A Solar Power tower is a tower used to receive concentrated solar power. It is usually surrounded by heliostats or flat movable mirrors that capture the sun’s rays and reflect it to the Solar Tower in the middle. Below you can watch a video of the tallest Solar tower being constructed in an Israeli Desert. This tower is encircled by 50,000 heliostats and should reach a height of 250 meters once completed.
Source: Telegraph
However, whether these power towers will ever become successful? We at Greenworldinvestor had sounded the end of the solar thermal technology years ago, saying that the technology was no longer competitive with silicon solar PV technology. Today the prices of mainstream silicon has fallen and is already competitive to the prices of traditional sources of power. Many of these towers are being replaced with solar PV technology.
The Ivanpah Solar Power plant which was constructed in California by Brightsource Energy costed $2.2 billion is already running into trouble. The power tower has failed to generate the required power as per the contract with Californian utilities. These power towers are still a niche technology and on top of it is the falling solar PV costs, which makes this technology look even worse.
Here are some of the Disadvantages of Solar Thermal Energy
2) Future Technology has a high probability of making CSP Obsolete – Solar energy has become a hotbed of innovation with daily news of some new breakthrough in materials and process in PV Technology. This has made PV solar the popular choice amongst masses.
3) Water Issue – Solar Thermal Plants use lots of water which is major problem in desert areas. Using non-water cooling raises the cost of CSP projects too much. While using sea water has been proposed it remains to be seen if it possible to implement this solution.
4) Ecological and Cultural Issues – The usage of massive arrays of mirrors is noted to heavily impact the desert wildlife harming the endangered species. The mirrors create an effect of water bodies, which naturally attract birds and animals who eventually die because of high temperatures in the vicinity.
5) Limited Locations and Size Limitations – Solar Thermal Energy can only be built in places which have the high amount of solar radiation. They can be built in deserts mostly and require a large land area. This means its not possible to build them in populated areas. Solar Thermal Energy also can only be built in large sizes which are at least 50 MW in size to be economical. This contrasts to Solar PV which is sold in sizes as low as 5 Watts.
6) Long Gestation Time Leading to Cost Overruns – The gestation time for permitting, financing, drilling etc. can easily take 5-7 years to develop a concentrated solar thermal power plant. Compare this to 6 months for a small wind farm or 3 months for a Solar PV plant.
7) Financing – is the biggest problem in developing projects particularly for small solar thermal developers in this industry.
The Solar Power towers are still in a conceptual stage and we shall wait for the technology to find its foot hold in niche areas of power generation.