Near the shore of Lake Ontario, Rochester's Emerson Street Landfill is now the home of a two-megawatt solar farm, which will help the city save $80,000 per year on electricity costs. Even better, Rochester doesn't have to invest any money up front. AES Distributed Energy will finance, operate, maintain, and own the facility, working with Solar Liberty, a private company in Buffalo NY, as its subcontractor. The municipality signed a 25-year power purchase agreement (PPA) with AES Distributed Energy, saving the city around $2M in electricity costs over the life of the contract.
Trash into Treasure
In addition to being built on a landfill, the site's pad consists of a layer of soil mixed with slag that had been dumped into Lake Ontario back in Rochester's steel industry days. (The slag material was excavated during another municipal building project.) This saves the city from paying $4M in slag removal and disposal fees and puts the waste to better use. Why put the slag into a landfill when it makes a great landfill covering material?
Rather than penetrating the ground surface, the array is ballasted with concrete blocks holding the racks in place. The array conforms to ASCE 7-05 standards for wind load.
Electrical Specs
Nearly 8000 photovoltaic panels will deliver up to 2.6 megawatts of DC power to 73 grid-tied string inverters. With a 98% inverter efficiency rating, the solar farm can put over 2.5MW (AC) onto the electric grid. The inverters can provide reactive power with a power factor anywhere between 80% leading to 80% lagging, allowing the array to handle VAR compensation.
The ground-mounted array faces due south, with panels tilted at an angle of 15o to maximize summer energy production, decrease inter-row shading, and fit the most panels into the allotted space. To lower the construction cost and reduce maintenance, the panels will not track the sun.
Reduced Carbon Footprint
Every year, the renewable energy from Rochester's PV farm will prevent 2300 metric tons of greenhouse gasses from entering the atmosphere. That's equivalent to the annual CO2 emissions from more than 500 gasoline-powered cars. The solar field is part of the city's climate action plan, which aims to reduce CO2 emissions by 30% over the next 20 years.
Here's Mayor Warren's press conference at the groundbreaking ceremony:
The project broke ground in May and is expected to be online sometime this fall.
Images and video courtesy of the City of Rochester NY
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