Posting in Design
Scientists at the U.S. Department of Energy's Idaho National Laboratory in Idaho Falls have fused nanotechnology to solar cells in order to harvest infrared radiation - day or night.
Scientists at the U.S. Department of Energy's Idaho National Laboratory in Idaho Falls are harnessing infrared radiation to produce a solar cell that will work even in the dark of night, UPI reports.
The energy of electromagnetic radiation surrounds us, but is only light is visible to the human eye. The full electromagnetic spectrum includes radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays and gamma rays.
Yet, most existing solar panels have only effectively harnessed light energy while allowing nearly half of the energy in the spectrum (in the form of infrared waves) to pass by mostly unused. It took the nation's top nuclear laboratory to fully comprehend the potential of radiation.
Idaho National Laboratory scientist Steven Novack first announced its intention to utilize both infrared radiation and visible light in 2008. The capture of infrared radiation is made possible by specially designed nano-antennae that are grafted onto the surface of photovoltaic solar panels.
Novack announced the completion of an infrared ready solar cell today. The system, which can absorb radiation at many angles, has an estimated overall efficiency of 46 percent, he told UPI. Conventional solar cells are 25 percent efficient under optimal light conditions.
Other approaches to overcome darkness have combined solar power with thermal power technologies. SolarReserve has developed a system that uses solar energy to heat molten salts during the daytime, which in turn generate heat that spin turbines at night.
Dec 20, 2010
In order to have a more reliable source of renewableenergy. The system has to be a combination of PV, Wind and Geothermal. Prior to installing a renewable energy system, an energy efficiency implementation is imperative. Yj Draiman, Energy/Utility auditor
these researchers aren't even close to catching up with technology which Nikola Tesla was playing with 120 years ago. He had tuned coils which could harness the earths magnetic fields to produce electricity - which of course would obviously work day and night ... so solar is "technically" old hat
The amount of downward long wave radiation is miniscule at night and varies greatly with such atmospheric events as daytime temperature, humidity and cloud cover. Simply put, this is why clear winter nights are usually colder than cloudy winter nights. Long wave radiation from the earth escapes into space on a clear night, but is reflected back to earth on cloudy nights. The efficiency of this equipment would vary greatly with those conditions making it unreliable for power at night.
Solar energy at night Some solar power plants in Spain were selling solar energy at night. I think they will finish their investigations in jail.
Infrared radiation comes from all angles, not just the surface. Try looking up "downward longwave radiation".
Once again naive and inexperienced Smart Planet reporters have goofed. Anybody who has even a basic training in science would know that nightime infra red isn't powerful enough to bother about. And (hilariously) nightime infra red radiation comes from the ground so the panels would have to flip over at nightfall and face downwards!!!! What a laugh.
Most existing solar cells already harvest energy from the infrared part of the spectrum. Just look at the spec sheet in any solar cell manufacturers' catalog. What these DOE scientists appear to have done is improve the collection in this part of the spectrum. I suspect it is the reporter who misunderstood this.
Sounds to me like these are solar panels which harvest energy from more of the solar spectrum, not ones which work in darkness. Still though; 46% efficient solar panels - way to go!
Unless I miss my guess here, this article has an incredibly large hole in its coverage. Sun light radiates at 1000 Watt/m2 which is pretty intense. Background radiation is orders of magnitude lower in intensity making this an unusable source of energy. However, this may have applications such as heat recovery from catalytic converters on cars.