Backup Power - Batteries vs. Generators

Backup power systems have become a mainstay of off-the-grid homes for decades. Historically, most of the homeowners using these systems tended to be located in rural areas, where access to utilities like electricity, water, gas, and cable, might be limited or non-existent. However, as we’ve seen over the past few years, solar, backup batteries, and generators are also gaining traction in on-grid markets as a method of ensuring redundancy when the grid goes down.

Why so many homeowners are considering backup power systems.

There are several reasons we’re seeing a tremendous increase in backup power systems. Wildfires and freak winter events can cut off your power for days or even weeks at a time- as we regularly see in California or Colorado during the seemingly longer every year fire season or during the winter months in Texas.

In a more mundane development, people are using ever-increasing amounts of power in their homes, increasing load demand to record highs. Backup power systems also offer up a great deal of utility to homeowners who are looking to save money, either via solar panels reducing sky-high power and energy bills or by replacing their gas vehicles with electric vehicles that often work in tandem with backup batteries.

Overview and Comparison of Batteries, and Gas Generators

Let’s take a look at batteries, and gas generators- how they work, their reliability, costs, and internal space requirements.

Backup Batteries: How They Work

Battery backups offer up an eco-friendly, safer version of a traditional gas generator. They’re used for several different applications, including as a backup for when the power goes out as well as a way to store power for later use. For instance, you may charge your in-home battery pack during daylight hours and use that energy later at night to charge your electric vehicle or reduce how much energy you use during peak times.

How Reliable are Backup Batteries
This really depends on your expected usage, features, and capabilities, and the manufacturer of the battery pack itself. The first thing that you should know is that in the event of a power outage, your backup battery system might not be able to run your home at normal capacity. That means you won’t be able to run 3 TVs, the air conditioner, and all of the house lights. Of course, with the right capacity, you can, but for most residential systems you’ll want to watch your power usage.
Backup Battery Costs
Most backup battery systems will cost anywhere from $2,500 (Orison) to $5,500 (Tesla Powerwall 2) to $8,000+ (Flex Energy Storage System). You can also upgrade these systems or install multiple systems in a home to match a larger demand for backup power. You can find a current list of 2022’s best backup battery systems here. Keep in mind that these are just prices for the actual units, installation can range from anywhere between $1,000 and $2,000, depending on where you live.
Backup Battery Space Requirements
A battery bank that would suffice for the power usage of an average American household needs to supply around 90-kilowatt hours of energy. However, 13.5 kilowatt-hours is typically what you’ll get out of a single unit, such as the Tesla Powerpack 2. So you’ll either need to reduce usage significantly, use it for niche cases, or if necessary, add extra battery packs where possible.
Most families put power packs in out-of-the-way areas, both for safety and aesthetic reasons. We can help you find the perfect spot in your Custom Home Plan. The Powerpack 2 has dimensions of 45.3 in x 29.6 in x 5.75 in, weighs about 250 lbs, and can be mounted on the floor or a wall. Sizes between manufacturers will differ but you can get a rough estimate by looking at the Tesla Powerpack 2 datasheet, here.

Generators: How They Work

There are several different types of generators you can use to power your home in an emergency, including those fueled by gasoline, diesel, natural gas, or propane. However, for the average custom or luxury home, you’re probably looking at natural gas or liquid propane for safety and efficiency reasons.

How Reliable are Generators
Traditional fuel generators are a tried-and-true technology, used by everyone from residential households to major corporations to the United States Military. You can run them at night as long as you have proper fuel supplies. With regular maintenance and prop safety procedures generators are incredibly reliable and can fill in the gaps left by newer tech like power packs and backup batteries.
Home Generator Costs
Generators come in a wide array of shapes, sizes, and capabilities. On the low end, you can find a small gas-powered generator for a few hundred dollars- good for basics like charging your phone or laptop. Home-scale systems tend to be pricier, with whole-home generators running anywhere from $2,000 to $25,000+, again dependent on size and capability. Installation for a home generator will also cost you somewhere between $1,000 and $10,000. You’ll also have to worry about ongoing fuel costs. As many generators run on fossil fuels, you can get a feel for how much it will cost to run your generator by paying attention to fuel prices.
Generator Space Requirements
Unlike battery packs, generators typically need to be located outside. Most manufacturers recommend that your generator should sit outside of your home, at least five feet from vents, windows, doors, and flammable materials. The actual footprint of your generator depends on its capabilities, fuel source, and several other factors- you can look up specs for some common models here.
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