Civil Engineering Reference
In-Depth Information
occurs between 0.05 and 0.1 m for this system. This type of PV/T system was
practical and cost-effective, suitable for being integrated into the building with
both heat and electrical demands.
Solanki et al. (
2009
) designed and constructed a PV/T solar air heater and
studied its performance over different operational parameters under steady indoor
conditions. Experimental simulator consisted of three PV modules (mono-crys-
talline silicon solar cells) of glass to tedlar type, each rating at 75 Wp, has 0.45 m
width and 1.2 m length and was mounted on a wooden duct. They found that the
thermal, electrical and overall efficiency of the solar heater obtained at indoor
condition was 42, 8.4 and 50 %, respectively. They also proposed an indoor
standard test procedure for thermal and electrical testing of the PV/T collectors
connected in series. It is concluded that this test procedure can be used by man-
ufacturers for testing different types of PV modules in order to optimise its geo-
metrical sizes.
Shahsavar and Ameri (
2010
) designed and tested a direct-coupled PV/T air
collector with and without glass cover at Kerman, Iran. In their study, a thin
aluminium sheet suspended at the middle of air channel was used to increase the
heat exchange area and consequently improve heat extraction from PV panels.
This PV/T system was tested in natural forced convection conditions (with two,
four and eight fans operating). Good agreement between the measured values and
those calculated by the simulation model was achieved. It is concluded that there is
an optimum number of fans for achieving maximum electrical efficiency. Also,
results showed that setting glass cover on photovoltaic panels leads to an increase
in thermal efficiency and decrease in electrical efficiency of the system.
Huang et al. (
2003
) studied an integrated photovoltaic-thermal system set-up.
A commercial polycrystalline PV module was used for making a PV/T collector,
which is part of the system configuration. The testing approach for conventional
solar hot water heaters was used to evaluate the thermal performance rating of the
system. The tested results showed that the solar PV/T collector made of a corru-
gated polycarbonate panel can obtain a primary-energy-saving efficiency of about
61.3 %, while the temperature difference between the tank water and the PV
module was around 4 C.
De Vries (
1998
) and Zondag et al. (
2002
,
2003
) carried out testing of a PV/T
solar boiler with a water storage tank in the Dutch and found that the covered
sheet-and-tube system was the most promising PV/T concept for tap water heating.
It reported that the water-based PV/T system can provide more architectural
uniformity, minimise the usage of space on roof and achieve reduced payback
period. This PV/T system could achieve annual average solar efficiencies of
between 34 and 39 % for the covered designs and 24 % for the uncovered design.
Chow et al. (
2006
) illustrated an experimental study into a combined centra-
lised photovoltaic and hot water collector wall system that can serve as the water
preheater. The collectors were mounted at vertical facades, and different operating
modes were implemented for different seasons. They found that natural water
circulation was preferable to the forced circulation in this hybrid solar collector
system. The thermal efficiency was reported 38.9 % at zero reduced temperature,
