Backup Power Options for Your Cabin

Given the prolonged power outages due to the Bighorn Fire, the ensuing loss of stored food and the fundraising efforts to replace the Fire Station’s aging generator, this seems like the ideal time to evaluate backup power options for individual cabins.  I am responsible for the care and feeding of four permanently-installed generators on the mountain and two in Tucson, as well as a small fleet of portable units.  This article includes some of the knowledge gained from this experience.  Multi-day power outages after winter storms are not uncommon on the mountain, so those of us that enjoy winter use of our cabins should pay special attention to this information.

First, I would like to dismiss a recent marketing ploy by a number of battery bank manufacturers selling “solar generators.”  These devices claim to provide a more environmentally-friendly and silent replacement for mechanical generators.  In reality, these are simply battery packs with solar panels attached.  While they are appropriate for running a few devices while camping, they are not suitable for keeping your food cold for days at a time.  Unfortunately, the current state of battery technology has not achieved the energy density and affordability of combustion-based generators.  For the foreseeable future, multi-day runtimes and whole-home capacities are out of reach for most homeowners.

The most economical generator option is to use a portable unit connected to critical devices.  These should be connected to a professionally-installed generator inlet/manual transfer switch such as the Reliance Controls Corporation 31406CRK.  This eliminates the need to string extension cords all over the cabin, provides a means to connect hard-wired appliances to a portable generator and allows a weather-tight connection for the cable entering the cabin.  A sufficiently long cord should be used from the inlet to the generator to keep noise and exhaust fumes as far from the cabin as possible.  The primary downside to this option is that the generator has to be manually connected, powered up, refueled and put away whenever the power goes out.  This solution only helps when someone is at the cabin to deploy it.

Portable generators are available in propane, gasoline, propane/gasoline dual fuel and diesel versions.  Gasoline and diesel require a fuel stabilizer additive when stored for long periods.  Stabilized gasoline should be replaced every year while stabilized diesel should be replaced every two years.  Diesel also requires an anti-gelling additive if used in the winter.

The most robust option is a permanently-installed automatic transfer switch and generator.  These are available from Kohler, Generac, Briggs and Stratton among others.  Models are available for use with propane (usually convertible to/from natural gas) and diesel.  My preference for cabin-sized installations is propane since it can be delivered and has a long shelf life.  A larger propane tank and regulator may be required If your cabin already uses propane.  This will provide an adequate run time and fuel flow for the new generator.  Many permanently-installed generators have a remote telemetry option available so that you are notified (usually via an app on your phone) when the generator is running, when utility power is restored and if the generator requires maintenance.

Transfer switch/generator combinations are available in partial and whole cabin versions.  A partial-load transfer switch is installed “after” the existing circuit breaker panel.  Critical circuits are disconnected from the existing panel and are moved to the transfer switch.  The cabin owner decides which circuits are critical based on their needs.  Commonly backed-up circuits (depending on location) include refrigerators, medical equipment, sump pumps, well pumps and heat tape used to keep pipes from freezing.  Once the list has been compiled, an appropriately-sized transfer switch and generator can be selected.

A whole-home transfer switch is installed between the Trico connection and the existing circuit breaker box.  All devices are switched over to the generator when a loss of utility power is detected.  The tradeoff to this convenience is cost – both in the initial cost of the generator and in fuel consumption when the power is off.

Any mechanical generator will require some maintenance.  Most manufacturers recommend annual replacement of the engine oil, oil filter and air filter.  Replacement is also recommended after prolonged use – the definition of prolonged varies by manufacturer and model.

Many generators have cold-weather kits available, which are required for winter conditions on the mountain.  These use electric heat elements to keep the battery from freezing, keep the oil viscous enough to circulate and prevent formation of ice on the carburetor.  Some generators also require a high-altitude kit for use at our elevation.

Transfer switches of any kind should be installed by a licensed electrician.  Any permanent fuel lines should be installed by a licensed plumber or your propane vendor.  Oil and filter changes can be performed by cabin owners or any small engine repair technician, but work on the electrical side of the generator should be performed by a generator technician.

When utility power is lost, generators take anywhere from a few seconds to a few minutes to come online and take over your cabin’s power load.  A small uninterruptable power supply between your critical electronics (router, cell phone booster, etc.) and the wall outlet will bridge this gap, preventing dropped connections while the generator spins up.

Generator manufacturers’ websites are a good place to start finding the ideal fit for your cabin and budget.  Generac has an online tool ( which will help you select a generator size based on which appliances you wish to power.  Once you know which size you need, you can compare prices and features between brands.

Author: matthew