Related papers: R{\'e}flexions sur la puissance motrice du Soleil
It is shown that the hypothesis of the axion mechanism of Sun luminosity suggesting that the solar axion particles are born in the core of the Sun and may be efficiently converted back into $\gamma$-quanta in the magnetic field of the solar…
Heat engines cannot generally operate at maximum power and efficiency, imposing a trade-off between the two. Here, we highlight the exact nature of this trade-off for engines that exchange heat radiatively with a hot source. We derive…
A transition to a fully global renewable energy infrastructure is potentially possible in no more than a few decades, even using current wind/solar technologies. We demonstrate that at its completion this transition would terminate…
Thermophotovoltaic devices are energy-conversion systems generating an electric current from the thermal photons radiated by a hot body. In far field, the efficiency of these systems is limited by the thermodynamic Schockley-Queisser limit…
Water has been identified as a critical resource both to sustain human-life but also for use in propulsion, attitude-control, power, thermal and radiation pro-tection systems. Water may be obtained off-world through In-Situ Resource…
The energy balance for an atmospheric layer near the soil is evaluated. By integrating it over the whole day period a linear relationship between the global daily solar radiation incident on a horizontal surface and the product of the…
In this short note, we discuss a mechanism for the transport of energy, momentum and dipole moment via transient neutral carriers in plasma. This gives a way to rapidly convert bulk hydrodynamic flow energy into thermal energy over a…
The transport of energy in heated plasmas requires the knowledge of the radiation coefficients. These coefficients consist of contribution of bremsstrahlung, photoionisation, bound-bound transmissions and scattering. Scattering of photons…
A thermophotovoltaic (TPV) energy converter harnesses thermal photons emitted by a hot body and converts them to electricity. When the radiative heat exchange between the emitter and PV cell is spectrally monochromatic, the TPV system can…
Fresh water scarcity is one of the critical challenges for global sustainable development. Several novel water resources such as passive seawater solar desalination and atmospheric water harvesting have made some progress in recent years.…
One of the basic questions of solar research is the nature of the Sun. We show here how the plasma nature of the Sun leads to the self-generation of solar activity. The release of magnetic, rotational, gravitational, nuclear energies and…
Thermal conduction has been suggested as a possible mechanism by which sufficient extra heating is provided in radiation-dominated accretion flows. We consider the extreme case in which the generated energy due to the viscosity and the…
A physically consistent model of magnetic field generation by convection in a rotating spherical shell with a minimum of parameters is applied to the Sun. Despite its unrealistic features the model exhibits a number of properties resembling…
The solar coronal heating is a longstanding mystery in astrophysics. Considering that the solar magnetic field is spatially inhomogeneous with considerable magnetic gradient from solar surface to the corona, this work proposes a magnetic…
Photovoltaic conversion is highly dependent on the converter's temperature. In the absence of atmosphere, it can be rigorously determined using a thermal balance leading to a compact expression. The derivation starts from a fully spectral,…
We present a series of numerical simulations of the quiet Sun plasma threaded by magnetic fields that extend from the upper convection zone into the low corona. We discuss an efficient, simplified approximation to the physics of optically…
This question, which often comes in when discussing solar neutrinos, is not clearly analysed in any textbook, to our knowledge. In this note we give a simple estimate of the flow time, also reminding its (ir)relevance to the solar neutrino…
The interplay between quantum-mechanical properties, such as coherence, and classical notions, such as energy, is a subtle topic at the forefront of quantum thermodynamics. The traditional Carnot argument limits the conversion of heat to…
We propose in this article a method to generate radiative coolers which are reflective in the solar spectrum and emissive in the transparency window of the atmosphere (8-13 $\mu$m). We choose an approach combining thermal control capacity…
Although near-field radiative heat transfer was introduced in the 1950's, interest in the field has recently revived, as the effect promises improved performance in various applications where contactless temperature regulation in the…