Solar power tower is a technology that has been developed for many years but has not made much commercial progress. Just like solar panels, this technology could only work during the day, but it requires very suitable conditions and large scales to be an economical energy source. These factors are the main reasons why this system cannot be a commercial form of energy.
A joint study conducted between researchers in Jordan and Qatar focused on exactly these problems and identified design deficiencies and problems in solar energy towers. The standard installation of solar towers uses large, circular glass collectors to heat the air above them using sunlight. Afterwards, the heated hot air rises, this heated air is passed through a long updraft tower and moves a turbine in the tower.
New solar tower design
In their analysis, the researchers found that this type of traditional solar tower design had a lower thermal efficiency. To improve the output of the system, larger glass collectors need to be used, which further increases the input cost of the installation and pushes the concept away from commercialization.
Adding water makes the air heavier and colder, which pulls the molecules downward as a result of gravity. This downstream flow is then directed into narrow channels with turbines placed externally on the chimney tower, producing more electricity.
Energy output and limitations
Although TTSS has higher applicability than previous conventional systems, researchers acknowledge that the performance of the device is greatly affected by high humidity and is therefore ideal for hot, dry weather. A simulation test using local weather data from Riyadh, the capital of Saudi Arabia, shows that a single TTSS can produce 753 MWh of energy annually, with 350 MWh of energy produced by the updraft tower and the downdraft tower producing 400 MWh of energy.
Additionally, when used in hot desert conditions, the need for constant water in the system also emerges as a limitation. Researchers are now working on how this solution can be scaled and integrated with other types of renewable energy.