FMW's 25-Kilowatt Solar Panel Array

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Installing the last panel

   SolarEdge Inverters

About FMW's solar panels

In January of 2018, Friends Meeting of Washington installed a new 25.2-kilowatt solar panel array on the westward-facing roof of the Meeting Room. 

The array, consists of 84 300-Watt solar panels and two 3-phase inverters, is expected to produce about 27 Megawatt-hours of electric power per year—which will offset a portion of our overall electricity usage.

We expect to repay the $70,042 cost of installing the panels in about seven years. FMW expects to save about $3,000 per year in reduced electricity bills—at times when the panels produce more electricity than we need, we'll sell the power back to Pepco, our electricity provider. In addition, under DC rules, we will receive Solar Renewable Energy Credits (SRECs) for each Megawatt-hour of power that we generate. We expect to receive about $8,000 per year from sale of those credits, which will more than offset the cost of our electricity bills.  The array should produce about $20 a day in savings and credits in winter and $30 to $40 a day in June and July.

The inverters are connected to the Internet and report their energy production to the General Attribute Tracking System, which will generate Solar Renewable Energy Credits, which a broker will then sell for us. 

To see how the panels are doing today, just click HERE.

For even more detail, click HERE.

Here is an October 2018 update on the benefits of the solar panels to FMW.


Panel Start up

Here is an account of our panel start up in February 2018:

On February 5th, 2018, FMW Property Manager Ken Orvis flipped two switches and powered up the inverters.

Here are a couple of videos of the system waking up and starting to produce power for the first time:

In Video 1, you see Ken flip the switch to power up the first of our two inverters.

You'll see the display showing that:

— The inverter is connected to the Pepco system which is supplying 124.2 Volts AC

— The panels on the roof are sending down 11.7 volts DC

— Zero watts AC power is being produced

— 23 power optimizers, supporting 46 solar panels are communicating with this inverter.

— Status is OFF

When our Property Manager bravely flips the switch and the status changes to ON,  the inverter starts notifying the optimizers on the roof to get busy, the DC voltage climbs to about 476 volts, and then the inverter backs down into a 5-minute wake-up sequence

Ken turns the second inverter on and in Video 2, you see the wake-up countdown complete.

The display is showing 541.2 volts of DC current coming down from the roof.

You'll hear a relay click and the power output quickly climbs from zero to more than 3,000 Watts.

Then, the second inverter clicks on and also starts to generate more than 3 KW.

A little later, the two inverters together were generating more than 12,000 watts and providing a considerable part of the Meeting's power.  The Meeting House uses less than that (on average) in February, so we were probably off the grid for an hour or so and selling a bit of power to Pepco.

Another display shows that the first inverter had already generated 95-watt-hours so far today and more than 600 WH since it was installed (it produced some power during testing).