Solar chimneys have the potential to meet a growing need for innovative renewable energy systems. When most people think of renewable energy, photovoltaic solar panels are often the first thing that comes to mind. However, solar chimneys are uniquely positioned to fill in the major gaps and shortcomings of solar panel technology.
Solar Chimneys vs Solar Panels
Solar chimneys and solar panels may sound like similar technologies, but they are quite different. Solar panels convert sunlight into energy. When no sunlight is shining on them, the panels cannot generate any power. However, solar panels remain an important renewable energy source. They’ve gained popularity over recent years, lowering energy costs and creating new jobs. Solar renewable energy technology can still be improved, though.
Solar chimneys don’t rely on direct sunlight. A solar chimney is a vertical tower ranging from 2 to 20 meters tall with turbines at its base. The generator inside the tower uses the kinetic energy of warm air rising up the tower to create power. All that’s needed to generate electricity with a solar chimney is warm air, which can be found both night and day in many areas.
Advantages of Solar Chimneys
Solar chimneys have a few key advantages over solar panels and other forms of renewable energy. Studies of solar chimneys point out that they can store heat and generate pure solar power around the clock. They don’t require any kind of complex water cooling system, either, making solar chimneys particularly valuable in poor or water-starved areas.
Solar chimneys have versatile potential for commercial use, as well. For example, small solar chimneys could be installed on homes, whether professionally installed in place of a traditional chimney or integrated into the roof for a zero-input ventilation system. The way that solar chimneys use thermodynamics allows them to potentially create a home ventilation system that would require no input power. The rising heat from the home would even help power the solar chimney in addition to the sun, as warm air from inside is exhausted through a vent that passes over the solar chimney.
Solar Chimney Challenges
Unfortunately, there’s a reason that solar chimneys are not dotting cities and homes all over the world yet. Solar chimneys are highly expensive to build and their low efficiency means they need to be built quite large to be a valuable return on investment. With increased research and development, this could change down the road. However, lack of funding for any early solar chimney plants is making it difficult for scientists and researchers to make progress.
For example, one solar chimney plant designed for a location in western Australia was estimated to cost $1.67 billion. One of the project’s leaders commented to National Geographic that this price alone warded off many potential investors, largely because solar chimney technology is not widely used or known. The power plant would be less expensive to build if it could be smaller, but the low efficiency of solar chimneys makes this unfeasible.
While photovoltaic solar panels convert about 8 to 15% of the energy they collect into electricity, solar chimneys can only convert about 1 to 2% into electricity. Of course, solar chimneys can operate night and day, while solar panels can only operate on sunny days. So, things balance out such that solar chimneys can actually be competitive with solar panels. On paper, though, investors and government officials may not recognize this. Greater awareness of solar chimney technology and increased development will help increase the popularity of this valuable renewable energy source.
Revolutionizing Renewables
In order for the world to meet the challenges of climate change, we need to keep an open mind to any and all renewable energy sources. Wind and solar energy are great sources of green energy, but there are many, many more, some of which we may not even have discovered yet. Solar chimneys are a lesser-known renewable energy technology, but they hold incredible potential to fill an important gap in the global renewable energy lineup.