation of a solar furnace is quite simple. Take two mirrors, point them at a focus, and the intensity of sunlight in that focus will increase by around threefold. This is because, instead of only getting light from the sun, the focus gets light from the sun and two mirrors. Make that ten mirrors, and you start to get levels of heat that are useful for applications like cooking food.

At least a few groups of hobbyists have made a solar furnace that generates over a thousand degrees of heat, capable of reducing most organic material to ash. In principle, the main limitation of how much solar energy can be focused on one spot is a function of how accurately the mirrors can be aimed at the focus. The solar furnace is one of those technologies that our ancestors would have found extremely useful, if only they had the means to manufacture highly reflective mirrors, which they didn’t. Ancient mirrors were merely polished silver or copper, whereas modern mirrors consist of a thin layer of aluminum deposited on glass.

A dish-Stirling system is a solar furnace that uses parabolic mirrors to focus sunlight on rock salt, which melts and can be used to heat water and produce steam to drive a turbine. These are more efficient than photovoltaic solar cells. It is said that the Greek inventor Archimedes used a solar furnace to set enemy ships on fire during a war, but this is unlikely, as he didn’t possess the technology to focus mirrors that precisely on a target more than a few feet away.

The Solar Panel Guide is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Michael Anissimov
By Michael Anissimov
Michael Anissimov is a dedicated The Solar Panel Guide contributor and brings his expertise in paleontology, physics, biology, astronomy, chemistry, and futurism to his articles. An avid blogger, Michael is deeply passionate about stem cell research, regenerative medicine, and life extension therapies. His professional experience includes work with the Methuselah Foundation, Singularity Institute for Artificial Intelligence, and Lifeboat Foundation, further showcasing his commitment to scientific advancement.
Discussion Comments
By anon98079 — On Jul 22, 2010

does a solar furnace generate as much heat as two ranges?

By anon18144 — On Sep 16, 2008

which gas is used for heating and generating electricity???

Michael Anissimov
Michael Anissimov
Michael Anissimov is a dedicated The Solar Panel Guide contributor and brings his expertise in paleontology, physics,...
Learn more
The Solar Panel Guide, in your inbox

Our latest articles, guides, and more, delivered daily.

The Solar Panel Guide, in your inbox

Our latest articles, guides, and more, delivered daily.