The direction of the development of solar energy have which a few respects1

Solar water heater, solar street light, solar cells and so on is inseparable from the energy from the external object of earth & ndash; — Solar energy. Approaches of the development of solar energy has the following aspects:

solar-thermal use: its basic turns out to be the sun radiant energy collected, through the interaction with the material is converted into heat energy. Currently the most used solar collectors, mainly flat-plate collectors, vacuum tube collectors and focusing collectors 3 kinds. Usually based on the can reach temperatures and different purposes of, and divides into the solar-thermal use used at low temperature ( < 200℃) , medium temperature ( 200～800℃) And high temperature use ( > 800℃) 。 Currently used at low temperature are mainly solar water heater, solar dryer, distiller, the sun room, solar greenhouse, solar air-conditioning refrigeration system, such as medium temperature using mainly include solar oven, solar thermal power generation concentrated heating device, etc. , use high temperature mainly include high temperature solar cookers and so on.

photochemical use: this is a direct decomposition of hydrogen production from water using solar radiant energy light & ndash; Chemical transformations.

solar power: large-scale use of solar energy in the future is used to generate electricity. There are many means of using solar power. Now basically has the following two kinds of practical. Light & ndash; Hot & ndash; Electricity conversion. It is using solar radiation generated by thermal power generation. General is to use the heat energy absorbed by the solar collector will of substance is converted to steam, and steam turbine driven by a steam driven generator to produce electricity. The previous process for light & ndash; After thermal conversion, process for hot & ndash; Electricity conversion. Light & ndash; Electricity conversion. Its basic principle is to use photovoltaic effect to convert solar radiation directly into electricity, it is the fundamental unit of solar cells.

creatures use light: through plant photosynthesis used to implement a process to convert solar energy into biomass. At present there are fast-growing plants (mainly Such as firewood forests) , oil crops, and giant algae.

although the total solar energy resources is equivalent to more than ten thousand times the current energy use by a human, but solar energy density is low, and it varies from place to place, due to the circumstances, it is a major problem faced by the development and utilization of solar energy.