Heat energy measurement device for solar energy hot water storage tank

摘要

The device (3) involves a heat storage tank (1) which has a sensor (2) arranged parallel to its longitudinal axis which integrates the temperature over the tank height. An alternative arrangement uses a Z-shaped sensor along the outer surface of the tank. A resistance bridge (3) shows the electrical resistance of the measurement sensor (2) and this together with the volume of the tank can be converted to the heat energy contained in the tank, either as a reading in Joules or as a percentage of maximum value. The sensor is an electrically conducting wire such as copper which is in thermal, but not electrical, contact with the container wall. The resistance change is proportional to the temperature change of the container wall.