Solar Thermal Energy

Solar thermal energy has been losing out in the last couple of years to solar photovoltaic energy which is seeing a huge increase in demand amidst very low prices. Some of the major solar thermal energy projects in the globe have been converted into solar PV installations due to its lower costs. Some of the major solar thermal energy companies like Solar Millennium have sold their solar thermal portfolios to other companies while Stirling Power Systems has gone bankrupt. Tessera has sold its solar thermal plants which had gotten DOE Loan Guarantees in California to Solar Developers who have made these solar thermal plants into solar panel ones. However there are some companies like eSolar and Brightsource Energy which are powering ahead with their technologies and projects with backing from big industrial MNC  conglomerates like GE and Areva. Their Power Tower Technologies are supposedly more efficient than the mainstream parabolic toughs that are used.

Advantages of Solar Thermal Energy

1) No Fuel Cost – Solar Thermal Energy does not require any fuel like most other sources of renewable energy. This is a huge advantage over other fossil fuels whose costs are increasing at a drastic  rate every year. Electricity prices are increasingly rapidly in most parts of  the world much faster than general inflation. Price shocks due to high fuel costs are a big risk with fossil fuel energy these days.

2) Predictable, 24/7 Power -Solar Thermal Energy can generate power 24 hours a day. This is made possible as solar thermal power plants store the energy in the form of molten salts etc. Other forms of Renewable Energy like Solar PV and Wind Energy are intermittent in nature. The electricity supply is much more uniform and reliable.

3) No Pollution and Global Warming Effects – Solar Thermal Energy does not cause pollution which is one of the biggest advantages. Note there are costs associated with the equipment used to build and transport Solar Thermal Energy Equipment.

4) Using Existing Industrial Base – Solar Thermal Energy uses equipment like solar thermal mirrors and turbines which is made in large scale at low cost by the existing Industrial Base and requires no major changes in equipment and materials unlike new technologies such as CIGs Panels.

Disadvantages of Solar Thermal Energy

1) High Costs – Solar Thermal Energy costs at least Euro 3.5/watt and has not declined too much in the last 3-4 years. However these costs are too high  as Solar PV already costs Euro 2.5/watt and even on a conservative basis will have its costs reduced by 5% in the next 10 years making it attain half the cost of Solar Thermal Technology by 2020.

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. Oerlikon has come out with a radial new a-Si Technology while CIGs player are touting increased efficiencies. Chinese Solar Companies have captured large chunks of the Solar Market through low cost leadership while number of Global Heavyweights like Posco, Samsung, Hyundai, Sharp, GE, TSMC promise to further decrease these costs.

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 as this would imply building Plants very near the Coastline.

4) Ecological and Cultural Issues – The Usage of Massive Arrays of Mirrors is noted to heavily impact the Desert  Wildlife endangering the endangered species. California has already seen a massive fight on this issue with Project Developers curtailing the size of their Plants and spending money to move the wildlife.

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.

Read about the Advantages and Disadvantages of Natural Gas, Nuclear Energy and Coal