Energy

Cheaper hybrid concentrated solar power plant design put to the test

Cheaper hybrid concentrated so...
MHPS is testing out a hybrid concentrated solar power system that combines a a solar power tower with a low-temperature, low-cost Fresnel evaporator
MHPS is testing out a hybrid concentrated solar power system that combines a a solar power tower with a low-temperature, low-cost Fresnel evaporator
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MHPS is testing out a hybrid concentrated solar power system that combines a a solar power tower with a low-temperature, low-cost Fresnel evaporator
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MHPS is testing out a hybrid concentrated solar power system that combines a a solar power tower with a low-temperature, low-cost Fresnel evaporator
The hybrd CSP design includes a low-temperature Fresnel evaporator (right) that produces steam that is directed to a solar tower (top left) where it is further heated by an array of heliostats (left)
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The hybrd CSP design includes a low-temperature Fresnel evaporator (right) that produces steam that is directed to a solar tower (top left) where it is further heated by an array of heliostats (left)

Concentrating solar power (CSP) plants focus the sun's thermal energy to produce steam that drives a turbine to generate electricity. Now, Mitsubishi Hitachi Power Systems (MHPS) is testing the performance of a new hybrid system that is designed to increase efficiency and lower costs by combining a solar power tower with a low-temperature Fresnel evaporator.

Conventional CSP systems are made up of arrays of heliostats, mirrors that track the sun to ensure the reflected light is always pointed at a specific target. While they're more complex and costly than photovoltaic setups, CSP systems can better deal with fluctuations in the strength of the sunlight, and their energy production is more stable at night or in cloudy conditions as the thermal energy can be stored and used to continue producing power long after the sun has set.

Laid out over 10,000 sq m (107,639 sq ft), MHPS's test facility is made up of 150 heliostats, a superheater built into a tower, and a low-cost Fresnel evaporator. Of the overall sunlight collected at the plant, the evaporator pulls in 70 percent, thanks to a plane of mirror surfaces with adjustable angles. Using the resulting thermal energy, the Fresnel evaporator heats water to produce steam at temperatures of around 300° C (572° F).

The hybrd CSP design includes a low-temperature Fresnel evaporator (right) that produces steam that is directed to a solar tower (top left) where it is further heated by an array of heliostats (left)
The hybrd CSP design includes a low-temperature Fresnel evaporator (right) that produces steam that is directed to a solar tower (top left) where it is further heated by an array of heliostats (left)

That steam is then channeled into the superheater located at the top of a small tower, where it is further heated to 550° C (1,022° F) via sunlight focused by the heliostats. Since the steam is already pre-heated, a smaller array of heliostats is required to superheat the steam, so it can do so at a lower cost than previous CSP systems. MHPS says its hybrid test system is capable of generating the equivalent of 300 kW of electricity.

Working at its Yokohama Works facility under contract from Japan's Ministry of the Environment, MHPS will run tests until March 2017 to verify if its hybrid sunlight collection system can improve on the efficiency of existing CSP technologies. Testing of a high-temperature thermal energy storage system will also begin in October to test whether the system can stably supply power without the help of fossil fuel-based systems.

Source: Mitsubishi Hitachi Power Systems

4 comments
DavidBrewer
Happy to see any advances in any fossil fuel alternative, but even this will be too little too late. Would be nice to see here articles on, and promote a technology that could really delivery on all the unrealized promises of solar. Specifically LFTR (Liquid Fluoride Thorium Reactor) or any of the competing low pressure thorium reactor design alternatives being proposed. Modular, massively efficient, non-proliferating, virtually inexhaustible, energy production technology that could also clean up decades of old reactor waste. It appears the Chinese will beat the US to commercializing this and then we can pay them for the IP (or just burn through our existing fossil fuels and leave the mess to future generations to clean). We created the technology at ORNL in 1955 and left it to gather dust, since it couldn't produce weapons grade fuels at the time our nuclear energy program emerged. Can you try to provide some coverage?
S Michael
It will be countries like Japan, China, India and other countries that are not controlled or influenced by big oil, big energy, big grid. Once these countries develop these energy producing plants, the technology will get out, and the U.S. people will point to them and force the construction of such plants. Keep an eye on India. They are the leaders in personal power plants that will give every American and others true independence.
tsvieps
To S Michael, I am tired of unjustified slander against anyone. What is your evidence that oil companies or utility companies are preventing the development of Thorium Reactors? New fission reactors that burn fuel remnants from the current generation of nuclear reactors are in fact under development. Bill Gates has a sizeable investment in one company developing such reactors.
WilliamSager
One cost saving method for countries with existing energy grids is to piggyback solar facilities like this with current coal or oil fired powered power plants.During the day the facility can use the sun to heat the water to power the existing steam turbines.At night or cloudy days fossil fuels could be used to power the turbines.This takes advantage of current steam turbines and electric grids already in place.