REVIEW PAPER ON THERMAL PERFORMANCE INVESTIGATION OF EVACUATED TUBE HEAT PIPE SOLAR COLLECTOR WITH NANOFLUID

India is among the top five destinations worldwide for solar energy development. Flat plate or evacuated tube solar collectors may be used to gather solar energy in a non-concentrated manner for heating and cooling purposes. Due to their high efficiency and cost effective nature, this technology is becoming very popular worldwide and may be used year round, even in high humidity, cold temperatures, and/or generally poor weather conditions. Partly due to their increased efficiency over electric water heating, as of 2010, over 70 million residences worldwide had active installations of this technology. The basic construction of these systems consists of some type of absorption mechanism, a transfer mechanism, and some type of storage. A more efficient modification of this technology is the evacuated tube collector. In this configuration, heat pipes are vacuum sealed into a containment unit. These pipes are then used to transfer heat using a manifold. The evacuated tube construction is often preferred as it is 20–45 % more efficient than flat plate solar collectors, achieves reduced heat loss by mitigating conductive/convective forces via vacuum sealing, uses inexpensive pipes that are durable and inexpensive to replace, and, due to the cylindrical nature of the pipes, tracks the sun passively leading to increased efficiencies at lower costs