Homewood Goes Solar

The first photovoltaic power was generated in Homewood on November
19, 2011, at 8:30AM.

A demonstration system installed by local ‘green’ connoisseur, Barry Latham, went live and began generating a very tiny amount of power amidst the thick cloud cover Saturday. Although the system itself will only generate approximately 1 kilowatt of power at its peak performance, this is still a big step for Mr. Latham and for Homewood. The modules used (also known as 'solar panels’) are between 165W and 175W each and were supplied by BP Solar. The M190 invertors, which convert the direct current (DC) electricity to alternating current (AC) electricity, were provided by Walker Solar. The aluminum roof-mounted system, also provided by Walker Solar, is a UniRac system. For a very clever instructional video, see the attached link here. With simple instructions included with the invertors, it was a breeze to get the system up and running in no time. Once all of the parts were acquired, it only took a long weekend to go from ComEd supplying all of the residential power, to ComEd being supplemented by the Sun.

With any emerging technology, there are upsides and downsides.
One major upside is that the electric bill is smaller each month, especially in
the winter when the central air conditioner doesn’t run. Another upside is that
the system detects the voltage (240V AC) and frequency (60Hz) of the power
coming from the local utility and matches it with the power that it provides.
If the voltage spikes, a safety feature blocks the transmission of power to
protect itself from overloading. If the voltage drops, the system interprets
this as a power failure and turns off, protecting any linemen from getting
electrocuted when dealing with downed wires that shouldn’t be carrying any load!
Thus far, the only downside is part of one of the safety features: should the
power fail, then the residence isn’t creating an ‘island effect;’
if the neighborhood loses power, so does the Latham residence.

The Enphase invertors are also part of a revolution in DC to
AC conversion. In the past, all of the modules had to be wired together then
run through a central invertor. The major drawback of this is that the maximum
wattage of the system was dictated by the lowest-wattage module, and that
included a broken module (0W) or one temporarily shaded by a tree or cloud
(0W). With individual invertors mounted to the back of each module, each module
acts independently and the current is added in series, rather than the voltage
in parallel.

One of Enhase’s greatest assets is their community of Enphase
users that connect through an Enlighten router to the
internet. The newly added Latham residence can be viewed live here.
Because of the location of trees and the roof line, the system isn’t visible
from the street, unfortunately.