In one embodiment a solar collector is provided. The collector has a modular heat transfer component, which includes a heat transfer core to heat up a heat transfer fluid. The collector makes use of the heat transfer fluid itself to prevent heat loss through radiation.

A solar radiation absorber element for a thermal concentrating solar power plant is achieved by forming a selective coating on an outer surface of a substrate made from stainless steel, chosen from stainless steels presenting an aluminum content of more than 0.5% by weight. Formation of the selective coating includes a surface treatment step of the substrate, by polishing, and a heat treatment step of the substrate, in an oxidizing atmosphere, in a temperature range included between 550 C. and 650 C. The heat treatment in particular enables at least one intrinsically selective superficial thin layer to be formed on the outer surface of the substrate.

A system including a steam generation system and a chamber. The steam generation system includes a complex and the steam generation system is configured to receive water, concentrate electromagnetic (EM) radiation received from an EM radiation source, apply the EM radiation to the complex, where the complex absorbs the EM radiation to generate heat, and transform, using the heat generated by the complex, the water to steam. The chamber is configured to receive the steam and an object, wherein the object is of medical waste, medical equipment, fabric, and fecal matter.

A solar-thermal conversion member includes a -FeSi.sub.2 phase material. The solar-thermal conversion member exhibits a high absorptance for visible light at wavelengths of several hundred nm and a low absorptance for infrared light at wavelengths of several thousand nm and, as a consequence, efficiently absorbs visible light at wavelengths of several hundred nm and converts the same into heat and exhibits little thermal radiation due to thermal emission at temperatures of several hundred C. The solar-thermal conversion member may therefore efficiently absorb sunlight, provide heat, and prevent thermal radiation due to thermal emission.

A passive solar tracking system to enhance solar cell output is provided. The passive solar tracking system includes a panel having at least one solar cell for solar-to-electric conversion and an actuator that is arranged for moving the panel to provide the variable facing direction of the panel. The actuator is directly driven by light such as sunlight to provide artificial heliotropism-type movements of the panel, so that the panel passively tracks and continuously faces the sun. The actuator may be made from a composite material including a matrix of liquid crystal elastomer material incorporating single-wall or multi-wall carbon nanotubes and an elastic skeleton defined by a 3D polyurethane fiber-network. An actuator housing may be arranged with respect to the actuator for enhancing delivery of stimulus to the actuator. The actuator housing may include a heat collector and a light concentrator for facilitating actuation of the actuator.

In one embodiment a solar collector is provided. The collector has a modular heat transfer component, which includes a heat transfer core to heat up a heat transfer fluid. The collector makes use of the heat transfer fluid itself to prevent heat loss through radiation.