A hybrid solar and hydroelectric solution
In the past, hydro and solar power plants were developed separately, Solar Power World explains. Recently, hydro and solar power plants have begun to merge into hybrid photovoltaic-hydro plants, where floating solar panels are installed on the water surface of hydro reservoirs and/or on the surface of dams. This represents a cost-effective strategy for the allocation of new photovoltaic power plants without occupying natural lands, protecting dams from isolation and increasing hydroelectric power production by reducing evaporation losses.
How to combine solar with hydroelectricity?
In photovoltaic-hydropower plants, solar panels are integrated into the hydroelectric plant in two main ways: installation of solar panels on the downstream face of the dam, an option only possible in some plants where the slope of the dam face is less than 40° (such as in gravity dams and embankment dams), or floating solar panels on the water surface of the hydroelectric reservoir. In hybrid systems, several advantages are obtained with regard to the independent operation of solar and hydroelectric plants. In general, hydroelectric power plants are easily accessible and already connected to the grid, so installing photovoltaic panels requires less work and infrastructure.
The floating solar panel solution
Floating panels can increase the capacity factor of a hydroelectric plant by 50 to 100%, where the capacity factor of the hydroelectric plant is the ratio of the total energy produced to the maximum energy that could be produced if the hydroelectric plant were always operating at its maximum installed capacity. Floating panels can save 7 to 14% more energy than a land-based installation due to temperature reduction.
However, floating PV has one important limitation: it cannot withstand strong wind gusts, requiring a very large number of mooring points to keep it intact. The solution devised by Upsolar Floating is based on a much more robust concept where the rafts are built with polyethylene pipes and steel beams supported by 20 to 24 panels. They have been shown to withstand wind damage up to 140 km per hour.
Global energy giants join forces in floating solar power project
Recharge News reveals that some of the world’s largest utilities have joined a new group aimed at supporting a massive ramp-up of floating solar power – now widely seen as one of the most promising emerging technologies in the energy transition.
International giants such as EDF, Equinor, Statkraft and EDP are part of a joint industry partnership on floating solar power set up by technical advisory group DNV GL, which cited estimates that deploying panels on artificial inland waters alone could add four terawatts of electrical capacity worldwide.
The number of big names lining up to join the group shows the growing interest in this technology, which is increasingly present on lakes and reservoirs around the world, and has ambitions to be deployed in the oceans with “high wave” systems that can operate at sea.
DNV GL said that establishing a first recommended practice for the industry would help “investors, regulators and other stakeholders have confidence in planned projects and enforce relevant requirements,” removing a potential barrier to industry growth. DNV GL estimates that there are already 3 GW of floating solar panels in the world, mostly inland.
Toni Weigl, project manager at BayWa r.e, said “As the largest developer of floating PV systems in Europe, BayWa r.e. is pleased to be part of this consortium to develop this important guideline for the floating PV industry. We believe that establishing high and uniform standards for floating PV power plants will contribute to the maturation and improvement of the floating PV industry.”
The group hopes to have the first recommended practice ready by the first quarter of next year (Copyright).
Presentation of the actors
Energias de Portugal (EDP) is a multinational utility company. During its 40 years of existence, EDP has built a relevant presence on the world energy scene, being present in 19 countries, on 4 continents. With more than 11,700 employees, EDP is present throughout the electricity value chain and in the gas marketing business. EDP is the fourth largest wind power company in the world and nearly 66% of its energy is generated from renewable resources. EDP supplies electricity and gas to more than 11 million customers.
EDP has experience in the field of floating solar panels. In fact, EDP built the floating photovoltaic solar power plant on the Rabagão basin, in Montalegre. With 840 solar panels occupying an area of 2500 square meters, the platform has an installed capacity of approximately 220 kWp and an estimated annual production of about 300 MWh.
DNV GL is a global quality and risk management services company. Its headquarters are in Høvik, Norway. The company currently has approximately 14,500 employees and 350 offices in over 100 countries. It provides services to a number of sectors, including marine, renewable energy, oil and gas, electrification, food and beverage, and healthcare. It was formed in 2013 as a result of a merger between two leading organizations in the field – Det Norske Veritas (Norway) and Germanischer Lloyd (Germany).
Equinor ASA is a Norwegian multinational energy company based in Stavanger. It is primarily an oil and wind company, operating in 36 countries with some investments in renewable energy. As of 2017, the Norwegian government is the largest shareholder with 67% of the shares, with the remainder being public shares. It is Norway’s largest company with approximately 20,000 employees. Every day, Equinor delivers oil, gas and wind power to power the lives of more than 170 million people
Statkraft AS is a wholly owned Norwegian state-owned company. Statkraft Group is a renewable energy producer, as well as Norway’s largest energy producer and the third largest in the Nordic region. Statkraft develops and produces hydroelectricity, wind power, gas, district heating and solar power, and is also a player in the international energy markets. The company has about 3600 employees and is headquartered in Oslo, Norway.
Statkraft is heavily invested in the development of floating solar panel technology and plans to begin construction of a floating solar power plant at the Banja reservoir in southeastern Albania by the end of June