In the prototype, sunlight heats a ceria cylinder which breaks down water or carbon dioxide

The machine uses the Sun’s rays and a metal oxide called ceria to break down carbon dioxide or water into fuels which can be stored and transported.

Conventional photovoltaic panels must use the electricity they generate in situ, and cannot deliver power at night.

The prototype, which was devised by researchers in the US and Switzerland, uses a quartz window and cavity to concentrate sunlight into a cylinder lined with cerium oxide, also known as ceria.

Ceria has a natural propensity to exhale oxygen as it heats up and inhale it as it cools down.

If as in the prototype, carbon dioxide and/or water are pumped into the vessel, the ceria will rapidly strip the oxygen from them as it cools, creating hydrogen and/or carbon monoxide.

Hydrogen produced could be used to fuel hydrogen fuel cells in cars, for example, while a combination of hydrogen and carbon monoxide can be used to create “syngas” for fuel.

It is this harnessing of ceria’s properties in the solar reactor which represents the major breakthrough, say the inventors of the device. They also say the metal is readily available, being the most abundant of the “rare-earth” metals.

Methane can be produced using the same machine, they say. Refinements needed  The prototype is grossly inefficient, the fuel created harnessing only between 0.7% and 0.8% of the solar energy taken into the vessel. Most of the energy is lost through heat loss through the reactor’s wall or through the re-radiation of sunlight back through the device’s aperture. But the researchers are confident that efficiency rates of up to 19% can be achieved through better insulation and smaller apertures. Such efficiency rates, they say, could make for a viable commercial device. “The chemistry of the material is really well suited to this process,” says Professor Sossina Haile of the California Institute of Technology (Caltech). “This is the first demonstration of doing the full shebang, running it under (light) photons in a reactor.”

She says the reactor could be used to create transportation fuels or be adopted in large-scale energy plants, where solar-sourced power could be available throughout the day and night. However, she admits the fate of this and other devices in development is tied to whether states adopt a low-carbon policy. “It’s very much tied to policy. If we had a carbon policy, something like this would move forward a lot more quickly,” she told the BBC. It has been suggested that the device mimics plants, which also use carbon dioxide, water and sunlight to create energy as part of the process of photosynthesis. But Professor Haile thinks the analogy is over-simplistic.

“Yes, the reactor takes in sunlight, we take in carbon dioxide and water and we produce a chemical compound, so in the most generic sense there are these similarities, but I think that’s pretty much where the analogy ends.”

The PS10 solar tower plant near Seville, Spain. Mirrors concentrate the sun’s power on to a central tower, driving a steam turbine

Daniel Davies, chief technology officer at the British photovoltaic company Solar Century, said the research was “very exciting”.

“I guess the question is where you locate it – would you put your solar collector on a roof or would it be better off as a big industrial concern in the Sahara and then shipping the liquid fuel?” he said.

Solar technology is moving forward apace but the overriding challenges remain ones of efficiency, economy and storage.

New-generation “solar tower” plants have been built in Spain and the United States which use an array of mirrors to concentrate sunlight onto tower-mounted receivers which drive steam turbines.

A new Spanish project will use molten salts to store heat from the Sun for up to 15 hours, so that the plant could potentially operate through the night.

WASHINGTON — Astronomers using NASA’s Chandra X-ray Observatory have found evidence of the youngest black hole known to exist in our cosmic neighborhood. The 30-year-old black hole provides a unique opportunity to watch this type of object develop from infancy.

The black hole could help scientists better understand how massive stars explode, which ones leave behind black holes or neutron stars, and the number of black holes in our galaxy and others.

The 30-year-old object is a remnant of SN 1979C, a supernova in the galaxy M100 approximately 50 million light years from Earth. Data from Chandra, NASA’s Swift satellite, the European Space Agency’s XMM-Newton and the German ROSAT observatory revealed a bright source of X-rays that has remained steady during observation from 1995 to 2007. This suggests the object is a black hole being fed either by material falling into it from the supernova or a binary companion.

“If our interpretation is correct, this is the nearest example where the birth of a black hole has been observed,” said Daniel Patnaude of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. who led the study.

The scientists think SN 1979C, first discovered by an amateur astronomer in 1979, formed when a star about 20 times more massive than the sun collapsed. Many new black holes in the distant universe previously have been detected in the form of gamma-ray bursts (GRBs).

However, SN 1979C is different because it is much closer and belongs to a class of supernovas unlikely to be associated with a GRB. Theory predicts most black holes in the universe should form when the core of a star collapses and a GRB is not produced.

“This may be the first time the common way of making a black hole has been observed,” said co-author Abraham Loeb, also of the Harvard-Smithsonian Center for Astrophysics. “However, it is very difficult to detect this type of black hole birth because decades of X-ray observations are needed to make the case.”

The idea of a black hole with an observed age of only about 30 years is consistent with recent theoretical work. In 2005, a theory was presented that the bright optical light of this supernova was powered by a jet from a black hole that was unable to penetrate the hydrogen envelope of the star to form a GRB. The results seen in the observations of SN 1979C fit this theory very well.

Although the evidence points to a newly formed black hole in SN 1979C, another intriguing possibility is that a young, rapidly spinning neutron star with a powerful wind of high energy particles could be responsible for the X-ray emission. This would make the object in SN 1979C the youngest and brightest example of such a “pulsar wind nebula” and the youngest known neutron star. The Crab pulsar, the best-known example of a bright pulsar wind nebula, is about 950 years old.

“It’s very rewarding to see how the commitment of some of the most advanced telescopes in space, like Chandra, can help complete the story,” said Jon Morse, head of the Astrophysics Division at NASA’s Science Mission Directorate.

The results will appear in the New Astronomy journal in a paper by Patnaude, Loeb, and Christine Jones of the Harvard-Smithsonian Center for Astrophysics. NASA’s Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for the agency’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra’s science and flight operations from Cambridge.

For more information about Chandra, including images and other multimedia, visit:

http://chandra.nasa.gov

and

http://chandra.harvard.edu