The team of collaborators of Nizhyn laboratories of scanning devices (Ukraine) develops the new molecular and quantum-electronic electrical power technologies and equipment based on the use of active gas mixtures as a working body in the solar power systems and permits to overcome the lacks of existent power heliotechnologies.

One of them, named Controlled electrical gas discharge under multiphotonic laser ionization radiation, is based on the method of multiphotonic ionization in gases under laser radiation that occurs in an electromagnetic resonator under action of the concentrated sun radiation. Multiphotonic ionization forms the guided electric gas discharge in the closed gas environment. A frequency of laser radiation is usually insufficient to ensure the ionization by absorption of one photon. But extraordinarily high density of stream of photons in a laser beam gives a possibility ensuring ionization conditions by simultaneous absorption of a few photons by means of multiphotonic ionization.

An idea of using of active gas mixtures as a working body is not new. The gas mixtures were widely used in molecular lasers, which make use of electronic, vibrational or rotational energy levels in molecules. The molecules can be excited by an electric discharge, as in the case of the N₂ or CO₂ laser, by chemical reactions, as in the HF or DF lasers, or by another laser, as in the CH3F far IR laser.

 A pilot plant includes a cavity (discharge tube) filled by gas mixture. The filling gas within the discharge tube consists of carbon dioxide CO₂ (10…20 %); nitrogen N₂ (10…20%); hydrogen H₂ and/or Xe (a few percent); helium He (the remainder of the gas mixture). This mixture corresponds to that of Carbon dioxide laser, which is the highest power continuous wave laser that is currently available. The active laser medium is a gas discharge which is water cooled in higher power applications. The CO₂ laser can be constructed to have powers between milliwatts and gigawatts. It is also very easy to actively Q-switch a CO₂ laser, giving rise to Q-switched peak powers 100 to 1000 times higher than the equivalent continuous wave laser of any particular design.

The population inversion in the laser cavity filled by carbon dioxide gas mixture is achieved by the following sequence. Primarily multiphotonic ionization frees a few initiating electrons. They are accelerated by the electromagnetic field of light wave, shock and in addition to the light excite (ionize) the molecules and atoms. Electron impact excites vibrational motion of the nitrogen. Because nitrogen is a homonuclear molecule, it cannot lose this energy by photon emission, and its excited vibrational levels are therefore metastable and live for a long time. Collisional energy transfer between the nitrogen and the carbon dioxide molecule causes vibrational excitation of the carbon dioxide, with sufficient efficiency to lead to the desired population inversion necessary for laser operation.

On the base of this technology the Coherent Solar Gas Discharge Electrical Power Station are created.

The chart of coherent gas discharge solar power station includes a gas discharge electrogenerator, optical resonator, system of concentration (pumping) of sun radiation and a system of electronic control of electric current parameters. 

Closed gas discharge electrogenerator is set into an optical resonator. An optical resonator consists of two Fresnel plates OZP1 and OZP2, set in parallel to each other; optically active body (Optical active body) and a system of optical pumping of an active body by the concentrated sun radiation (Solar radiation pumping). A gas mixture is posed into an optically transparent cylinder cavity of gas discharge electrogenerator. A destination of this cavity - to insulate a gas mixture from contact with an atmosphere and provide the flow of ionization processes in closed spacious.

The block of concentration of radiation into a long concentrator consists of row of elementary concentrators of sun energy CS1, CS2, CS3 ..., CSN, placed along the optical resonator, limited by zone plates OZP 1, OZP 2. It includes also an integral sun concentrator ConSolar. Points of focuses of elementary concentrators F1, F2, F3 ..., FN lie on the axis of optical resonator. The elementary concentrators focus the falling beam on the axial line of gas discharge electrogenerator, thus ionizing a photoactive gas mixture in a resonator and forming the line of plasma. The process of ionization is accompanied by formation of anions, cations, lone electrons and quanta of radiation.

In the process of ionization of active body (gas mixture) quanta appear. Parameters of quanta are defined by parameters of an active body and a resonator. These quanta move chaotically in a resonator. The greater part of quanta goes at once out the volume of resonator. Some of them move parallel to optical axis of resonator and excite molecules and atoms and free new portions (quanta) of radiation. In a closed electromagnetic resonator a process of origin of coherent optical radiation with a Sun radiation pumping appears. A resonator strengthens a coherent radiation. After frequent reflection of radiation by mirrors a standing wave is set in a resonator that provides transference of energy, excitation and strengthening of laser generation. The laser generation, in the turn, initiates multiphotonic ionization and an appearance of quantum-electronic avalanche that enhances more an electric discharge in a gas mixture. For the selection of the charged particles the structure of electrodes is formed within a resonator.

Passive or active optical modulator, located in a resonator, provides control of lasing parameters of resonator. The generation arises up only in the case when population density of radiate levels will exceed the switching threshold of optical modulator.

The scientists consider the power efficiency of this technology is in the limits of 30…40 %. In future it may grow to 40…60 %.

 Posted by Vasil Sidorov on March 07, 2009   in queltanews.com