Floating Solar Power Plants
Years after the fukushima nuclear plants disaster, Japan is looking at a smart ways to double its renewable energy output by 2030.
It has embarked on building floating solar power plants on inland bodies of water-two small ones were constructed in 2015, one largest one was inaugurated toward the middle of the year , and the world’s largest is set to debut this year.
Method of Solar Power
Solar Power involves the conversion of sunlight into electricity which can be done directly using photovoltaics (PV), or indirectly using concentrated solar power (CSP). CPS used lenses or mirrors and tracking systems to focus a large area of sunlight into a small beam. PV converts light into an electric current using the photovoltaic effect.
PV is the method of converting solar energy into direct current electricity using semiconducting materials that exhibit the photovoltaic effect.
The PV effect is commonly studied in physics, photochemistry and electrochemistry and is a process that is both Physical and chemical in nature.
The first step involves the photoelectric effect from which a second electrochemical process takes place involving crystallized atoms being ionized in a series, generating electric current.
Solar PV is a clean, sustainable and proven energy technology which has been in use for fifty years. They were first mass-produced in the year 2000, when German environmentalists obtained government support for installation of 100,000 solar roofs.
After hydro and wind power, solar PV is now the third most important renewable energy source in terms of globally installed capacity with more than 100 countries using the system.
The far Niente Winery in Oakville, California pioneered the world’s first “floatovoltaics” system in the may 2008 by installing 994 photovoltaic solar panels into 130 pontoons and floating them on the winery’s Irrigation pond.
The floating system generated 477 KW of peak output and, together with an array of cells located adjacent to the pond, was able to fully offset the winery’s electricity consumption.
Floatovoltaics are an emerging form of PV systems that utilizes the surface of irrigation canals, water reservoirs, quarry lakes, and telling ponds.
Several systems are already use in France, India, Korea, United Kingdom, the United State, and Japan.
Water Vs Land
Floating solar plant offer a number of advantages that make their panels 11% more efficient than panels installed over hard ground.
In countries like Japan where cities are dense and agricultural opportunities are limited, there’s little room left over the sprawling solar plants. Water-based solar plants power and land without using any of it.
Water also helps the solar panels perform better by keeping them at a cooler temperature than they would be on land. This allows them to operate at a much higher efficiency rate, and last longer.
The body of water itself is a great benefit too. When panels are placed over reservoirs they discourage water evaporation and inhibit algae growth, which keep the reservoirs fuller and healthier.
The Japan Experience
Since 1990s solar power has been expanding in Japan.
It is the world’s fourth largest energy consumer, and solar power has been deemed of national importance since the country’s policy shift toward renewable energy after the Fukushima incident in 2011.
Leading The Way
Japan is the leading manufacturer of photovoltaics and a large installer of domestic solar PV system with most of them connected to the country’s electricity grid.
By the end of 2014, the country became the world’s third largest power producer from solar PV with a cumulative capacity of 23.3 GW, next only to Germany (38.2 GW) and China (28.2 GW).
Hyogo Prefecture Solar Station
Japan has a number of inland waterways and reservoirs built for agricultural and flood-control purposes that can be used for the development of floating Solar Power Plants.
In June 2015, kyocera corp, inaugurated the world’s biggest floating solar power station at a reservoir in Hyogo prefecture.
The 2.3 MW facility user 9,072 solar panels installed on a float made of high-density polyethylene. The station measures 333 meters in length and 77 meters in width, or around 25,000 sq. meters.
It produced 2,680 megawatt – hours of electricity per year,enough to power some 820 households.
Aside from being waterproof earthquake – proof, the solar PV panels which are UV – protected, corrosion – resistant and more durable and metallic units, are designed to withstand 118 mph winds and have a lifespan of 30 years.
The cooling effect of water on the PV panels enhances energy production capacity and makes them 11% more efficient than land-based systems of similar size.
Chiba floating solar power plant
The floating solar power plant at chiba prefecture near Tokyo, set to open March this year, will dwarf that of Hyogo prefecture and will be the biggest of its type by then.
The 13.4 MW facility, also built by kyocera, will have 50,000 solar panels installed over a water surface area of 180,000 sq. meters.
It will produce approximately 15,635 megawatt – hours of electricity a year, enough for almost 5,000 households.