By Donna Nicol
Life in Vermont is a unique experience, especially for those who choose to live somewhere off the beaten path. In the past few years, the off-grid solar system and resulting lifestyle has been eclipsed by its more glamorous, but necessary sibling, the net-metered, grid-tied PV system. It’s wonderful that so many people are going solar and choosing to make electricity for their homes and their communities. But let’s shine a spotlight on the modern off-grid PV system.
First, what is an off-grid PV system? It is a photovoltaic system that is a complete, on-site power plant for your house, cabin, or camp where electric companies haven’t installed power lines. Off-grid systems vary widely in size and cost depending on the loads the owner desires or requires to run (in other words, the things that use electricity) and the unique qualities of the site. The major components of a system are the solar array, the inverter, a charge controller, and the battery bank. These individual parts will determine how much power is generated, how much power is available in the conversion to household current, and how much power is held in reserve. And although there is a greater awareness of energy efficiency now, it is most vital when designing an off-grid system. The size of the system (and therefore its cost) is determined by the appliances the homeowner intends to power. Water pumping and refrigeration are necessities, and these appliances and their electrical consumption are considered first when building a system. Next are appliances where use is more driven by choice – if an appliance generates heat (typical examples include a toaster, coffee maker, or dishwasher), it needs careful consideration because these items use a significant amount of power and will increase the size of a system. Off-grid systems are capable of providing every comfort and convenience of a “standard” home. They usually accomplish this by considering high levels of efficiency rather than making extraordinary investments in power production. We design systems that work as efficiently as possible.
OK, you say, so what is the cost? Budget, of course, is perhaps the largest consideration in choosing the size of an off-grid power system. The smallest systems provide DC current only. These systems are great for camps and cabins, providing power for simple living with lighting, DC water pumping, and even entertainment systems. These solar systems range in price from around $3,500 to $5,000. Adding more solar modules increases your charging capacity. Include an inverter, and now you have AC current available such as that in a standard house. Many inverters also include battery chargers that work with a generator to back up the solar array as your source of charging for your battery bank (think dark months, November and December). Battery bank size is determined by the amount of reserve power required but also by the amount of charging capacity available. We do not oversize battery banks relative to the amount of charging available. Mounting for the solar modules is another consideration that has impacts on the cost of the installed system. In short, these larger systems which provide many or all of the conveniences of a standard, grid-tied home range in price from $15,000 to $25,000. Systems can be much larger, thereby capable of producing and storing significantly more power.
The sky’s the limit and the equation is simple: more watts = more dollars! In short, the off-grid system is tailored to the needs of the homeowner. It’s a viable option for producing your own power and living off the beaten path! [Editor’s note: … or even on the beaten path. It is a viable option for nearly anyone.]
Solartech’s owners, Rich and Donna Nicol, have been living and evolving an off-grid lifestyle for nearly twenty years now in Sutton, VT. They design, install, and service off-grid and grid-tie systems. For more information, call 802-467-3500, email firstname.lastname@example.org, and visit www.solartechvt.com.
This is the first in a series, Living with Solar, Off the Grid and On — in the Northeast, that will be featured in Green Energy Times.