| Fire
Hall Solar-Electric System
A
datalogging system donated by Fat Spaniel Technologies gives us real-time
and cumulative data on the Guemes
Island Fire Station backup power system
performance.
"Generating
and Generated" is the total solar electricity generated.
"Used
and Using" is the electricity purchased for back-up loads
and battery charging. "Back-Up
Load" is the total electricity used by the back-up circuits
(this may include some or all of the "Generating and Generated"
and some or all of the "Used and Using").
The
Guemes community, with the support of the island energy club, equipment
suppliers, and others, raised the funds and installed a solar-electric
backup system at the Guemes Island Fire Department in the summer and fall
of 2007. It provides the fire hall with clean, local electricity, while
providing several days of backup for critical loads during utility outages.
The Fat Spaniel monitoring
system collects data on solar energy generated, back-up circuit energy
used, and grid electricity used for back-up loads and battery charging.
It does NOT measure all fire hall usage--only back-up circuits.
How
It Works
Sunshine hits the
array of forty-five 180-watt solar-electric (photovoltaic; PV) modules
on the roof, making DC electricity. These modules have a 25-year warranty
on energy production, and will likely be producing solar electricity
for the next forty-plus years. Electronic components in the fire hall
regulate the charging of the batteries, so they are full in the event
of an outage.
Inverters convert
the DC electricity to grid-synchronous AC. When the system is producing
more electricity than the fire hall is using, the surplus is sold back
to the utility, "spinning the meter backwards" and creating
a credit. When the buildings are using more than the system is producing,
electricity flows from the utility, using up the credit. The system
was designed to produce all of the fire hall's electricity annually.

Mini-System
The solar-electric
module on the wall of the fire hall is the same as the forty-five on
the roof, mounted there so you can see and touch it. It's part of a
small system that powers the lighting for this sign. It is not connected
to the utility grid.

Thanks
to: Guemes Island community members, Guemes Island
Fire Department, Solar
Energy International, OutBack
Power Systems, AEE
Solar, Uni-Rac,
Dyno Battery, Fat
Spaniel Technologies, Quality Electric Plus, Dakota
Creek, All-Phase
Electric, Home
Power magazine, and others. |