O Ευθύμιος Βαζαίος έχει δημοσιεύσει πολλές εργασίες και μελέτες σχετικά με την Ηλιακή Ενέργεια.
Το βιβλίο του ‘ΕΦΑΡΜΟΓΕΣ ΤΗΣ ΗΛΙΑΚΗΣ ΕΝΕΡΓΕΙΑΣ – ΥΠΟΛΟΓΙΣΜΟΣ ΚΑΙ ΣΧΕΔΙΑΣΗ ΣΥΣΤΗΜΑΤΩΝ’ χρησιμοποιείται ως διδακτική ύλη σε Ανώτερα Τεχνολογικά Ιδρύματα της χώρας.
Today there is a growing interest for photovoltaic water pumping from deep wells. For such photovoltaic systems battery storage could be added, but the alternative choice of using multistage centrifugal submersible pumps with 3-phase motors presents more advantages.
However, for this latter configuration it is necessary to include a DC/AC inverter which not only incorporates a Maximum Power Point Tracker (MPPT), but it is also capable of regulating the motor speed in proportion to the intensity of the in-plane radiation.
In the present work the simulated performance of the 10 KWp EEC [...]
The long term performance of solar heated swimming pools can be predicted by using the utilizability method when glazed solar collectors are used, or the input – output (i/o) diagrams in case of unglazed collectors.
For the utilizability method average monthly values are required. The values of FR(τα) and FRUL for collectors is the result of usual performance tests. For unglazed collectors the UL coefficient has a significant variation, making the utilizability method useless.
In this case the i/o diagrams can be very useful. Such diagrams have been derived for many swimming pools in [...]
In the present work, a theoretical model is presented concerning the various energy fluxes in a solar heated outdoor swimming pool, with a bare or covered surface.
The analysis considers the instantaneous energy balance using actual climatological data, special attention being focused on setting up equations for the calculation of the turbulent heat-mass transfer energy fluxes. Thus, the net heat loss can be calculated under constant water temperature conditions, paving the way for the determination of the needed solar collector heat power and/or conventional heating. A computer program is written and developed to [...]
The present work describes a theoretical model that has been developed to predict the performance of thermosiphon solar domestic water heaters with a heat exchanger in the storage tank (indirect heating), under various load conditions.
The equations describing the operation of the system are numerically treated, and a computer program is written to implement the analysis. Input data include the system design characteristics, the hour-by-hour meteorological conditions and driving forces (sun) and loads.
To check the validity of the model, experimental work has been carried out for such [...]