A Guide to Whole Home Battery Backup

What Is a Whole Home Battery Backup?

How Does a Home Battery Backup Work?

Benefits of a Home Battery Backup vs Generators

The ongoing wildfires devastating California and parts of the northwest and the tumultuous hurricane season now underway in the southeast, will likely mark 2020 as a year of reckoning in the fight against climate change. Although you may not live in a natural disaster hotspot, you likely have experienced a power outage; a storm or driver hits a neighborhood utility pole and just like that, lights out!

Like most of us, while searching for candles and flashlights, you think momentarily about your home's energy resilience. The pandemic, however, is a change maker on that front. With 64% of salaried US employees working from home, the need for reliable residential power is greater than ever.

It seems obvious, but the best time to think about emergency backup power is before the grid goes down again. Climate-minded homeowners will want to consider bolstering energy resilience with an energy storage system, or rechargeable home battery vs. a generator that is powered by fossil fuels.

Beyond the type of fuel (clean vs. dirty), the question becomes whole home battery backup or partial home backup and which delivers optimal performance for your budget and lifestyle.

What Is a Whole Home Battery Backup?

Whole home battery backup means having access to all of your home's circuits so that you can decide which appliances to power in a grid outage. Those decisions can be based on many factors including; lifestyle needs, time of year, solar production, battery size, and battery charge state.

Sounds simple, but energy transmission is a complex process and is highly regulated for safety. When power enters a home via the main electrical panel, it passes through circuits which manage the current flowing to our appliances, phones, computers, and anything else we use that consumes energy. Introducing a battery into the mix, that is capable of picking up where the grid leaves off so that everything from your freezer to your Wi-Fi continues to run smoothly, is no small feat.

In this whiteboard video, we illustrate a couple of backup scenarios for the average home which consumes about 30kWh per day. When actually quantifying how much power you really need during an outage, it becomes clear for most homeowners that whole home battery backup may not be necessary. An alternative strategy, made possible by Lumin's technology that allows for flexible energy management, is to configure a system with partial backup. In this scenario, homeowners have more choice when it comes to making backup decisions. Battery backup for home appliances, for example, is a good place to begin an audit of your energy needs.

Right-sizing your battery-figuring out the size of the battery needed to deliver the amount of power you require - is a critical next step. This metric will greatly impact the cost of your emergency battery backup power in addition to the type of battery you wind up buying.

If you've done any research on the different batteries available today, you'll discover they differ due to their chemistry. To mention a few, lithium-ion, lithium iron phosphate, lead acid, and even salt water batteries are among the popular choices today and each have their pros and cons.

How Does a Home Battery Backup Work?

Home batteries are installed only by qualified electricians and connect directly into a home's electrical distribution system. The battery charges by drawing power from the grid, or more commonly, a solar PV system and storing it for use during an outage or when a solar PV system begins to shut down for the night.

When a battery is programed for emergency backup and the grid goes down, the battery can power a home for about 24 hours, depending on its size and how much stored energy is being used during the outage.

In an extended outage however, the battery will ultimately be fully depleted and that is why most home batteries are paired with solar. The combination of solar + energy storage is a powerful energy resilience strategy because when the grid is down, the battery can continuously recharge, drawing power from solar.

Benefits of a Home Battery Backup vs Generators

No Environmental Impact & No Need to Refuel

As noted above, a primary benefit of home battery backup vs generators is there is no need for fuel. Generators are reliant upon a plentiful fuel source and contribute to greenhouse gas emissions. In addition to their environmental impact, generators are also very noisy engines that require maintenance after long periods of operation.
Home batteries either draw power from the electrical grid, or when paired with solar create a clean energy microgrid and recharge daily by storing energy from the sun. Microgrids are becoming a more common solution for delivering power to homeowners in off-grid situations because of their reliability and continuously improving communications between their essential components.
Once installed, home batteries are essentially maintenance free, are convenient because there is no need to refuel, and they have no environmental impact.

Lifetime Savings

Some states offer homeowners incentives via rebates to purchase battery systems. Creating motivation for residents to swap gas powered generators for an electrical solution helps to fend off climate change and meet state sustainability goals.

On the Federal level, the investment tax credit (ITC) which remains in effect for residential PV through 2023, offers a rebate for energy storage systems paired with solar. Although the upfront cost can be significant, it is important to look at the lifetime savings of whole home Battery backup. For example, solar alone can save the average homeowner $10 - $30K in electricity costs over the lifetime of their system.

Lumin Energy Management Platform

The Lumin energy management platform optimizes a home battery backup system for even more savings and increased energy resiliency. It resonates with homeowners who want to maximize their backup footprint in an outage and delivers flexibility in a system that traditionally is confined to backing up just a few critical loads (or things that consume energy in your home).

Because Lumin works by making ordinary circuits smart, it allows homeowners to take charge of their energy use. Instead of being hemmed to only the loads backed up in a protected loads panel, Lumin brings control and governance to the system. In addition to full and remote control from an app on your smartphone, Lumin enables homeowners to set schedules and modes that can be changed anytime - even during outages - to truly deliver the flexibility needed in a whole home battery backup system.