Off-Grid Appliances

Ultra-Efficiency Required
Beginner
Solar Clothes Dryer
Solar Clothes Dryer
Gas Engine Geneator
It may look easy, but operating and maintaining an engine generator is a dirty, loud, and expensive way to make energy.
Sun Frost DC Refrigerator/Freezer
Sun Frost’s DC refrigerators and freezers are highly efficient units that don’t require an inverter. High-efficiency AC models are also available.
Compact Fluorescent Bulb
High-efficiency compact fluorescent bulbs are a cheap and easy way to reduce energy loads on- or off-grid.
SunDanzer Chest-Style Fridge
The ultra-efficient SunDanzer chest-style fridges and freezers run on DC.
Bosch Dishwasher
This Bosch dishwasher saves energy by using (and thus heating) only 1.6 gallons of water per load—159% better than the DOE’s energy-efficiency standards.
Staber Horizontal-Axis Washing Machine
Staber offers efficient horizontal-axis washing machines that are top-loading.
Efficient Laptop Computer
Laptops offer all the computing power of desktop computers, while using a fraction of the energy.
Solar Hot Water Collector
PV- and engine-generated electricity are too expensive to use for heating water. Instead, use a solar collector to make hot water directly from sunshine.
Electric Chain Saw
When the batteries are full and the sun is still shining, the author uses the surplus energy for “opportunity” loads, like laundry or cutting firewood with an electric chain saw.
Solar Clothes Dryer
Gas Engine Geneator
Sun Frost DC Refrigerator/Freezer
Compact Fluorescent Bulb
SunDanzer Chest-Style Fridge
Bosch Dishwasher
Staber Horizontal-Axis Washing Machine
Efficient Laptop Computer
Solar Hot Water Collector
Electric Chain Saw

If you’re on-grid, energy efficiency is important. It saves you dollars and reduces your environmental footprint. But it’s even more important if you’re off-grid—or planning to move off-grid.

Renewable energy (RE) systems generally produce electricity that is more expensive than heavily subsidized grid electricity, with all its socialized costs and impacts. The utility grid also provides you with essentially unlimited electricity 24/7/365, without a need for storage. This makes renewable electricity seem expensive by comparison (though it really isn’t if you look at the big picture).

Why Ultra?

Off-grid RE systems must provide for all the electrical energy you want, day or night and no matter the weather. There can be several consecutive days with little sun or wind—and even when it is sunny or windy, you need a buffer between your energy sources and your energy loads. This means a battery bank, which is costly and also limited in capacity. Your backup for when energy production and the battery is low is not the utility grid, but usually a noisy, polluting, and expensive fuel-fired generator.

All of this is why, in 1984, at a time when I was not accustomed to spending thousands of dollars on anything, I bought a $2,500 refrigerator. This was shocking to my on-grid neighbors, who couldn’t imagine why I would spend so much on an appliance, when nothing else on my property had cost that much.

The explanation was clear: If I had purchased the lowest-cost fridge from the local appliance store, I would have had to spend many more thousands of dollars on additional RE gear to power the initially cheap—but lower efficiency—fridge. Energy efficiency is often the best investment you can make, if you take the long-term view.

How About DC?

My fridge is direct current (DC), a choice I might or might not make today (and would be much less likely to make for a client). Going with DC avoids the losses inherent in an inverter, which converts PV and battery DC to conventional alternating current (AC)—the electricity type most people are used to. This makes a simpler system in some ways, since the batteries are tapped directly.

When I started with RE, efficient inverters were non-existent. So my home still uses a lot of DC. The drawbacks to this strategy are that DC is not conventional, so it’s not always easy to find appliances, and some appliances—made for the RV and marine industry—are not as efficient or robust as their AC counterparts.

The other drawback is that you’ll typically end up with dual household wiring systems, because very few people can live with only DC. Most often, AC appliances are also desired, which means having two sets of wiring (DC and AC), a more expensive option. Usually the wisest choice for a modern, whole-house system is to choose all AC, buy an efficient inverter, use ultra-efficient appliances, and add a bit more energy capacity to the system to cover the inverter losses.

Phantoms Loom Larger

For large residential RE systems, small phantom loads (appliances that use energy when “off,” or for no useful purpose) are not necessarily a big deal. It’s important from an environmental point of view to reduce or eliminate them, but they are not deal-breakers when the grid or large renewable generating capacity is available.

Comments (1)

roger pangburn's picture

We've been off-grid since 1978 in San Diego area. Also paid about $2500 for a Sunfrost ( my son is still using it today with only a thermostat replaced ). Always set ac loads up with a switch to avoid phantoms. Now use a very efficient Whirlpool refrigerator. As we got more panels, started to leave the inverter on 27/7. The fly in the ointment is batteries for off-grid. I hope one or more of the new technologies will beat this problem. Payback with solar happens from the first day you get it. Forget all the calculations!

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