SolarEdge Floating PV System Filters Smart Energy into Savings for Wastewater Plant
The Challenge
Rising Electricity Rates and Limited Space for Solar
California electric utilities have been raising rates 3-5% every year. Increased frequency of wildfires in Northern California will have an even greater impact on rising rates. Leadership for the Lake County Special Districts knew the solution to controlling wastewater treatment plant costs was turning to cheaper, renewable sources of electricity. However, they were concerned that the property did not have adequate land or rooftop space to install a PV system large enough to offset consumption.
The Solution
Turning to Water for Solar
After issuing an RFP and reviewing the bids, Lake County Special Districts concluded that the unused wastewater treatment pond provided an incredible opportunity, and a large enough footprint, to install a floating solar system. North Coast Solar, a pioneering solar firm in Santa Rosa since 1984, won the project with a proposal to install a solution from Ciel Et Terre – well-known developers of the Hydrelio floating solar power system.
This included a 252 kW design, using Canadian Solar modules and SolarEdge power optimizers/inverters. The solution would cover the plant’s annual kWh usage, and projected annual electricity savings of $90,000, which would grow over time as PG&E rates increase and monthly lease payments stay constant. And, with the innovative municipal lease financing arranged by North Coast Solar, only minimal upfront investment was required, allowing them to generate positive cash flow in the first year of operation.
Brian Hines
Floating Solar Makes Sense
More Energy. Less Environmental Impact.
Floating solar power plants improve energy production by keeping the solar system cooler, which prolongs the lifetime of the PV system and improves performance. This cooling factor is an even bigger benefit in Lake County where summer temperatures can reach 106° F. Utilizing the pond surface for a solar plant also reduces algae growth, bank erosion (through reducing water movement), and evaporation, while generating virtually free energy. Benefits also include reduced greenhouse gas emissions, offsetting 131 tons of CO2 per year - enabling the County to meet specific carbon reduction goals.
SolarEdge – By Land and Water
Maximum Power. Maximum Safety.
With modules on water, on-site monitoring, maintenance, and the safety of personnel are potentially more challenging. Through module-level monitoring, SolarEdge power optimizers help reduce maintenance visits and costs through remote problem-solving and upgrades. SolarEdge meets safety regulations by complying with NEC requirements for Arc Fault Protection (AFCI) and Photovoltaic Rapid Shutdown System (PVRSS). SolarEdge power optimizers are also designed to meet IP68 and NEMA6P rating for water and humidity resistance.
Module mismatch is almost always unavoidable, especially with floating (moving) installs. SolarEdge’s maximum power point tracking ensures each module produces at its maximum power. SolarEdge technology also allows up to 40% less DC cabling compared to string inverter solutions - cutting down on the amount of material needed in a typical floating PV installation with long rows of solar modules in landscape orientation. In addition, long power optimizer input cables support the landscape orientation that is standard for floating PV installations.
Environmental Savings:
This PV system produces energy equivalent to:
