photoelectric effect

[fifaman]

Hi all

Im fifaman and im new 'ere

 

just wanna ask if it's possible to harvest the full range of the em spectrum for electricity

 

and if so, I'm wondering if the gamma radiation put out by a nuclear reactor contains alot of energy as a whole since gamma photons are high energy

 

also would like to ask how it is to be done or for some ideas on what to do

 

thanks alot

cheers

[npts2020]

Hi all

Im fifaman and im new 'ere

 

just wanna ask if it's possible to harvest the full range of the em spectrum for electricity

 

and if so, I'm wondering if the gamma radiation put out by a nuclear reactor contains alot of energy as a whole since gamma photons are high energy

 

also would like to ask how it is to be done or for some ideas on what to do

 

thanks alot

cheers

 

AFAIK it is possible to use the full EM spectrum to produce electricity but there are ranges, particularly on the low end of the spectrum, where it is probably not practical to do so. Not all gamma radiation is high energy. For instance, visible light is not generally considered to be high energy.

The reactors currently in widespread use do not primarily use gamma radiation, even though there is a lot of it, for heating water (which is where the energy is extracted from to make electricity), it is neutron radiation. The thermal reactors used for electrical generation work by heating water to make steam, which is put through a turbine, which turns a generator to make the electricity.

[swansont]

The reactors currently in widespread use do not primarily use gamma radiation, even though there is a lot of it, for heating water (which is where the energy is extracted from to make electricity), it is neutron radiation. The thermal reactors used for electrical generation work by heating water to make steam, which is put through a turbine, which turns a generator to make the electricity.

 

The majority of the energy released in fission is in the kinetic energy of the fission fragments. Much of the energy of the neutrons and gammas are also deposited in the reactor, contributing a small amount to the thermal power.

 

You could try and use the photoelectric effect to collect the energy of escaping gammas, but it would be impractical. Gammas tend to penetrate, and would very likely pass through the device rather than interact.

[vuquta]

The majority of the energy released in fission is in the kinetic energy of the fission fragments. Much of the energy of the neutrons and gammas are also deposited in the reactor, contributing a small amount to the thermal power.

 

You could try and use the photoelectric effect to collect the energy of escaping gammas, but it would be impractical. Gammas tend to penetrate, and would very likely pass through the device rather than interact.

 

Correction, Compton scattering

In physics, Compton scattering is a type of scattering that X-rays and gamma rays undergo in matter. The inelastic scattering off electrons in matter results in a decrease in energy (increase in wavelength) of an X-ray or gamma ray photon, called the Compton effect. Part of the energy of the X/gamma ray is transferred to a scattering electron, which recoils and is ejected from its atom, and the rest of the energy is taken by the scattered, "degraded" photon.

http://en.wikipedia.org/wiki/Compton_scattering

[fifaman]

so compton scattering occurs while the gamma ray ionises stuff?

[swansont]

so compton scattering occurs while the gamma ray ionises stuff?

 

It happens when the energy of the gamma is much higher than the ionization energy, so the electron no longer "looks" like a bound electron. A free electron cannot absorb a photon.

[npts2020]

The majority of the energy released in fission is in the kinetic energy of the fission fragments. Much of the energy of the neutrons and gammas are also deposited in the reactor, contributing a small amount to the thermal power.

 

You could try and use the photoelectric effect to collect the energy of escaping gammas, but it would be impractical. Gammas tend to penetrate, and would very likely pass through the device rather than interact.

 

Thanks for the correction. I was not considering the alphas and betas produced since they don't make it outside of the core into the water coolant. They do produce considerably more heat overall.