Abstract:
This study focuses on a life cycle assessment of vehicle integrated photovoltaic solar energy onboard and off-board to save energy, improve economic and environmental aspects of Nissan
vehicles in Ethiopia. Solar energy on-board and off-board, utilizing photovoltaic (PV) is proposed
to be employed for fuel economy, extend driving ranges, reduce greenhouse gas (GHG) emissions,
and ensure better economic value. The objective of this study is to investigate the technological
benefit of vehicle integrated photovoltaic solar energy through the life cycle assessment. The
methodology employed in this work calculated the total area of the NISSAN vehicle used for the
installation of solar PV. To test the sufficiency of the power produced, direct normal irradiance
(DNI) was computed, taking into consideration the factor of shade and wind speed. Two months
of data were collected in Ethiopia (February and July) to assure the economic return on investment
(ROI) value of installing onboard PVs, with everyday data for all systems. The result shows that
the power loss due to the added mass of PV module, mounting, battery, electric motor, and increase
in the frontal area of vehicle ranges from 140.8 W to 156.28 W, and the power generator from PV
ranges from 492.6 W to 759.3 W. The net power gain ranges from 336.36 W to 613.63 W, which
is the difference between power gain and power loss. The findings show that increasing the daily
driving range of a conventional passenger EV from 4 miles to 22 miles by adding on-board PVs
to cover less than half (about 3.261 m2
) of the estimated horizontal surface area of a conventional
passenger EV. Solar energy is utilized based on the vehicle's specifications, location, season, and
total driving time. When fuel costs were below $6.0 per gallon in July, the return on investment
(ROI) of adding PVs onboard with an ICE vehicle during its lifetime ranged from - $50.86 to
$66.61, and in February, it ranged from $42.76 to $252.27. Furthermore, the return on investment
(ROI) adding PVs on-board with plug-in electric vehicles and electric vehicles had negative to
positive values in the range of $48.98 to $135.65 and $45.45 to $154.72 in July, and $56.46 to
$398. The proposed PV installations showed a short payback period of 5.3 years. After PV
installation, specific CO2 saving with PV energy is 470 g/kWh and the CO2 emission avoided is
8701 Kg/Year.
