Floating photovoltaic solar energy is gaining relevance around the world. Recently, plants with a capacity of tens and even hundreds of megawatts were installed in China, with more planned in India and Southeast Asia. In 2018, the accumulated installed capacity of floating solar panels was 1,000 MW, of which more than 500 MW were installed in the same year. At the end of 2020, the cumulative installed capacity of floating solar photovoltaic (FPV) was estimated at more than 2,500 MW globally.
FPV systems have certain advantages and benefits over ground systems. One of the main advantages is that these projects do not compete with other land uses, a relevant aspect especially for islands and other countries where the availability of land for power generation is scarce. The World Bank estimates that just by using 5% of the available surface in water reservoirs in Latin America it would be possible to install more than 180 GW of floating solar energy, a value equivalent to the total installed capacity of electricity generation through hydroelectric plants in the region. In addition, these systems can bring other benefits to reservoirs, such as reduced evaporation and eutrophication of the water body.
Likewise, FPVs can have a higher energy efficiency than traditional solar projects, since the water helps to cool the solar panel – minimizing thermal losses – and it receives more solar radiation thanks to the reflection of the water. Additionally, shadow-related losses will likely be less than those from terrestrial solar plants.
How Floating Solar Power Can Supplement Hydro Power Plants
Of particular interest is the possibility of adding electricity generation capacity with floating solar energy to existing hydroelectric plants, since FPVs can complement the hydroelectric resource, offset the electricity production of hydroelectric plants during dry seasons and reduce evaporation of water in the reservoir. This will make it possible to increase hydroelectric generation. In addition, the hydroelectric plant can be operated flexibly to adjust its generation to the short-term variability of solar energy.
The capital costs of floating solar systems are even slightly higher (or comparable) to photovoltaic projects built on land. However, they are expected to decline over time, due to greater economies of scale. Total capital costs for floating PV installations in 2018 generally ranged from USD 0.8 to 1.2 per Wp, depending on the project location, the depth of the water body, variations in that depth, and the size of the system.
Considering all the advantages described above and the high contribution of hydroelectricity in Latin America, which in 2019 supplied around 45% of the electricity demand, it is estimated that these systems are consolidated as an emerging technology with enormous potential for the region. However, it is still a technology at a very early stage of development in the region, and only a few pilots have been implemented or planned, for example in Panama, Colombia or Brazil.
IDB supports the development of FPV in Suriname
The Inter-American Development Bank (IDB) is currently supporting the development of FPV in Suriname with a Technical Cooperation financed by the Special Funds of Japan to study the feasibility of integrating these systems in the Afobaka hydroelectric plant. This plant currently generates around 50% of the total electricity consumed in the country. The electricity supply in Suriname is critical during the peak periods of the dry season, coinciding with the warmest and sunniest periods of the year, where also the consumption of air conditioning in buildings tends to be higher.
This project will help supply electricity during these peaks and optimize the management of water resources to have reserves at critical times. The FPV system can be connected to the same transmission line from the hydroelectric plant, managing solar and hydroelectric generation in an integrated and optimal way for the network. The Technical Cooperation will also analyze the value chain for the supply, installation, operation and maintenance (O&M) of the project and will propose recommendations to increase local content and create new local green jobs.
There are still many open questions regarding the proper implementation of the technology: what additional feasibility studies need to be conducted to protect the local environment? What are the differences in operation and maintenance practices compared to traditional photovoltaic plants built on land and do they have a higher cost? How should bidding processes and procurement contracts be adapted to the new technology?
In order to answer these and many more questions and close the existing knowledge gap, the IDB has partnered with the Clinton Foundation’s Climate Initiative (CCI) to launch a virtual training in FPV focused on Latin America and the Caribbean. The courses include a module on hybrid systems, including hybrid FPV-hydroelectric systems, a section on procurement processes and are especially aimed at decision makers and technical personnel in hydroelectric power companies and public sector organizations interested in the development of the technology.
If countries are truly interested in accelerating the decarbonization agenda, we must consider all technically and economically viable options, and FPVs have the potential in our region to make a concrete contribution to that common goal. Other technologies such as wind power have made the leap into the waters with great success in many countries. Now it is FPV’s turn to start generating sustainable and affordable electricity for all.