1. Common: the sun shine on the earth, whether land or sea, whether mountains or islands, are everywhere and recent development and use of direct, and goes without mining and transportation.
2. Sound: development and utilization of solar energy will not pollute the environment, it is one of the cleanest energy in today's increasingly serious environmental pollution, and this is extremely valuable.
3. Enormous: Each year the sun reaches the earth's surface radiation equivalent to about 130 trillion t of standard coal, and its total is now the world's largest energy that can be developed.
4. A long time: According to the current estimated rate of nuclear energy produced by the sun, hydrogen storage is sufficient to maintain billions of years, but also about the life of the Earth billions of years, in this sense can be said that the sun's energy is the inexhaustible.
1. Dispersion: solar radiation reaching the Earth's total surface, despite the great, but energy density is very low. On average, near the Tropic of Cancer, sunny summer weather in the case when the noon maximum irradiance of solar radiation in the direction perpendicular to the sunlight area of 1 square meter of solar energy received on average about 1000W; if by the year The average day and night, only 200W or so. Only half or less in the winter, cloudy day to only about 1/5, this energy density is very low. Therefore, when the use of solar energy, want to get some of the conversion power, often require a fairly large area of collection and conversion equipment, higher cost.
2. Instability: due to the day and night, season, geographic latitude and altitude and natural conditions such as sunny, cloudy, clouds, rain and other random factors, therefore, at a certain ground is both intermittent solar irradiance, is very unstable, giving large-scale application of solar energy more difficult. To make solar energy a continuous, stable energy, which eventually become able to compete with conventional energy sources alternative energy, energy storage to be a good solution to the problem, that is fine as far as possible during the day and store up the solar radiation, for the night or on rainy day use, but also the use of solar energy storage in one of the more weak links.
(3) Low efficiency and high cost: the current level of development of solar energy utilization, in some respects it is feasible and technically mature. However, some solar energy installations, because the low efficiency, high cost, in general, economy can not compete with conventional energy sources. Considerable period of time in the future, further development of solar energy, mainly by economic constraints.