Solar Power...at Night?
To date, conventional solar power systems have relied on drawing on the power of the Sun during the daytime to convert light energy into usable forms of energy, like electricity. This concept, of absorbing solar energy during the daytime, is indeed the standard across most modern solar power technology. But, according to a team of researchers in Qatar and Jordan, this doesn’t have to be the case. With their original concept, they managed to develop a new solar power station that not only functions both at day and night, they also more than doubled the energy output of current solar power systems.
They are calling this new project the solar tower. Although similar in name the concept behind the two sources of energy are very different. Solar panels absorb light and turn it into electricity using photovoltaic materials. They use conventional technology to create power. Solar towers, however, primarily rely on the fact that hot air rises, hence the name tower. The towers are typically made from glass or other greenhouse material that are good at trapping heat. Air is heated at surface level and rises as expected. It then spins a turbine to produce electricity.
The researchers’ proposed design (Tech Xplore)
This idea, despite its promise, is still in its infancy and remains experimental. Building the large glass towers for mainstream use remains prohibited. There are emerging designs including the twin-technology tower that could bring down cost by producing over twice as much power as previous designs, the researchers state. In this design, a secondary tower is placed around the inner tower. The secondary tower serves as a cooling tower, in which air is sent downward to spin another turbine. The researchers suggest spraying a mist of water into the hot air that is at the top of the tower will make it cooler and send it downward.
A Spanish prototype of a solar updraft tower built in the 1980s (Recharge)
This system sounds great but has clear limitations.There is an obvious concern of access to the water that will continuously supply this downward draft. Additionally, although the effectiveness of the proposed model could lower the potential cost, there are still major doubts about the feasibility of widespread use of this model. However, solar panels were also doubted in their early stages of existence, and their presence in today’s world as the dominant force in renewable energy is an example of why ideas such as the solar tower should not be dismissed. As more time passes on, it is more likely that emerging ideas will continue to revolutionize the industry we rely upon.
