Sunday, March 21, 2010

Concentrated Solar Power is HOT!

The Sun's free, clean, renewable energy can be used in a variety of ways to satisfy our needs for power. Solar electric power can be generated using photovoltaic cells. Solar water heaters can be used on rooftops to generate hot water for home use. But what is becoming really hot, in more ways than one, is Concentrated Solar Power (CSP), which can raise the temperature of fluids to 400 degrees Celsius, four-times higher than the boiling point of water. The super-hot fluid can be used to convert water to steam for driving turbines that generate electricity.

The CSP technique concentrates solar radiation using parabolic mirrors to obtain higher temperatures. This reduces the plant's collector size and land use, thereby reducing the environmental impacts of the power plant and its cost. The curved mirrors reflect solar radiation onto a glass tube containing a fluid running the length of the parabolic trough positioned at the focal point of the reflectors. The trough tilts east to west to track the sun so that the direct radiation remains focused on the fluid-filled tube.

But how can the CSP technique generate power at night or when it becomes cloudy during the day? A New York company in Rochester, Bell Independent Power Corp., is a developer of Thermal Storage Technology for CSP. They have chosen the University of Arizona Tech Park as the site of a new state of the art 5-MW solar plant with a Thermal Storage System, said to be the first of its kind in the world.

The role of the Arizona CSP facility is to demonstrate Bell Independent Power Corp.’s proprietary Thermal Storage System and show how its improved efficiency can reduce the cost of producing solar power. Bell's Thermal Storage System will be able to store the sun’s heat for several hours, allowing the CSP plant to generate power after sunset or when clouds move in. It will also provide sufficient energy for full plant start-up every morning, replacing the need for natural gas. If the demonstration is successful, Thermal Storage at this facility will lead to its use on large scale facilities.

The projected cost of the facility is $32 million and it will use 45 acres of parabolic mirrors to capture the solar energy. Bell Independent Power Corp. will develop, finance, own and operate the plant. Permitting has begun and, with the help of economic development incentives, the plant will begin providing power to Tucson Electric Power customers in May 2011. The plant’s construction will employ 75 workers and 7 full time positions will be established for the operation of the facility. The CSP plant and storage system is expected to produce enough energy to power more than 1,500 typical Tucson homes while offsetting more than 16,000 tons of carbon dioxide.

Read more here and visit Rochester's Bell Independent Power here.