Energy Reports 10 (2023) 2740–2755

Contents lists available at ScienceDirect

Energy Reports
journal homepage: www.elsevier.com/locate/egyr

Research paper

Techno-economic and environmental estimation assessment of

floating solar PV power generation on Akosombo dam reservoir in
Ghana
∗
Mohammed Okoe Alhassan a,b , Richard Opoku b,c , Felix Uba d,e , , George Y. Obeng b ,
Charles K.K. Sekyere b , Peter Nyanor b
a
Department of Mechanical Engineering, Takoradi Technical University, P.O. Box 256, Takoradi, Ghana
b
Department of Mechanical Engineering, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
c
The Brew-Hammond Energy Center, College of Engineering, KNUST, Ghana
d
Department of Mechanical and Manufacturing Engineering, University of Energy and Natural Resources, Sunyani, Ghana
e
Regional Centre of Energy and Environmental Sustainability (RCEES), UENR, Ghana

article info a b s t r a c t

Article history: Ghana has developed energy policies to help increase the use of renewable energy in its energy mix.
Received 9 May 2023 With abundant water reservoirs and solar irradiation, the potential to deploy floating solar photovoltaic
Received in revised form 15 August 2023 is feasible to increase the country’s renewable electricity generation. RETScreen Expert software was
Accepted 11 September 2023
used for studying a proposed FPV-Hydro hybrid plant system. This study conducted a feasibility
Available online 22 September 2023
analysis for a 420 MWp FPV on Akosombo Dam reservoir a location with 4.66 kWh/m2 /day solar
Keywords: energy. The study recommended FPV power plant with capacity factor of 14.1%, and would consist
Floating Solar Photovoltaic (FPV) of 500,000 units of solar panels covering a minimum area of 2,460,457 m2 to generate a total annual
Evaporation electricity of 520,233 MWh. The project will save 73,327 cubic metres of water from evaporating which
RETScreen Expert can produce approximately 10 MWp hydroelectric power annually. FPV economic analysis shown that
Hydropower it will results in lower LCOE of US$ 0.10/kWh, annual revenue of USD $52,238,576.00 and 12-years
Renewable Energy (RE) simple payback time, indicating positive economic indicators. Additionally, it will significantly reduce
GHG emissions by 308,904.5 tCO2 /MWh annually. The FPV-Hydropower hybrid plants prove feasible
and contributes to a greener and less costly energy generation system to meeting the 10% additional
Renewable Energy (RE) target of Ghana.
© 2023 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND
license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

1. Introduction measures, has resulted in a worldwide reduction of toxic emis-

sions from fossil-fuel sources (Gunfaus and Waisman, 2021; Zhao
Better living standards and economic development is globally et al., 2020; Opoku et al., 2018; Ahadzie et al., 2020). Global re-
dependent on access to energy because of their positive rela- gions such as Ghana are exploring RE alternative energy sources,
tion (Qi et al., 2021; Opoku et al., 2020b). Meeting the global such as; bioenergy, hydro, solar and wind for electricity gen-
energy demand must be sustainable as it is critical for industri- eration (Huld and Commission, 2014). Amongst the RE sources,
alization and growth. For the past several years, energy demands solar PV electricity generation systems with appreciable solar
irradiation levels (>13 MJm2 /day) are proving as cost competitive
at the global, regional and national levels have been increasing.
compared with utility grid powered systems from fossil-fuelled
For example, total electricity demand globally increased by 2.3%,
systems, due to its energy market value for domestic and industry
reaching 26,100 TWh in 2018 (Philip et al., 2019). About 65.3%
applications (Opoku et al., 2020a). For the past decade, prices
of the energy generated are from conventional fossil fuel sources,
of solar PV panels have dropped significantly, increasing instal-
which are harmful to the environment leading to climate change lation rate for both residential and commercial sectors, which
issues (IEA, 2019; Global Energy Review 2020, 2020). has promoted clean energy technologies and significantly helped
Global investments in low-carbon energy transformational op- to improve the adverse impact of global climatic variation (Rauf
tions, such as renewable energy (RE) as strategic sustainability et al., 2019; Teixeira et al., 2015).
Most solar PV power plants in Sub-Saharan Africa are ground-
∗ Corresponding author at: Department of Mechanical and Manufacturing mounted and consumes large areas for installation (Hove et al.,
Engineering, University of Energy and Natural Resources, Sunyani, Ghana. 2020). Increasing concern of deforestation for solar PV instal-
E-mail address: felix.uba@uenr.edu.gh (F. Uba). lations coupled with land competition for crop production and

https://doi.org/10.1016/j.egyr.2023.09.073
2352-4847/© 2023 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-
nc-nd/4.0/).
M.O. Alhassan, R. Opoku, F. Uba et al. Energy Reports 10 (2023) 2740–2755

estate developments, creating the need to develop and deploy globe. Some of these notable related studies reviewed, are sum-
new technologies such as floating solar PV (FPV) systems (Sahu marized and presented in Table 1. The literatures show there
et al., 2016). FPV shares several advantages over ground mounted have been many studies regarding individual reservoirs/dams,
PV installations. Floating PV tends to be about 11% more per- ponds and lakes, and supported by different models on floating
formance efficient than the land-based solar panel as a result PV systems performance with significant interest, as effective
of the temperature reduction effect in water (Monforti-ferrario means to meet increasing energy needs for industrialization.
et al., 2016; Ates et al., 2020). Performance of PV systems are Despite the benefits, few studies such as Gonzalez Sanchez
reduced when panel thermal stress is high due to high tempera- et al. (2021), Moner-girona et al. (2021) conducted review works
ture coefficient. In other words, the floating PV is advantageous assessing floating solar photovoltaics potential in existing hy-
in terms of land and water conservation, environmental aspect dropower reservoirs in Africa. Little research has been conducted
(algae formation), as well as less panel cleaning and mainte- in the Sub-Saharan Africa, particularly in countries like Ghana
nance cost due to absence of dust. Due to this benefits, FPV where utility-capacity floating PV systems will be installed in
systems installed on water-bodies, such as lakes, reservoirs/dam the long term. Henceforth, the PV potential of available water-
and ponds, have significant already been deployed across regions bodies in Ghana should be assessed. The already existing studies
and increased globally. Worldwide installed capacity for FPV has for Ghana focused mainly on land-based PV performance tech-
increased significantly with enormous technological growth since nologies (Aboagye et al., 2021a). Although, in Ghana, there is
2016 (Farfan and Breyer, 2018; Lee et al., 2020). an installed 5MW floating solar plant, which forms part of a
However, implementing this FPV technologies requires care- 250 MWp solar energy generation project at Bui hydropower site,
ful consideration of the available technical, economic and envi- making it the first to be commissioned in the sub-region, and
ronmental impacts. Therefore, there is a need for a robust and Ghana’s first hybrid plant utilizing both solar and hydro resources
effective feasibility and system performance approach that can to generate and supply power to the national grid (Bui Power,
prioritize its technological resources for sustainable electricity 2019). This hydro-solar PV hybrid (HSH) system within the Bui
generation. enclave is aimed at augmenting the country’s peak hours and pre-
Presently, studies on the performance of installed floating serving the Bui reservoir. Despite Bui floating PV installed project,
solar PV (FPV) power generation technologies conducted to im- there are no feasibility studies on FPV generation performance
prove its utilization exist in literature. For instance, Durkovic and in the open literature for Ghana that focus on employing hybrid
Djurisic (2017) investigated the environmental impact of a large- solar FPV-hydro systems for electricity generation.
scale floating photovoltaic power system in Montenegro. Their Ghana, a country located in Sub-Saharan Africa, experiences
study showed significant reduction in CO2 emissions of about significant levels of solar radiation throughout the year, hence,
83.42 ktons CO2 /year, water evaporation savings of about 5.41 has excellent potential for FPV installation on other two of its hy-
million m3 /year. In addition, the study showed that Montenegro dropower reservoirs (Akosombo-Black Volta dam reservoir, and
PV plant’s efficiency could be maximized by 16% (IRR = 16%) at Kpong river) and also to expand the existing Bui floating solar
recommended power plant consisting of 18 plants to generate generation on the Black Volta. In spite of all this, the country
a total 90 MWp installed power. Kim et al. (2019) explored heavily depends on fossil-fuels sources to generate electricity to
the possibility of installation FPV in Korea to give 2932 GWh meet the countries-based load. Resulting in high energy costs,
power. In addition, greenhouse gas (GHG CO2 ) emission analysis toxic carbon emissions. Additionally, vast farm lands are also
showed an estimated annual reduction of 1,294,450 tons per wasted for PV plant installations. Currently, the installed RE ca-
year. Another study conducted by Rauf et al. (2020) explored pacity in the country stands at 42.6 MWp as at June 2020 (Energy
the potential of hybridized ‘hydropower-FSPV’ for a small dam Commission of Ghana, 2020a). In view of this, the government
in Pakistan. These studies analysed the performance of a 500 of Ghana launched a campaign with policies and programmes to
kV, 132 kV and 11 kV voltage levels for the combined inte- explore renewable energy projects in with the target of increasing
gration of hydroelectric power and FSPV plant, implementing Renewable Energy (including FPV systems) mix by 10% by 2030
and incorporating an optimization model to maximize power to help achieve the Sustainable Development Goals of the United
output and reach peak demand, to analyse the plants technical Nations. Research has shown that when 3%–4% hydroelectric dam
feasibility. The results proved an additional 3.5% power output reservoirs area are used for solar power generation, it signifi-
for the combined operation for the combined system consisting cantly improve the generation mix and help reduce energy costs
of hydroelectric and 200 MWp FSPV. However, the study does and improve PV sustainability (Energy Commission of Ghana,
not provide any economic or environmental views. The study 2020b). The Akosombo Hydropower station is located on Volta
concluded that, the project could provide additional electricity Lake with a surface area of 8500 km2 . Yet, FPV-hydro technology
and reduce the need for new hydroelectric generators. Other on the Akosombo Volta lake has not been exploited. Adopting
studies revealed that power plants with FPV capabilities could this hybrid system technology will significantly enhance the cost
prevent up to 74 billion m3 of water loss, increasing water ac- efficiency of solar energy in the country with upfront benefits to
cessibility estimated at 6.3 per cent, which would further benefit the nations clean energy campaign, addressing climate change
reservoir-based hydropower production from FPV plants, by an and its hostile impact on socio-economic growth. In view of
estimated 142.5 TWh (Ates et al., 2020). Furthermore, a study in this, assessing this feasibility can provide insights into how ef-
Ref. Goswami and Kumar (2021) implemented a 10 MW FSPV fectively solar irradiation and dam reservoir areas translates into
project, they considered the technical and economic parame- useful electricity, to provide a vital benchmark for FPV system
ters to perform the feasibility analysis. The results showed that optimization.
the FSPV system could generate approximately 10.2% more elec- Therefore, this study introduces RETScreen Expert and Google
tric power than land-based PV plants system. As a result, the Earth program to evaluate the feasible PV electricity performance
levelized-tariff cost of FSPV is then reduced to 39% than other from specific water body coverage respectively. The purpose of
types of PV plants. this study is to evaluate the feasible applicability and potential of
Moreover, several authors have rationally applied various model floating PV on the large Akosombo hydroelectric dam reservoir in
techniques to assess the technical, economic and environmental Ghana.
feasibility of installed floating solar PV (FPV) and hybrid systems This study’s main objective is to conduct technical, environ-
power generation performances in diverse countries, across the mental and financial opportunities of integrating FPV into the
2741
M.O. Alhassan, R. Opoku, F. Uba et al. Energy Reports 10 (2023) 2740–2755

Table 1
Summary: Related studies on model techniques for FPV plants performance.
Author(s) Detail of the study Method/ Technique type Location
Liu et al. (2017) The study examined the effect of cooling and temperature variation on finite element model China
the FPV performance. According to their findings, about 160 GW of
power can be generated from a reservoir with 2500 km2 surface area.
Liu et al. (2019) These studies proposed and analysed, a combined operation of a 2 GW Genetic Algorithm China
FSPV plant and 1 GW pumped storage power (PSP) system performance
to achieve maximum power efficiency and minimum power imbalances.
The experiment operation outcomes illustrated an improved power
output as 9112.74 MW and the reduced energy imbalance as 23.06 MW.
®
Oliveira-pinto and This study analysed FSPV performance implementation using simulation PVsyst model Brazilian
Stokkermans (2020) models to analyse the technical and economic feasibility. Results from
the study showed 1.81%–2.59% increase in power output and
significantly reduced costs.
Golroodbari et al. The study performed a Techno-economic analysis of a hybrid FSPV Mathematical model Netherlands
(2021) plant and a wind farm incorporating cable pooling to enhance solar
capability. The study outcome shows that the combined operation
lessens cost with improved efficiency. They also worked on solar and
wind resources’ effects on power generation.
Yashas and Aman This study analysed floating solar photovoltaic (FSPV) technology to RETScreen, PVWatts, India
(2022) harness sustainable energy, considering 32 lakes spanning across 3294 PVGIS
ac of lake area, assess solar electricity generation output and estimate
water evaporation losses. The study shows that the FSPV systems with
a coverage ratio of 0.5–0.6 could meet an average of 26% of the city’s
annual power demand.
Sukarso and Kim In this study, the authors predicted FPV efficiency and measured energy remote sensing method Indonesia
(2020) yield from the system while also developing an economics analysis on SAM software
an FPV project by comparison with ground-based solar PV (GPV). The
study results show the lake has a cooler temperature than the ground,
with an annual difference of around 8 ◦ C. FPV efficiency was also
shown to be around 0.61% higher than GPV in terms of the prediction.
FPV economic parameter comparison also resulted in 3.37 cents/kWh
lower levelized cost of electricity (LCOE), and 6.08% higher internal rate
of return (IRR) compared to GPV in the base scenario.
Semeskandeh et al. This study evaluated a techno-economic-environmental feasibility MATLAB Simulink and Iran
®
(2022) performance to construct a 5-kW FPV and ground PV (GPV) power RETScreen software
plant. Additionally, the FPV system is compared with the ground PV.
Effects of wind and water temperature were considered in the model.
Also, a sensitivity analysis was performed due to the uncertainty in
climatic conditions. The simulation results showed an FPV system
production capacity and panels’ efficiency of 19.47% and 27.98% higher
than the those of the GPV system. In addition, the FPV system was
found to have a 16.96% increase in the annual performance ratio.
Overall, the FPV system reduces the equity payback to 6.3 years (a
22.2% reduction compared to the GPV power plant).
Febrian et al. (2023) This study performed Floating PV power plant performance with power RETScreen Expert model Indonesia
capacity of 145 MWp Cirata Reservoir using different types of solar
panel. The study results showed an annual energy capacity for
monocrystalline, polycrystalline, and thinfilm solar cell module types as
190.54 GWh, 190.54 GWh, and 186.87 GWh respectively. With capacity
factors of monocrystalline, polycrystalline, and thin-film solar cell
module types respectively of 15.00%; 15.00%; and 14.70%.
Mittal et al. (2017) This study evaluated the feasibility performance of installing FPV RETScreen Expert model India.
system at Ana Sagar Lake (Ajmer), Kaylana Lake (Jodhpur), Kishore
Sagar Lake (Kota), and Man Sagar Lake (Jaipur). From the work AC
energy produced by FPV system, by covering 5%, 10%, 15%, and 20% of
lake’s area are calculated for each of the lakes. Additionally, savings in
water by reduction in evaporation due to FPV estimated. The outcome
of the study shows that the potential of FPV system is highest for Man
Sagar Lake (Jaipur) followed by Kaylana Lake (Jodhpur), Ana Sagar Lake
(Ajmer), and least for Kishore Sagar Lake (Kota).

Akosombo hydroelectric reservoir on the Volta Lake in Ghana, The study’s remaining sections are as follows: Section 2 presents
for energy savings, systems reliability, financial savings, and GHG the materials and methods and employed to achieve the research
emissions mitigations in Ghana. Additionally, this study can con- goal. Likewise, Section 3 highlights on the results and discussions,
tribute to feed-into the target of developing sustainable energy- then Section 4 provided conclusions comments on the study’s key
mix policies by 10% by 2030 to promote RE sources in Ghana. findings.
2742
M.O. Alhassan, R. Opoku, F. Uba et al. Energy Reports 10 (2023) 2740–2755

Fig. 1. Akosombo hydropower dam and reservoir site in Ghana (Google Earth, 2021).

Table 2 Hydroelectric power generation heavily depends on water lev-

Dam site geological data. els and flow in the dams. From Fig. 2, it can be deduced that
Parameter Unit Climate data value the yearly electricity generation was not consistent and cre-
◦
Latitude N 6.1 ates huge energy deficit gap, hence the need for a hybrid solar
◦
Longitude E 0.1 PV-hydro system to serve as a sustainable energy fill to this
Elevation m 19
Heating Design Temp. ◦
C 20.7
energy gap. This yearly electricity generation deficit challenge
Cooling Design Temp. ◦
C 31.0 can be largely attributed to weather instability, such as high
Climate zone – 0A – Extremely – hot – Humid daily temperatures, contributing to evaporation reservoirs. The
propose hybrid system uses abundant solar radiation and the
waterbodies available to produce energy (IEA, 2019). As at the
time of the study there was no environmental information about
2. Materials and methods
the location. To resolve this situation, RETScreen Expert software
(Anon, 2023) was accessed to retrieve recent solar resource data
This section highlights the approaches used to conduct the
for Akosombo Dam site. According to Sinha and Chandel (2014),
technical, economic, and environmental (emissions) analyses of
the RETScreen Expert provides full meteorological data based
the hybridized FPV – hydro systems. Also, the methodologies used
on specific climatic location. Table 3, presents NASAs updated
for estimating the feasible reservoir coverage area are explained. Near Real-time Global Radiation and Meteorological data assessed
from RETScreen Expert for Akosombo.
2.1. Study site description The magnitudes of the values indicate excellent meteorologi-
cal climate conditions for PV energy generation (Aboagye et al.,
Akosombo Hydropower Plant (AHP) dam site is the study 2021b) with an average yearly radiation of 4.66 kWh/m2 /day. In
area, and with a capacity of about 153 × 109 m3 , and it pro- addition, Table 3 indicates the monthly average variance in rel-
vides different services for the inhabitants around; from fishing ative humidity (Hr). The Hr values reported declines throughout
to navigational purposes. The area is also having 4.66 kWh/m2 the hot weather season between November–April, reaching 63.9
of daily solar energy (Fiabge and Obeng, 2006; Gyamfi et al., percent in January. With the onset of the rainy seasons (May–
2015). The facility provides about 38.3% of the bulk of Ghana’s October), Hr rises once more, peaking at 85.6 percent in June
electrical power. The feasibility of the floating solar PV-hydro and July. At the Akosombo Hydro site, the yearly average of Hr is
system was conducted for Akosombo dam site using satellite data 77.9%. In this study, the climate data shows that when Hr is 65.5
recorded from RETScreen database. Table 2 indicates the dam Site percent, the ambient air temperature reaches 28.6 ◦ C with 3.0 m/s
geological data (Latitude 6.1 ◦ N, Longitude 0.1 ◦ E). additionally, air speed, depicting better climatic conditions for PV installations.
Google Earth online engine view of the study site presented in
Fig. 1 (Google Earth, 2021).
2.3. The RETScreen modelling
2.2. Akosombo hydropower plant capacity and climatic data of study
site The Renewable Energy Technology Screen (RETScreen) soft-
ware (Chowdhury et al., 2020b) was selected to help carry out
The station currently has electric-power-generating capacity table top simulations for decision for system sizing the energy
of 1020 MW. The generation capacity at 2020 for hydro, solar generation system. The tool was chosen because of its extensive
and thermal generation was 5137 MW which is about 12.2% applications for clean energy decision making studies This sim-
more than in 2018 (Ghana Grid Company Limited, 2020). Fig. 2 ulation application is a one-of-a-kind decision-support tool for
shows the hydroelectric power generation from 2017 to 2020. examining energy generation, pricing, reduction of greenhouse
2743
M.O. Alhassan, R. Opoku, F. Uba et al. Energy Reports 10 (2023) 2740–2755

Fig. 2. Akosombo hydropower generation capacity between (2017–2020).

Table 3
Solar and climate data of Akosombo Volta Lake site.
Month Temperature (◦ C) Relative humidity (%) Daily solar radiation- GHI (kWh (m2 d)−1 ) Wind speed (m s−1 )
January 27.6 63.9% 4.08 2.5
February 28.6 65.5% 4.78 3.0
March 28.1 72.9% 5.06 3.1
April 27.6 78.3% 5.30 3.1
May 26.7 82.7% 5.15 2.9
June 25.5 85.6% 4.67 3.0
July 24.5 85.6% 4.03 3.5
August 24.5 83.2% 4.14 3.6
September 25.1 83.6% 4.73 3.0
October 25.7 84.2% 5.11 2.6
November 26.7 78.8% 4.84 2.3
December 27.3 69.9% 4.06 2.2
Average 26.5 77.9% 4.66 2.9

gas, financial feasibility, risk of different resource combinations them to their accessories were assessed on the Volta Lake. Selec-
for any place on the globe (Chowdhury et al., 2020b). RETScreen tion of portions on the water bodies that can accommodate the
is a Windows-based energy management software program for PV panel is of critical importance especially the floating structure
evaluating energy system performance. like ponton, mooring lines and floaters. Assessment was done
In this study, RETScreen expert was applied to estimate the using images captured and calculated from Google Earth online
FPV plant feasibility performance for technical, economic and engine (Ismail et al., 2022).
environmental on the Akosombo dam reservoir. Simulations were In this study, Google earth program was used to assess and
performed to determine the quantity of PV panels that will fit illustrate the energy production capacities per considered surface
the feasible coverage area for an appropriate FPV design and areas on the Akosombo reservoir. The potential of floating solar
the electricity generation capacity. Climatic data were accessed PV energy production at Akosombo dam site were investigated
for the feasibility performance through RETScreen Expert NASA considering less than o.1% (<0.1) reservoir coverage area. This
database with integrated electricity generated power plants. Ad- study, then uses RETScreen Expert software and applied the sub-
ditionally, RETScreen performed a Monte Carlo simulation for systems (solar panel, inverter, transformer) input parameters into
comparative risk analysis to benchmark FPV source unit energy the model to estimate the reservoir surface area applicable for a
production cost to existing conventional energy sources, to ascer- certain electricity generation. Then, Google Earth software was
tain FPV systems cost-effective production performance against used to demonstrate the effective reservoir coverage area as
the plant capacity. A unit energy production cost of 0.10 $/kWh shown in Fig. 4. The Google Earth online program considered the
from RETScreen simulation was used for the benchmark analysis, Akosombo reservoir depth (maximum lake level: 84. 73 m and
as shown in Fig. 3. minimum lake level: 73.15 m) as a reference input levels for the
underwater ground range, then to perform the water depth map-
2.4. PV module reservoir coverage assessment ping simulation. The simulation was conducted to select feasible
reservoir areas with depths corresponding to the maximum and
Safe zone within the dam boundaries with adequate depth minimum depth range to withstand the simple water variations
that is suitable for the stationing of the panels before attaching as well as flood water levels with no obstacles beneath. This
2744
M.O. Alhassan, R. Opoku, F. Uba et al. Energy Reports 10 (2023) 2740–2755

Fig. 3. Benchmarks of unit energy production cost ($/kWh) of proposed FPV system to other energy sources RETScreen expert.

Fig. 4. Feasible reservoir areas (Yellow Boundary) of 2.46 km2 assessed for the FPV plant capacity in the study. (For interpretation of the references to colour in this
figure legend, the reader is referred to the web version of this article.)

was to ensure the system is able to withstand minimum sag, were then applied to obtain relevant output performance vari-
considered for the floating PV systems anchoring to the waterbed, ables including the annual energy yield, the levelized cost of
and avoiding the floating bed sinking or sagging towards the electricity (LCOE), simple payback time (SPBT), net present value
shore to cause damage to the PV system and power cables. This (NPV), GHG CO2 and water savings, and internal rate of return
online tool has specific characteristics for gauging the underwater (IRR). The floating PV power output was computed using design
ground elevation of a reservoir and measuring border layouts on factors such as solar irradiation, PV panel characteristics (tilt
water bodies. The software helped find the feasible. The feasible angle, module efficiency, module cell temperature, and mod-
simulated reservoir size with adequate depth to install the PV
ule power), inverter efficiency, and panel installation area in
panels was 2.46 km2 , as highlighted in Fig. 4.
RETScreen Expert.
2.5. Modelling FPV-hydro plant system Furthermore, extra hydroelectric power from saved evapo-
rated water was estimated using main hydropower design pa-
Design parameters presented in Fig. 5, were analysed to mea- rameters from Akosombo hydro plant catalogue and adopted
sure the possibility of integrating potential renewable resource available data including dam water level, water flow rate, turbine
like floating PV system into the hydro power station. The tech- efficiency, available hydraulic height, reservoir volume capacity,
nical performance, economic and environmental impact models average discharge ratio of the reservoir (Kougias et al., 2016).
2745
M.O. Alhassan, R. Opoku, F. Uba et al. Energy Reports 10 (2023) 2740–2755

Fig. 5. Design parameters of FPV-Hydropower hybridized plant.

Fig. 5 presented the design parameters implemented in this study. Tamb , NOCT and Gt denote ambient air temperature, average de-
The factors that affect FPV output performance including ambient sign operating cell temperature, at 45 ± 2 ◦ C (I = 800 W/m2 ,
temperature, irradiance levels, cell temperature, panel installa- T = 20 ◦ C @ mair = 1.5) and total irradiance. Table 4 shows the
tion coverage area etc. were assessed. The performance indicators characteristics of the name plate of selected panel.
include solar PV energy output and evaporation.
2.5.2. Evaporation reduction calculation
2.5.1. Modelling solar PV output power performance Reduction in water through evaporation from a reservoir is
RETScreen computes the PV array power output using Eq. (1), a major benefit of FPV to the reservoir (Eshun and Amoako-
based on total solar irradiance at the selected dam site as fol- Tuffour, 2016). Several environmental and climatic parameters
lows (Murat et al., 2020); are necessary when estimating the evaporation rate (Er) from
Eq. (5) (IRENA, 2019).
Pm = Gt Am ηsystem (1) ( )2
√ Rf
Pm , Gt , Am , ηsystem denote module (panel) output power (kW), total Er =0.047Rf 9.5 + Tdm − 2.4
Ret (5)
irradiance (global radiation on the horizontal surface), covered
area of floating PV module (panels) and PV system efficiency. The
+ 0.09 (20 + Tdm ) (1 − 0.01Hr )
FPV plant system efficiency is estimated using Eq. (2), (Murat Er , Tdm , Ret , Rf and Hr denote average daily water surface evap-
et al., 2020); oration (mm/day), mean daily temperature (◦ C), extra-terrestrial
radiation (MJ/m2 /s), radiation flux (MJ/m2 /s) and relative humid-
ηsystem = ηm ∗ ηinverter ∗ ηT ∗ ηcable (2) ity.
ηm , ηinverter , ηT and ηcable denote module efficiency, inverter effi- The amount of water stored as a result of effect of reduced
ciency, transformer efficiency and cable and junction box efficien- evaporation (∆V) (m3 ) is estimated by Eq. (6), (Farfan and Breyer,
cies respectively. A collective value of 0.95 was used to represent 2018).
ηinverter , ηT and ηcable (Murat et al., 2020), while ηm was 0.15 for
( )
Er
a silicon PV panels. Moreover, for temperature-dependent FPV ∆Vw = AFPV ∗ (6)
1000
module efficiency (%), Eq. (3) is used to estimate efficiency of a
PV module (Murat et al., 2020); AFPV denotes surface area of panel covered on water (m2 ).
Wp, (kWh) denotes the maximum electricity energy of the
ηm = ηm,stc [1 − αt (Tc − Ta )] (3) power plant (kWh) that could be generated by the hydroelectric
αt , Tc , Ta , ηm,stc denote PV module temperature coefficient, mod- using the volume of water saved (m3 ) from evaporation, derived
ule temperature of the module, temperature of the PV module at from Eqs. (7) to (10), (Farfan and Breyer, 2018).
T= 25 ◦ C and efficiency of the PV conversion due to the influence WP = η∗ρ∗g ∗ H ∗ Q ∗ T (7)
of the deviation of the PV temperature in relation to the STC
values. Here, module cell temperature (Tc ), is estimated from ϕ
T = (8)
Eq. (4), (Murat et al., 2020); θ
(NOCT − 20o ) ∗ Gt Wp , η, ρ , g, H, Q, T, ϕ , ∆Vw and θ denote maximum electricity
Tc = Tamb + (4) energy of the power plant (kWh), hydraulic turbine efficiency and
0.8
2746
M.O. Alhassan, R. Opoku, F. Uba et al. Energy Reports 10 (2023) 2740–2755

Table 4
Characteristics of the inverter and the PV system.
Solar module Inverter type
Manufacturer: Q-Cells Rated Power Capacity: 90, 000 kW
Model: mono-Si - Q. PEAK BLK-G4.1- 285 W Vmax_mppt: 480 V
Rated power: 285Wp (mono-crystalline silicon) Inverter DC to AC ratio: 0.99
Nominal Efficiency (η): 17.07% Efficiency: 95%
Operating Cell Temperature (NOCT): 45 ◦ C ± 2 ◦ C Miscellaneous Losses: 1%
Temperature Coefficient: 0.4%
Miscellaneous Losses: 16%
Life Expectancy: 25 years
Panel Frame: 1.67 m2

electricity generator in %, (85% was chosen Sinha and Chandel, The LCOE of the FPV was calculated based on the simplified
2014; Kougias et al., 2016), density of water (1000 kg/m3 ), ac- LCOE Eqs. (12) and (13), (Huld and Commission, 2014; Chowd-
celeration of gravity constant, effective net pressure head of the hury et al., 2020a):
dam (m), Water flow (m3 /s), time in hours, reservoir capacity in ∑n It +Mt +Et
m3 , volume of water saved by evaporation (m3 ) and mean annual
t =0 (1+(1+R%)t )
LCOE = ∑n Et
(12)
reservoir discharge (m3 /s) respectively. t =0 (1+R%)t

sum of discounted costs ov er lifetime

LCOE = (13)
2.5.3. Economic performance modelling (financial and cost analysis) sum of discounted energy prov ided ov er lifetime
Energy payback time (EPBT), levelized cost of energy (LCOE), It , Mt , Ft , Et and R% denote capital spending in year t ($), O&M
net present value (NPV), and internal rate of return (IRR) models spending in year t ($), fuel spending in year t ($), energy pro-
were utilized in the economic performance model. The simple duction in year t (MWh) and discounted rate (%), when the t =
payback time (SPBT) present the amount years required for cash projected lifetime of the project system (in yrs.).
flow (except. loan payments) from using FPV energy to match
total investment (equal to aggregate debt and equity), presented 2.5.4. Environmental impact modelling (GHG emission mitigation
in Eq. (9) as Durkovic and Djurisic (2017) was used to derive the potential)
basic payback period: The effect of the FPV system on greenhouse gas reductions.
Ci ($)
(GHG) emission was calculated using Eq. (14) (Durkovic and
Payback (years) = ( ) ( ) Djurisic, 2017; Diawuo et al., 2020; Anane-Fenin, 1986):
(100% − Tax (%)) ∗ Pw kWh $ $
( )
year
∗ yn MWh
− O$M year
( )
tCO2
(9) Gr = Pw ∗ Gs ∗ (1 + β) (14)
MWh/year
Ci , Pw , yn and O$M denote initial cost ($), Annual FPV power pro-
( )
Gr , Gs , P w and β denote annual reduction of GHG,
tCO2
$ MWyearh
,
duction,
( energy charge ( MWh ) and Operational and Maintenance ( )
tCO2
)
cost $
. standard value of GHG emissions for Ghana, MWh
, annual en-
year
When applied to project cash flows, the internal rate of return ergy production ( MWh )
(total potential energy of FPV + AHPD)
year
(IRR) is the discount rate which results in a net present value and a dimensionless parameter of transmission and distribution
(NPV) of zero (NPV = 0). The expected project performance systems average loss.
can then be calculated with that discount rate. The project is
approved if the IRR is more than a predetermined percentage. 3. Results and discussion
Project is rejected when IRR is below target (Chowdhury et al.,
2020b; Ismail et al., 2022). The study’s findings are presented and discussed in this sec-
To calculate the IRR value, Eq. (10) was utilized. tion. It highlights the FPV system’s technical performance, finan-
cial and economic analysis and GHG emission savings. Addition-
NPVa
IRR = Ra + (Rb − Ra ) (10) ally, evaporation savings for electricity generation feasibility was
NPVa − NPVb also assessed.
IRR, Ra , Rb , NPV a and NPV b denote the internal rate of return,
lower discount rate chosen, and higher discount rate chosen, NPV 3.1. Electricity generation of FPV system
@ Ra and NPV @ Rb.
The net present value for the project is computed discounting RETScreen Expert modelling program was used to size and
all cash streams using Eq. (11), (Arjunan, 2019) as: analyse a feasible FPV plant system through multiple input pa-
n ( ) rameters, with the assumption of occupying less than o.1% (<0.1)
∑ CFt of reservoir area, a location with an average annual solar radiation
NPV = (11)
t =0
(1 + r )t of 4.66 kWh/m2/day. The analysis types and methods chosen in
RETScreen are mini grid and method two respectively From Fig. 6,
CF t , r, t and n denote cash flows in the period (n), rate of return, RETScreen simulation input parameters considered includes; 285
time period and total number of periods, respectively. After re- Wp (Q-Cells manufactured) mono-crystalline silicon cell was se-
moving the current investment, the net present value (NPV) is lected for the investigation. Detail information about the solar cell
the current amount of future cash flows returns on investment and inverter specifications is shown in Fig. 6. Results from FPV
that have been discounted to their current value. The target rates system modelling established a plant capacity factor of 14.1% for
put the net present value as close to zero as possible may be the solar collector area of 2,460,457 m2 (2.46 km2 ). An annual
attained by applying the NPV formula and filling in rates (Drury amount 520,223 MWh is produced into the grid from FPV at a
et al., 2011). rate of 0.10 $/kWh. This amount of energy requires a total of
2747
M.O. Alhassan, R. Opoku, F. Uba et al. Energy Reports 10 (2023) 2740–2755

Fig. 6. PV system and inverter input characteristics and parameters in RETScreen expert.

60 arrays, each with a 7 MWp power capacity from 500,000 PV India, Oliveira-pinto and Stokkermans (2020) in Brazil, Liu et al.
panels (1.67 m2 frame area) to be placed within the calculated (2017) in China, and Yashas and Aman (2022), Semeskandeh et al.
area of 2.46 km2 . A total of 420 MWp power was attained for (2022), Febrian et al. (2023) in India, Indonesia Iran respectively,
the system as each array has 7 MWp. Relatively, the estimated where using FPV in electricity generations with RETScreen model.
420 MWp FPV energy is about 10% more than Ghana’s installed The monthly average daily total of energy delivered to grid by
generation capacity from REs in Ghana, at the end of June 2020, the 420 MWp floating PV system, as well as the monthly maxi-
which stood at 42.6 MW. The proposed installed capacity in mum irradiance statistics, are detailed in Fig. 7. Certainly, Fig. 7,
this study is comparatively 41% of the 1020 MWp Akosombo confirms that, output power of solar module increase as irradi-
hydroelectric plant capacity. Moreover, results in Table 5 shows ance increases, which observed the highest electricity generation
the total monthly radiation on a horizontal surface, and the accruing in October, and lowest in July during the raining season.
corresponding electricity exported to the gid-network with the Henceforward, solar PV systems will export 12, 875.77 GWh FPV
export rate of the generated electricity. power into the grid during a 25-year period, considering 1%
From Table 5, the average irradiance of 4.66 kWh/m2 through- system degradation rate (Chowdhury et al., 2020a).
out the year on the Global horizontal irradiance (GHI), with
the lowest and highest concentrations at 4.035.30 kWh/m2 and
5.30 kWh/m2 respectively occurred on July and April followed by 3.2. Cost analysis of FPV system
October. In April, when solar irradiance is high, the FPV system
delivered 47,459.774 MWh of electrical energy to the grid, and Appropriate estimations of cost and financial characteristics
37,800.361 MWh in July. For 0.42 GWp FPV solar power plant, such as the initial cost, yearly capital cost, O&M cost and rev-
520,233.433 MWh is exported into the grid each year. These find- enues, as well as debt payments are analysed in order to assess
ings are comparable with those obtained by Mittal et al. (2017) in the proposed system’s expenses. They are critical in determining
2748
M.O. Alhassan, R. Opoku, F. Uba et al. Energy Reports 10 (2023) 2740–2755

Table 5
Average monthly FPV electricity exported to the grid.
Month Daily solar radiation Electricity export rate Electricity exported Electrical energy
– GHI (kWh/m2 /d) ($/kWh) to grid (MWh) exported to grid (GWh)
January 4.08 0.10 39,877.035 39.88
February 4.78 0.10 41,294.962 41.29
March 5.06 0.10 47,640.334 47.64
April 5.30 0.10 47,459.774 47.46
May 5.15 0.10 47,190.456 47.19
June 4.67 0.10 41,633.695 41.63
July 4.03 0.10 37,800.361 37.80
August 4.14 0.10 39,171.859 39.17
September 4.73 0.10 43,517.245 43.52
October 5.11 0.10 49,098.170 49.10
November 4.84 0.10 45,639.615 45.64
December 4.06 0.10 39,899.927 39.99
Annual 4.66 0.10 520,233.433 520.233

Fig. 7. Solar irradiation and generated energy and delivered by the FPV system to grid monthly.

the proposed project’s economic viability. Conducting cost cal- Table 6

culations using cost parameters in the RETScreen Expert model Initial and annual costs, annual savings of proposed FPV system.
in order to evaluate project viability is vital part of project im- Project initial costs summary
plementation to boost investors’ confidence. The cost estimation Initial costs
presented in Table 6, indicates an initial cost of $ 567,030,000.00 (%) Rate (USD $)
for the project with 99.99% of the cost coming from power system Power system 99.99 567,000,000
sources, acting as the major cost impact of the project. The power Feasibility study 0.002 10,000
Development 0.004 20,000
system sources include factors such as; PV panels, development, Total initial costs 100% 567,030,000
engineering, feasibility study, training and commissioning, invert-
Annual costs
ers, cables, and accessories. The PV and inverter lifetimes were
O&M costs (savings) 5,04,000
estimated to be 25 years in the proposed system, with a max-
Engineering 20,000
imum debt repayment rate of 15 years. The overall yearly cost Training and commissioning 8,000
of the project is anticipated to be USD $48,647,792.00. After all Debt payments-15 years 43,579,792
the expenses, the annual savings and revenue from the project is Total annual costs (TAC) 48,579,792
USD $52, 238,576.00, this includes benefits of GHG reduction rev- Annual savings
enue amount (USD $216,233) (Table 6), demonstrating a viable,
Electricity export revenue 52,022,343
cost-effective and bankable and revenue generating project. GHG reduction revenue 216,233
Total annual savings and revenue 52,238,576
3.3. Financial analysis of FPV system Net yearly cash flow – Year 1 3590784.18

The RETScreen Expert Software allows an operator to enter a

variety of financial scenarios with different data (discount rates),
estimate crucial financial viability indicators (equity payback, shows the features that were employed in this study to conduct a
simple payback, and Net Present Value (NPV)). The outcome for 25-year studies with 2% inflation, which is comparable to average
a typical financial scenario is represented in Table 7. The table, rates as of 2020 (Chowdhury et al., 2020b).

2749
M.O. Alhassan, R. Opoku, F. Uba et al. Energy Reports 10 (2023) 2740–2755

Fig. 8. FPV energy project annual pre-tax cash flows.

Table 7 proposed system’s capacity to reduce greenhouse gas emissions

Financial parameters in the proposed FPV project. (mitigation). The GHG emission reduction was estimated using
Financial parameter Value (units) RETScreen Expert, which analysed the proposed FPV case technol-
Fuel cost escalation rate 1% ogy’s annual emission reduction to Ghana’s present fossil-energy
Inflation rate 2%
technology’s annual GHG emission reduction (base case scenario).
Discount rate 9%
Reinvestment rate 9%
308,904.5 tonnes of CO2 are saved from been released into the
Project life 25 Yrs environment from generating 520,233 MWh yearly electricity
Finance at Akosombo dam site as presented in Table 8. The potential
GHG emission reduction of the proposed FPV project decreases
Incentives and grants $30,000
Debt ratio 70% CO2 emissions by 308,904.5 tCO2/MWh when compared to the
Debt $396,921,000 base scenario as shown in Fig. 10. This 308,904.5 tCO2e is the
Equity $170,109,000 same as 132,727,648.7 litres of gasoline not consumed. Compar-
Debt interest rate 7% atively, the emission mitigation tends to contribute immensely
Debt term 15 yrs
Debt payments $43,579,792/yr
towards a greener and clean environment, and pegged at 2019
Simple payback 12 yrs GHG reduction credit rate of $0.70/tCO2 for Ghana (Diawuo
Equity payback 14.8 yrs et al., 2020), an accumulated annual reduction revenue of USD
Net present value (NPV) $ 32,657,082 $216,233 was achieved. For instance, if the conventional energy
Annual life cycle savings $3,324,695
sources are replaced with Floating PV systems in Ghanaian. These
Energy production cost $/kWh 0.10
results are comparable with those attained by Febrian et al.
(2023), and Semeskandeh et al. (2022) in India and Indonesia
respectively, as deploying FPV would considerably reduce GHG
Similarly, at 9 percent discount rate, a yearly cost for O&M emissions.
was estimated at 1 percent of capital cost (Chowdhury et al., Financial analysis Deployment of FPV technology significantly
2020b). From the annual pre-tax and cash flow diagrams (Figs. 8 will augment Ghana’s ambitious SDGs climate commitments to-
and 9), a positive cash flow was achieved after 14 years with a wards a clean energy agenda. From the analysis the hybrid system
12 years simple payback. It also demonstrated that, a positive is more beneficial (CO2 emission reductions, etc.) over the current
Net Present Value (USD$ 32,657,082) and annual life cycle savings thermal systems run by the country
of US$3,324,695/yr., will be yielded, at an equity payback period
14.8 years. In terms of project economics, the FPV-Hydro hybrid 3.5. Risk analysis of FPV system project
plant system is cost-effective, since the system will generate
bulk-profit return after 14 years of operation and reduce the FPV project risk analysis was assessed to identify factors that
system’s total expenditures until the plant project life-cycles at could affect the project’s economic life, utilizing all the parame-
25 years. The annual pre-tax and cumulative cash flows of the ters at a specific range to arrive at decisions. In this section, the
FPV project are presented in Figs. 8 and 9 respectively. RETScreen Expert software performed a Monte Carlo simulation
considering 5000 number of combinations for the risk analysis,
3.4. GHG emission analysis of FPV project using energy production cost as the key financial indicator, at a
± 25% range for the quantification of all factors. This produces a
For the GHG mitigation analysis, the GHG emission-based re-estimation of the energy production cost to produces the FPV
factor embedded in the RETScreen Expert database was used in impact risk analysis chart of the project as presented in Fig. 11.
this study’s assessment. The emissions’ analysis calculates the From Fig. 11, it can be observed from the chart that, the project
2750
M.O. Alhassan, R. Opoku, F. Uba et al. Energy Reports 10 (2023) 2740–2755

Fig. 9. Potential cumulative cash flow(s) from FPV systems project.

Table 8
GHG emissions reduction analysis.
Base Case system GHG Summary (Baseline)
Fuel type Fuel mix (%) Fuel consumption (Ktoe) GHG emission Factor tCO2 /MWh
Petroleum product 47.6 3794.0 (4409471.1 MWh)
Biomass (firewood/charcoal) 37.4 2981.3 (3464933.1 MWh) 0.638
Natural gas (electricity) 15 1199.1 (1393620.7 MWh)
Total 100% 332,155.3
Proposed Case system GHG Summary (Power proposed project)
Fuel type Fuel mix (%) Fuel consumption (MWh) GHG emission factor tCO2 /MWh
FPV solar 100% 520,233 0.007
Total 100% 23,250.9
Annual GHG emission reduction = 308,904.5 tCO2
NB: @GHG reduction credit rate of $0.70/tCO2 , GHG reduction revenue = (USD $216,233) for Ghana

electricity exported to grid and initial cost significantly impacted to the ambient air conditions (Goswami and Kumar, 2021).
the FPV project. Further deductions from the chart indicates a Evaporation rate at the Akosombo Hydro site was estimated. Fur-
direct and an inversely proportional impact of the initial cost thermore, extraterrestrial radiation statistics and radiation flow
and electricity exported to grid to the cost of energy production data for Ghana was retrieved from Anane-Fenin (1986) and
respectively. Furthermore, in Fig. 12, the project risk level is set utilized in the evaporation rate computations. Fig. 13 depicts the
at 90% confidence level (10% risk level) generated the project monthly computed fluctuation in evaporation rate. The estimated
distribution chart for risk analysis of the FPV system. Results in evaporation rate increases when air temperature rises and at low
Fig. 12, showed the cost of energy production was 136 $/MWh Hr. At the Akosombo Hydro site, the annual average evaporation
(0.136 $/kWh) becoming relatively closer to the actual project rate measures as 2.48 millimetres per day, and the maximum
cost of energy production of 100.0 $/MWh ($/kWh 0.10) attained evaporation rate estimated at 3.08 mm/day in the month of
before the risk impact assessment, confirming a low investment February. Despite the moderate-to-high temperatures and wind
risk and bankable solar floating PV project. speeds, the evaporation rate reduces significantly from May to
October, due to the considerable rainfall at these times, there
3.6. Reduced evaporation analysis will be high Hr causing the air to have reduced moisture holding
capacity then lowering the evaporation rate.
Climate factors (wind speed, relative humidity and tempera- The total surface area of the FPV system was 2,460,457 m2 . A
ture) have a significant impact on the evaporation rate of a water yearly evaporation reduction in the proposed 420 MWp FPV sys-
body (reservoir). Typically, rate of evaporation is proportional tem saves 73,327 m3 of water per year (Fig. 13). Approximately

2751
M.O. Alhassan, R. Opoku, F. Uba et al. Energy Reports 10 (2023) 2740–2755

Fig. 10. Annual GHG emission mitigation potential of the proposed FPV systems.

Fig. 11. Risk analysis impact chart on FPV project.

10 MWh of electrical energy would be generated from 73,327 m3 hydropower reservoir Dam to develop a 420 MWp FPV utility
of total annual evaporation water saved (hydroelectric) and this is system. The findings are:
due to the shielding provided by the platform on a 2,460,457 m2
i. RETScreen Expert simulations conducted at the Akosombo
dam surface. Thus, the FPV system will save 1,833,175 m3 of
hydroelectric plant facility established an FPV plant capac-
water during its lifetime (25 years).
ity factor of 14.1%.
ii. The total annual electricity that can be delivered by 420
4. Conclusion MWp floating PV system is 520,233 MWh. The projected
FPV system as a clean source of energy, will reduce CO2
In this work, a feasibility study was undertaken on an FPV- emissions by 308,904.5 tCO2/MWh each year and GHG
Hydro hybrid plant to establish the techno-economic and envi- reduction revenue of USD $216,233 at $0.70/5 tCO2 GHG
ronmental viability of integrating an FPV plant into Akosombo reduction credit rate of Ghana.
2752
M.O. Alhassan, R. Opoku, F. Uba et al. Energy Reports 10 (2023) 2740–2755

Fig. 12. FPV energy production cost distribution chart for risk analysis.

Fig. 13. Evaporation reduction and water savings potential of hybrid FPV-hydro systems.

iii. The FPV system will save water by reducing evaporation. of 12 and 15 years respectively at a project positive net
The projected 420 MWp system will save 73,327 m3 an- present value.
nually and roughly 1,833,175 m3 throughout the systems vi. From sensitivity and risk analysis performed on the finan-
working life, covering 2,460,457 m2 (2.46 km2 ) of Volta cial parameters the power system sources observed as the
Lake reservoir area. major cost impact relative to the other parameters. Net
iv. The Akosombo Dam hydroelectric plant will generate an GHG reduction posed the least impact.
extra 10 MWh per year when the hydro plant is coupled vii. The study’s finances reveal that increasing tariffs reduces
and run on the water savings from the FPV. the basic payback period, which is a crucial element of
v. For economic analysis, the normalized cost of setting up enhancing the hybrid plants’ financial sustainability. This
the FPV plant system is USD$567,030,000 according to the study suggests that a hybridized FPV-Hydropower plant is
cost analysis. At an initial capital cost of $1,350/kW and a possible in Ghana and may greatly contribute to a more
levelized electricity unit export cost rate of US$ 0.10/kWh, dependable, greener, and less expensive energy producing
an annual profit of USD $52, 238,576 generated. However, system, in meeting the 10% additional Renewable Energy
the system simple payback time and debt payment term (RE) target.

2753
M.O. Alhassan, R. Opoku, F. Uba et al. Energy Reports 10 (2023) 2740–2755

Declaration of competing interest Ghana Grid Company Limited, 2020. 2020 Electricity Supply Plan (ESP) 2020.
Ghana Grid Co. Ltd., pp. 1–58, [Online]. Available http://www.gridcogh.com/
electricitysupplyplan.
We the authors of the research work declare that we are in
Global Energy Review 2020, 2020. Global Energy Review 2020. http://dx.doi.org/
support and have no conflict of interest which had any effect on 10.1787/a60abbf2-en.
our research in any form. We therefore declare that our results Golroodbari, S.Z.M., et al., 2021. Pooling the cable: A techno-economic feasibility
are the true reflections of the outcomes as we were not faced study of integrating offshore floating photovoltaic solar technology within an
with any conflict of interest (‘Declaration of Interest: None). offshore wind park. Sol. Energy 219 (2020), 65–74. http://dx.doi.org/10.1016/
j.solener.2020.12.062.
Gonzalez Sanchez, R., Kougias, I., Moner-Girona, M., Fahl, F., Jäger-Waldau, A.,
Data availability 2021. Assessment of floating solar photovoltaics potential in existing hy-
dropower reservoirs in africa. Renew. Energy 169, 687–699. http://dx.doi.
Data will be made available on request. org/10.1016/j.renene.2021.01.041.
Google Earth, 2021. Google earth. https://earth.google.com/web/search/
akosombo+dam/@6.2994733,0.058794,35.1293386a,1599.87959474d,
Acknowledgements 35y,0h,0t,0r/data=CigiJgokCW-n8vZFMhhAEXESvu3YMhRAGZR4IAmfxug_
ITQM1VxAWPO_, (Accessed Jun. 18, 2021).
The authors acknowledge the efforts of all contributors, espe- Goswami, A., Kumar, P., 2021. Adoption of floating solar photovoltaics on waste
cially during the field work. water management system: a unique nexus of water - energy utilization,
low - cost clean energy generation and water conservation. Clean Technol.
Environ. Policy (0123456789), http://dx.doi.org/10.1007/s10098-021-02077-
References 0.
Gunfaus, M.T., Waisman, H., 2021. Assessing the adequacy of the global response
Aboagye, B., Gyamfi, S., Ofosu, E.A., Djordjevic, S., 2021a. Degradation analysis of to the Paris agreement: Toward a full appraisal of climate ambition and
installed solar photovoltaic (PV) modules under outdoor conditions in Ghana. action. Earth Syst. Gov. (xxxx), 100102. http://dx.doi.org/10.1016/j.esg.2021.
Energy Rep. 7, 6921–6931. http://dx.doi.org/10.1016/j.egyr.2021.10.046. 100102.
Aboagye, B., Gyamfi, S., Ofosu, E.A., Djordjevic, S., 2021b. Status of renewable Gyamfi, S., Modjinou, M., Djordjevic, S., 2015. Improving electricity supply
energy resources for electricity supply in Ghana. Sci. African 11, e00660. security in Ghana—The potential of renewable energy. Renew. Sustain.
http://dx.doi.org/10.1016/j.sciaf.2020.e00660. Energy Rev. 43, 1035–1045. http://dx.doi.org/10.1016/J.RSER.2014.11.102.
Ahadzie, D.K., Opoku, R., Nana, S., Ware, O., Mensah, H., 2020. Analysis of Hove, A., Qian, W., Zhao, K., Fuerst, N.K., 2020. China Energy Transition Status
occupant behaviour in the use of air-conditioners in public buildings in Report 2020, pp. 1–106, [Online]. Available: https://www.energypartnership.
developing countries: evidence from Ghana. http://dx.doi.org/10.1108/IJBPA- cn/fileadmin/user_upload/china/media_elements/publications/China_Energy_
01-2020-0001. Transition_Status_Report.pdf.
Anane-Fenin, K., 1986. Estimating solar radiation in Ghaha. Int. Cent. Theor. Huld, T., Commission, E., 2014. Mapping the cost of electricity from grid-
Physics, Trieste, Italy. 1–12. connected and off-grid PV systems in Africa. In: Prepr. 1st Africa PVSEC,
Anon, 2023. Rets. E. D. A. S. and M. T. Natural Resources Canada Natural Durban, South-Africa. vol. 2014, (September), http://dx.doi.org/10.5071/
Resources Canada, RETScreen Data Analysis Software and Modelling Tool, n.d, 1stAfricaPVSEC2014-3AO.2.4.
[Online]. Available: https://www.nrcan.gc.ca/energy/software-tools/7465. IEA, 2019. World Energy Outlook 2019. pp. 1–408, [Online]. Available:
Arjunan, K., 2019. Validity of NPV Rule and IRR Criterion for Capital Budgeting https://www.iea.org/reports/world-energy-outlook-2019%0Ahttps:
and CBA 1 Kannapiran C. Arjunan – Freelance Economic Consultant 2. SSRN, //www.iea.org/reports/world-energy-outlook-2019%0Ahttps://webstore.iea.
pp. 1–35. http://dx.doi.org/10.2139/ssrn.3505058. org/download/summary/2467?fileName=Japanese-Summary-WEO2019.pdf.
Ates, A.M., Yilmaz, O.S., Gulgen, F., 2020. Using remote sensing to calculate IRENA, 2019. Renewable capacity statistics 2019.
floating photovoltaic technical potential of a dam’s surface. Sustain. Energy Ismail, M.A., Waqas, M., Ali, A., Muzzamil, M.M., Abid, U., Zia, T., 2022. Enhanced
Technol. Assess. 41, http://dx.doi.org/10.1016/j.seta.2020.100799. index for water body delineation and area calculation using google earth
Bui Power, A., 2019. 250MWp solar project under construction. Annu. Rep. 2019, engine: a case study of the manchar lake. J. Water Clim. Chang. 13 (2),
1–92. 557–573. http://dx.doi.org/10.2166/wcc.2021.282.
Chowdhury, R., Aowal, M.A., Mostafa, S.M.G., Rahman, M.A., 2020a. Floating Kim, S.M., Oh, M., Park, H.D., 2019. Analysis and prioritization of the floating
solar photovoltaic system: An overview and their feasibility at kaptai in photovoltaic system potential for reservoirs in Korea. Appl. Sci. 9 (3), http:
rangamati. In: 2020 IEEE Int. Power Renew. Energy Conf. IPRECON 2020. //dx.doi.org/10.3390/app9030395.
http://dx.doi.org/10.1109/IPRECON49514.2020.9315200. Kougias, I., Szabó, S., Monforti-Ferrario, F., Huld, T., Bódis, K., 2016. A method-
Chowdhury, N., Hossain, C.A., Longo, M., 2020b. Feasibility and cost analysis of ology for optimization of the complementarity between small-hydropower
photovoltaic-biomass hybrid energy system in off-grid areas of Bangladesh. plants and solar PV systems. Renew. Energy 87, 1023–1030. http://dx.doi.
Sustainability 12, 1568. http://dx.doi.org/10.3390/su12041568. org/10.1016/J.RENENE.2015.09.073.
Diawuo, F.A., Scott, I.J., Baptista, P.C., Silva, C.A., 2020. Assessing the costs of Lee, N., et al., 2020. Hybrid floating solar photovoltaics-hydropower systems:
contributing to climate change targets in sub-Saharan Africa: The case of Bene fits and global assessment of technical potential. Renew. Energy 162,
the Ghanaian electricity system. Energy Sustain. Dev. 57, 32–47. 1415–1427. http://dx.doi.org/10.1016/j.renene.2020.08.080.
Drury, E., Denholm, P., Margolis, R., Drury, E., Denholm, P., Margolis, R., 2011. The Liu, L., Sun, Q., Li, H., Yin, H., Ren, X., Wennersten, R., 2019. Evaluating the
Impact of Different Economic Performance Metrics on the Perceived Value of benefits of integrating floating photovoltaic and pumped storage power
Solar Photovoltaics. NREL, Tech. Rep. NREL/TP-6A20-52197, U.S. Dep. Energy, system. Energy Convers. Manag. 194 (May), 173–185. http://dx.doi.org/10.
p. 44, no. tp://www.osti.gov/bridge, doi: Task No. SS10.2210. 1016/j.enconman.2019.04.071.
Durkovic, V., Djurisic, Z., 2017. Analysis of the potential for use of floating PV Liu, L., Wang, Q., Lin, H., Li, H., Sun, Q., 2017. Power generation efficiency
power aluminium plant in Montenegro. Energies http://dx.doi.org/10.3390/ and prospects of floating photovoltaic systems. Energy Procedia 105 (2018),
en10101505. 1136–1142. http://dx.doi.org/10.1016/j.egypro.2017.03.483.
Energy Commission of Ghana, 2020a. Energy Commission, Ghana 2020 Energy Mittal, D., Saxena, B.K., Rao, K.V.S., 2017. Potential of floating photovoltaic system
(Supply and Demand) Outlook for Ghana. 2020, (April), pp. 1–27. for energy generation and reduction of water evaporation at four different
Energy Commission of Ghana, 2020b. National energy. Natl. ENERGY Stat. 2000- lakes in Rajasthan. pp. 238–243.
2019 Strateg. 27 (9), 374–375. http://dx.doi.org/10.1088/0031-9112/27/9/ Moner-girona, M., Sanchez, R.G., Kougias, I., Moner-girona, M., Fahl, F., 2021.
008. Assessment of floating solar photovoltaics potential in existing hydropower
Eshun, M.E., Amoako-Tuffour, J., 2016. A review of the trends in Ghana’s power reservoirs in Africa. Renew. Energy 169 (January), 687–699. http://dx.doi.org/
sector. Energy. Sustain. Soc. 6 (1), 1–9. http://dx.doi.org/10.1186/s13705- 10.1016/j.renene.2021.01.041.
016-0075-y. Monforti-ferrario, F., Huld, T., Katalin, B., 2016. A methodology for optimization
Farfan, J., Breyer, C., 2018. Combining floating solar photovoltaic power plants of the complementarity between small- hydropower plants and solar PV
and hydropower reservoirs: A virtual battery of great global potential. Energy systems. Renew. Energy 87 (2016), 1023–1030. http://dx.doi.org/10.1016/j.
Procedia 155, 403–411. http://dx.doi.org/10.1016/j.egypro.2018.11.038. renene.2015.09.073.
Febrian, H.G., Supriyanto, A., Purwanto, H., 2023. Calculating the energy capacity Murat, A., Salih, O., Gulgen, F., 2020. Using remote sensing to calculate floating
and capacity factor of floating photovoltaic (FPV) power plant in the cirata photovoltaic technical potential of a dam’s surface. Sustain. Energy Technol.
reservoir using different types of solar panels Calculating the energy capacity Assess. 41 (October), 100799. http://dx.doi.org/10.1016/j.seta.2020.100799.
and capacity factor of floating photovoltaic (FPV) power plant, http://dx.doi. Oliveira-pinto, S., Stokkermans, J., 2020. Assessment of the potential of different
org/10.1088/1742-6596/2498/1/012007. floating solar technologies – overview and analysis of different case studies.
Fiabge, M., Obeng, Y.A.K., 2006. Optimum operation of hydropower system in Energy Convers. Manag. 211 (2019), 112747. http://dx.doi.org/10.1016/j.
Ghana. J. Sci. Technol. 26 (2), 9, Ghana. enconman.2020.112747.

2754
M.O. Alhassan, R. Opoku, F. Uba et al. Energy Reports 10 (2023) 2740–2755

Opoku, R., Adjei, E.A., Ahadzie, D.K., Agyarko, K.A., 2020a. Energy efficiency, Rauf, H., Gull, M.S., Arshad, N., 2020. Complementing hydroelectric power with
solar energy and cost saving opportunities in public tertiary institutions floating solar PV for daytime peak electricity demand. Renew. Energy 162,
in developing countries: The case of KNUST, Ghana. Alex. Eng. J. 59 (1), 1227–1242. http://dx.doi.org/10.1016/j.renene.2020.08.017.
417–428. http://dx.doi.org/10.1016/j.aej.2020.01.011. Sahu, A., Yadav, N., Sudhakar, K., 2016. Floating photovoltaic power plant: A
Opoku, R., Mensah-darkwa, K., Muntaka, A.S., 2018. Techno-economic analysis review. Renew. Sustain. Energy Rev. 66, 815–824. http://dx.doi.org/10.1016/
of a hybrid solar PV-grid powered air-conditioner for daytime office use in j.rser.2016.08.051.
hot humid climates – A case study in Kumasi city, Ghana. Sol. Energy 165 Semeskandeh, S., Hojjat, M., Abardeh, M.H., 2022. Techno – economic – envi-
(2017), 65–74. http://dx.doi.org/10.1016/j.solener.2018.03.013. ronmental comparison of floating photovoltaic plant with conventional solar
Opoku, R., Obeng, G.Y., Adjei, E.A., Davis, F., Akuffo, F.O., 2020b. Integrated system photovoltaic plant in northern Iran, no. April. pp. 353–361.
efficiency in reducing redundancy and promoting residential renewable Sinha, S., Chandel, S.S., 2014. Review of software tools for hybrid renewable
energy in countries without net-metering: A case study of a SHS in Ghana. energy systems. Renew. Sustain. Energy Rev. 32, 192–205. http://dx.doi.org/
Renew. Energy 155, 65–78. http://dx.doi.org/10.1016/j.renene.2020.03.099. 10.1016/J.RSER.2014.01.035.
Philip, K.A., Prosper, M., Bekoe, W., 2019. Electricity supply in Ghana: The
Sukarso, A.P., Kim, K.N., 2020. Cooling effect on the floating solar PV:
implications of climate-induced distortions in the water-energy equilibrium
Performance and economic analysis on the case of west java.
and system losses. Renew. Energy 134 (2019), 1114–1128. http://dx.doi.org/
Teixeira, L.E., Caux, J., Beluco, A., Bertoldo, I., Louzada, J.A.S., Eifler, R.C., 2015.
10.1016/j.renene.2018.09.025.
Feasibility study of a hydro PV hybrid system operating at a dam for water
Qi, L., Jiang, M., Lv, Y., Zhang, Z., Yan, J., 2021. Techno-economic assessment
supply in southern Brazil. (September), pp. 70–83.
of photovoltaic power generation mounted on cooling towers. Energy
Yashas, V.V., Aman, Bagrecha, 2022. Feasibility study of floating solar panels over
Convers. Manag. 235 (March), 113907. http://dx.doi.org/10.1016/j.enconman.
2021.113907. lakes in Bengaluru City, India. 174, pp. 1–10.
Rauf, H., Gull, M.S., Arshad, N., 2019. Integrating floating solar PV with hydro- Zhao, G., Yu, B., An, R., Wu, Y., Zhao, Z., 2020. Energy system transformations and
electric power plant: Analysis of ghazi barotha reservoir in Pakistan. Energy carbon emission mitigation for China to achieve global 2 ◦ C climate target.
Procedia 158, 816–821. http://dx.doi.org/10.1016/j.egypro.2019.01.214. 292, p. 2021.

2755