The Orlando Utilities Commission (OUC) recently started experimenting with a new way to weave sustainability into its clean energy portfolio, installing a floating solar array on a large pond next to its Gardenia Operations Center. The $90,000 project, which will pay for itself in energy production over time, was put together by a team of OUC renewable energy experts.
The OUC project is one of only a few floating solar installations tied directly into the U.S. electric grid. OUC owns and operates the pilot 31.5-kW floating solar PV facility, which is directly connected to the OUC grid.
“We’re using an area that is already devoid of trees, and the reflectivity of the water will actually increase the capacity of the 100 solar panels,” said OUC Vice President of Emerging Technologies Byron Knibbs, noting the impetus of the project was from trying to help new developers add solar to properties, which often include ponds or small lakes. The array will provide enough energy to power about five homes.
The Smart Electric Power Alliance (SEPA) weighed in with a buoyant but engineering-savvy assessment: "SEPA applauds the creative problem solving OUC has undertaken with their floating solar array," said Jennifer Szaro, senior director of programs at SEPA. "As with any novel approach to investments in these types of design solutions, a pilot program like this will reveal the viability of floating arrays on a grander scale and allow for more effective future iterations."
OUC was the first utility in Central Florida to build a large solar farm and was one of the first in the nation to offer community solar where its customers can “buy a piece” of an array.
If pilots like this one proceed successfully, it appears that floating solar PV arrays will likely make sense for many areas in the United States, and could become a significant additional element in our electric grid’s range of generation sources, when you consider the following facts:
Fact 1: A federal law in the United States requires that reservoirs be covered. (See EPA–HQ–OW–2002–0039; FRL–8013–1: National Primary Drinking Water Regulations: Long Term 2 Enhanced Surface Water Treatment Rule)
Fact 2: There is a strong overlap between areas that historically experience drought and areas with high penetration levels and strong markets for solar power.
Fact 3: Covering reservoirs, even partially, provides significant economic benefits. Consider how, famously, the largest municipal utility in the United States, Los Angeles Department of Water & Power (LADWP), had installed millions of floating black plastic balls over many of its reservoirs to reduce evaporation during California’s drought, at the expense of hundreds of millions of dollars. Two side benefits reported for the initiative included the temperature reduction in the reservoirs, which reduced chlorination costs due to lower levels of algae growth, and reduction in levels of carcinogenic chemicals being synthesized in the water (such chemical reactions occur in the presence of higher temperatures and higher incidence of sunlight).
Fact 4: According to a study by the Association for the Sciences of Limnology and Oceanography, excluding the Great Lakes, there are 131,000 sq km of surface area on the 3.5 million lakes and reservoirs in the U.S., sized greater than 1000 sq m. If we take the 131,000 sq km figure from that study and set a goal of achieving installation of floating PV arrays on 1% of that surface area, it would more than triple the total U.S. installed base of PV capacity.
Fact 5: Developers or property owners interested in including solar PV arrays in their plans may not have the desired unobstructed roof space or unobstructed land for the arrays, but may have space atop retention ponds or other bodies of water where PV arrays could be ideally situated.
The fixed solar panels used by OUC are manufactured by Ciel & Terre and were installed directly atop floats, in a sequential fashion at the lake’s shoreline. The installation process, which was completed easily over a period of two days, is recorded in a 14-second-long series of time-lapse photographs, currently available on YouTube at this link.
As of May 2017, a review of the Ciel & Terre website shows total installation of 5 MWp of its floating solar systems in 2014 and 30 MWp in 2015, including facilities ranging from 1 MWp to 7.75 MWp in Singapore and Japan, at this link.
The full OUC press release is available at this link.