A Solar Energy Resources Assessment In Dongying

Because the conventional energy reserves are limited and furthermore their consumption will release large harmful substances and pollute the air, so many countries have regarded the development and utilization of the solar energy resources as one of the important industry for maintaining a sustainable socio-economic development. The solar energy resources can generally be utilized by the way of photethermal conversion, photoelectric transition, bioconversion and photochemical conversion. Meanwhile, for a better utilization of solar energy resources with a good scientific basis, a lot of research studies have been carried out. In order to promote the efficient use of solar energy resources, reduce the consumption of non-renewable energy resources such as oil and coal, and meanwhile provide a theoretical guidance for the development and utilization of solar energy resources in Dongying city, it is necessary to carry out a study of solar resource assessment.By using the data of sunshine duration, percentage of sunshine, monthly total astronomical solar radiation and other meteorological measurements from1981to2010in Dongying, and the solar radiation observations from1961to2010in Fushan at the location very near Dongying, firstly, the climate characteristics in Dongying is analyzed and discussed. Secondly, the regression equations were then established between the amount of the solar radiation and percentage of sunshine based on the observations in Fushan and further tested by using the different data at other observational period. Thirdly, the amount of total solar radiation in Dongying for each year from1981to2010was estimated based on the regression equations in Fushan, the data of monthly total astronomical solar radiation and percentage of sunshine in Dongying. Finally, the abundance of solar energy resources, the stability of solar energy resources and the time period for the best use of solar energy resources in Dongying were evaluated based on above calculated results. The main results were as follows:(1) There are large differences between the monthly averages of the solar radiation with the maximum of626.9MJ/m2in May and the minimum of235.9MJ/m2in December; the average of total solar radiation from1981to2010is5188.0MJ/m2with the maximum of5603.1MJ/m2in1982and the minimum of4804.9MJ/m2in1998. Therefore, there are very rich solar energy resources in Dongying. However, the amount of solar radiation in Dongying is less than in land area at the same latitude.(2) The average number of days with the sunshine duration larger than6h is208, the annual average of sunshine duration is2632.7h, and the daily average of sunshine duration is7.2h. Therefore, the utilization value of solar radiation resources in Dongying is relatively high.(3) The ratio between the maximum number and minimum number of days with the sunshine duration larger than6h is1.5so the solar radiation resources in Dongying are stable.(4) The average of annual total solar radiation from11to13LT is1420.29MJ/(m2·a) and the average of annual total scattered radiation is544.86MJ/(m2·a) so the time period for the best use of solar energy resources in Dongying is between11and13LT.Finally, the four ways of utilizing the solar energy resources in Dongying were proposed:(1) the sun room, including active and passive ways;(2) the vacuum tube collector;(3) solar power, mainly including light-heat-electricity conversion and light-electric conversion;(4) photochemical use and light use, etc.