The invention relates to a hybrid solar collector that generates thermal and electrical energy while maintaining a comfortable indoor climate. The hybrid solar collector comprises a thermal energy collector for time-delayed transfer of thermal energy resulting from incident solar energy into building walls having a rear-vented cover arranged so that an air gap is formed between the solid collector portion and the cover, said cover comprising photovoltaic (PV) elements and being at least partially transparent and/or partially translucent so as to allow solar radiation to impinge on the solid thermal collector, wherein the air in the gap between the cover and the collector is sucked by a heat pump preferably for use in heating water or thermal storage The hybrid solar collector of the invention stores thermal energy in and releases thermal energy from the thermal collector portion, while also generating electricity using the PV elements and utilizing thermal energy from the heated air in the air gap. Operating procedures include targeted air flow and heat recuperation. The system may be used to retrofit existing thermal solar cells with incident-angle-selective structure.

A parabolic trough solar collector include a parabolic trough reflector extending in a longitudinal direction; and a frame supporting the reflector, the frame comprising at least one truss extending perpendicular to the longitudinal direction, the at least one truss comprising a plurality of wooden members connected at a plurality of joints, wherein: a first wooden member has a stiffness SWM1, a second wooden member has a stiffness SWM2, and a first joint that connects the first wooden member and the second wooden member together has a stiffness SJ1, and wherein: SWM12SJ1, and SWM22SJ1.

The present disclosure is directed to steam generation through the efficient harvesting of solar energy. In particular, the present disclosure is directed to bilayered structures that are cost-effective, scalable and/or biodegradable that provide high steam-generation efficiency.

The invention relates to a hybrid solar collector that generates thermal and electrical energy while maintaining a comfortable indoor climate. The hybrid solar collector comprises a thermal energy collector for time-delayed transfer of thermal energy resulting from incident solar energy into building walls having a rear-vented cover arranged so that an air gap is formed between the solid collector portion and the cover, said cover comprising photovoltaic (PV) elements and being at least partially transparent and/or partially translucent so as to allow solar radiation to impinge on the solid thermal collector, wherein the air in the gap between the cover and the collector is sucked by a heat pump preferably for use in heating water or thermal storage The hybrid solar collector of the invention stores thermal energy in and releases thermal energy from the thermal collector portion, while also generating electricity using the PV elements and utilizing thermal energy from the heated air in the air gap. Operating procedures include targeted air flow and heat recuperation. The system may be used to retrofit existing thermal solar cells with incident-angle-selective structure.

A modular-sequential-high-temperature heat collection and storage device with integrated power conversion unit.