d
i
r
G
he
t
f
f
O
g
n
i
v
Li
right
f
ing o
Is liv
the
f grid
?
r you
e fo
choic
ld
e
f Greenfi
By Geof
When considering a renewable energy system
either on grid or off grid, it
is important to explore what your root motiva
tions are, and to involve your
entire household in the decision.
It seems appropriate as I begin writing this essay that I am
waiting for the propane guy to hook up the gas pipe to our
home’s new back up generator. While it may seem strange
that I begin an article about renewable energy by mentioning fossil fuel generators, it makes perfect sense when you
consider that the purpose of this article is to describe what
living “off grid” entails. Off grid simply refers to a house that
is not connected to the utility distribution grid. Thinking
back on my own planning and preparation for my solar and
wind powered home, I think that most of the articles I read
and folks I spoke with were quick to emphasize the “good
stuff” without delving into some of the sometimes difficult
realities of depending on and taking care of an independent
power system. I hope to share my experience with those now
considering this renewable energy option, so that they can
make a fully informed choice.
I chose to live off grid for a variety of reasons. While my primary motivation was environmental, I also had a strong attraction to the technological aspects of renewable energy (the cool
electronic equipment) as well as an aspiration to live independently. It is important for anyone considering off grid living to
explore what their root motivations are. The decision should
include everyone in your family; it is much better to figure out
ahead of time whether or not your spouse and kids are as ready
for this lifestyle change as you are! I often meet people who
initially want an off grid system, but end up choosing a grid
tied renewable energy system after they assess their motivation, the realities of an off grid lifestyle and the costs and
performance of the various options available today.
Many of us have spent years reading and dreaming about going solar, and for most of that time we may have been focusing on “classic” stand alone, independent systems dependent
on battery banks. For many, this image has become an engrained part of their renewable energy dream, and the inertia
of this vision keeps them from discovering that they might be
better served with one of the new “on grid” system options.
With such a system, more of the budget can go toward the
productive part of the project (the PV or wind) instead of
paying for batteries, electronics and complicated installations
(not to mention that fossil fuel generator!) A grid tied system
can be the ultimate in simplicity, with no user involvement or
maintenance, other than checking the system monitor to see
how much energy you produced recently.
The realities of living with an off grid system are far less
simple. Before I begin describing them, let me clarify my
position – I live off the grid and enjoy it (most of the time).
It is the right choice for many people, and my company contin-
The Greenfield home near Athe
ns, Ohio features both wind and
solar energ y systems and functions
totally independent of utilit y lines
.
ues to design and install them, from small remote cabin systems
that run a few lights to fully automated power plants large
enough to run central air conditioning and lights galore. When
we built our home, utility tied systems were just taking off in
California and were not an option yet in Ohio. Our land did not
have utility power and a line extension would have cost about
half of our initial system expense. On top of that, I was strongly
motivated at the time by a desire for “independence,” which has
waned over the years though, and today I would say I am more
focused on “inter-dependence.” If I were to consider my options
today, I would probably choose to go grid tied (unless you asked
me during a power outage in which case my answer would be
off grid – or possibly grid-tied with battery back up!)
So what are these realities of off grid living that I had mentioned?
Well, as opposed to being connected to a power plant, with
your energy usage limited only by your wire size and your
ability to pay the monthly utility bill, a renewable energy
system usually has limits. With enough of a budget the sky is
the limit, but for most people the system will only be able to
deliver so much power. Depending on the size of the system,
this may mean no central air, deep freezer, arc welder, kiln,
toaster or hair dryer! Every system has two limits: the first is
the amount of power you can draw at any instant, usually
determined by inverter size (in watts), and the size of the battery bank. Many of us become adept at monitoring our use and
avoiding concurrent power hungry activities. The last time we
bumped into our “power ceiling” was running the dishwasher
at the same time as doing laundry: three motors started at once
and the lights went out! Luckily it was only an inconvenience,
and simply had to press the reset button on the inverter (and
plan better next time). The second limit affects the amount of
power you can draw over time. We often describe this part of
off grid living as “living within your means.” If your solar array
generates 10 kilowatt hours (kWh) of power from the sun and
you use 15 kWh, you are not living within your “solar” means.
A battery bank can act as a temporary source of “credit,” but
keep it up and your battery bank will be tapped out (and seriously degraded).
Your only solutions to these limits are to use less power (offgridders quickly become efficiency experts), expand your solar
array or fire up the generator. I am talking about generators
again; for most off grid systems, a strong and reliable fossil fuel
(or bio-fuel) generator is a required component. Even with the
largest solar array there will be periods after an overcast day
that the generator must come to the rescue. If batteries are left
at low voltage for too long, or fail to be fully charged on a regular basis, they will fail prematurely requiring a costly replacement. While a hybrid wind and solar system can reduce the
amount of generator run time, it is still a regular winter time
occurrence as our region, in southeast Ohio, averages about
two “solar hours” per day in the winter, as opposed to more
page 43
continued on
www.GreenEnergyOhio.org
31