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The evacuated tube solar collector with auxiliary electric heater (ETCAEH) was presented for rural heating in this study. The examined building heating system with evacuated tube solar collector was designed and constructed in Jinan city, china. The aim of this study is to analyze the feasibility of building heating system presented. Thermal performance and economic analysis of ETCAEH for rural heating were investigated. The results show that the heating room indoor air temperature can meet heating demand by adopting ETCAEH. Furthermore, ETCAEH used in rural area has applicative enough for their advantages in economy by comparing with coal-fired boiler and air conditioning. It is said that this study will provide guidance for designing and economic feasibility of ETCAEH used in building heating.

This paper presents the design, development and performance evaluation of a compound parabolic concentrator for medium temperature application. In the present study Compound Parabolic Concentrator (CPC) has been used as a non-imaging solar concentrator. A single piece of evacuated tube heat pipe solar collector has been used to collect the solar radiation which is concentrated by the CPC. The condenser of the heat pipe has been directly inserted into the storage tank. The performance of the system has been evaluated for different tilt angles. Different performance parameters such as system thermal efficiency and standard power have also been evaluated in this paper.

The aim of this research is to determine the economic feasibility of a solar thermal system used for Domestic Hot Water and Radiant Floor Heating. A two floor house is modeled to create a thermal load. The system design and thermal analysis is studied using TRNSYS. The technical-economic analysis is performed using Microsoft Excel. The optimal type/number of solar thermal collectors and thermal storage size were determined based on the economic figures. The optimum system configuration for the case of evacuated tube system resulted in 8 collectors using a storage relation of 40 L/m 2 whereas flat plate system resulted in 12 collectors using a storage relation of 50 L/m 2 . The return on investment for the flat plate system was calculated in 9 years and the evacuated tube system resulted in approximately 11 years.

A solar raw petroleum heating system to reduce viscosity of the petroleum for its easier piping transport is introduced in this paper. Some aspects of design and operation are described. Natural gas, oil and water are simultaneously contained in the raw petroleum, which need to be heated during its piping transport. In order to make the system reliable, advanced heat-pipe evacuated tube solar collectors have been used for the solar heating system. Practical operation results have shown that about 30% of daily average natural gas consumption could be saved.

The aim of this work was to evaluate the performance of a 35 kW LiBr-H2O absorption machine driven by 72 m2 heat pipe evacuated tube collector with a gas backup system, by analyzing the COP based on the manufacturer's specifications. The results from this study showed that actual average COP of the system was 0.33 while the maximum and minimum values were 0.50 and 0.17 respectively. These results were obtained based on the average collector efficiency and the solar fraction of 0.55 and at an ambient temperature of 32 °C.

Experimental investigation of the overall performance of solar collectors under local weather conditions as encountered along the eastern coast of the Mediterranean Sea is carried out for two kinds of evacuatedtube solar collectors, namely, the water-in-glass tubes and the heat-pipe designs. An experimental set-up, involving full scale collectors made of a row of 20 evacuated tubes and their tank, and a circulation system with measurement tools, was constructed and used. The experiments were carried out during the period of November to January, i.e. under winter-like conditions, at days where the sky was almost clear with some clouds scattered here and there. The results show that the heat-pipe-based collectors are better than the water-in-glass designs and their efficiency is almost 15 to 20% higher. Their payback periods are however, much higher owing to their larger initial cost in the local market.

SiO 2 antireflective nanoporous films were prepared by sol-gel process, combined with dip coating technology. The highest values of solar transmittance (96% in the broader spectrum range of 250 nm-2500 nm) are obtained. The static contact angle values increase after the treatment with 100% ethylchlorosilane and hexamethyldisilazane solutions. The antireflective films has to display long term stability as the operation conditions in solar collectors include low temperatures, high temperatures, and humid environment, all of which can degrade its optical properties.

A novel geometry ICPC evacuated tube solar collector was developed at the University of Chicago and Colorado State University in 1993. Individual evacuated tubes of this novel geometry ICPC were experimentally fabricated and tested at Colorado State University in 1994-96 and at the University of Chicago in 1996-97. In 1998 two 14 tube modules were tested on Sandia National Laboratory's two-axis tracking (AZTRAK) platform in Albuquerque New Mexico by Sandia National Laboratory and the University of Chicago. A 336 tube 100 m2 array of this collector has been in continuous operation at a demonstration project in Sacramento California since 1998. From 1998 to the present performance of the Sacramento demonstration array and single and double effect cooling systems has been monitored and evaluated by the California State University at Sacramento and Colorado State University. Optical ray tracing modelling, thermal performance modelling and collector reliability studies have been conducted by Colorado State University during the 1998 to 2013 period. Performance approaching the theoretical predictions was achieved for the individual ICPC evacuated tubes experimentally fabricated by Colorado State University and the University of Chicago. While operating in the range of 120 to 160C, daily solar collection efficiencies of nearly 0.50 and instantaneous solar collection efficiencies of about 0.60 were achieved. Daily cooling COPs of 1.1 were achieved while operating the double effect chiller with energy supplied from the ICPC solar collectors. A ray tracing simulation incorporating ray transmittance and translation, the gap between the glass tube and fin, reflectivity of the reflective surface, absorptivity of the fin and blocking and displacement of the rays by adjacent tubes has been developed. Animation of individual rays and associated summary graphics and an optical and thermal performance model of the collector have also been developed. Performance of the novel ICPC solar collector at various specified angles along the transverse and longitudinal evacuated tube directions was experimentally measured on the Sandia National Laboratory's two-axis tracking (AZTRAK) platform. Data from the Sandia tests was used to validate the ray tracing simulation performance. Data from the initial operation of the Sacramento array were used to further validate the ray tracing simulation and thermal modelling. The primacy of the two identified collector reliability failure modes was established. Details of the various testing and research activities and results are presented. Animations of the ray tracing are also included in the oral presentation.