Home batteries for renters: What you need to know

Whether you're looking to lower your electricity usage during peak electricity hours or have a backup power supply in the case of an outage, home batteries are becoming increasingly popular. However, most energy storage systems require installation and electrical wiring, making it difficult for people who rent or own a condo to take advantage of these benefits. Some companies have recently acknowledged this gap, launching plug-in battery solutions that don't require installation by an electrician – this is making home batteries more accessible to everyone, regardless of whether you have access to your main electrical panel.

Generally, when you purchase an energy storage system, it's installed with an inverter that integrates into your home's energy system. If you have solar panels, you can charge your battery directly with solar energy, or, for a standalone home battery, you can set it with electricity from your utility company. The energy output from the battery is then wired straight into your main electrical panel (or a smaller, critical loads panel if necessary). You'll continue using your devices at home as usual – though in the case of an outage, you'll likely only have a subset of circuits that are powered, depending on the size of your battery. Additionally, according to EnergySage installers, installation costs typically account for about 13 percent of your energy storage system's cost–there is a lot of electrical work to do after all–meaning you can save a lot with a battery that doesn't require installation.

With plug-in batteries, you can do just that! These batteries work by plugging into your wall outlet, similar to any other device in your home. You then charge them with your home's electricity – whether that be from solar panels or just from the grid. Once your battery is charged, any devices you want to run with it typically plug directly into outlets built into the battery itself. Generally, you can expect to pay considerably less for a plug-in battery than an energy storage system, but they also provide less (often much less) backup power.

There are two primary reasons why you'd want a plug-in battery: decreasing your electricity bill and resiliency.

Decreasing your electricity bill

How can a plug-in battery lower your electricity bill? In many areas of the U.S., you pay more for electricity during certain times of the day when the demand is higher – think, a hot afternoon when everyone's running their air conditioning. With a plug-in battery, you can charge the battery at night when electricity is cheaper and use it to run devices during times when electricity costs more: essentially, it's a form of arbitrage that allows you to pay less for using the same amount of energy.

Resiliency

Let's say you've just experienced a power outage: your WiFi is down, you're unable to charge your phone and your work computer, and you may even be losing out on payable work hours. On top of that, you're trying to hold off on opening your refrigerator for as long as possible to prevent your food from spoiling. With a plug-in battery, you'll be able to keep a few crucial devices running for a certain period of time to avoid the biggest losses experienced during a power outage. But remember: the more (and higher energy consuming) devices you run, the shorter your plug-in battery will last.

Plug-in batteries aren't for everyone, but they do make sense for a lot of people! A few questions you'll want to answer when deciding if you're a good fit for a plug-in battery include:

1. How much backup do you want? If you're looking for full home backup, a plug-in battery isn't the right solution. You're better off installing a solar plus energy storage system, especially if you have control over your home's electricity (i.e., access to the main electrical panel).

2. Do you live in an area with time-of-use (TOU) rates, demand charges, or real-time pricing? If you live in an area where you pay more for electricity when it's in higher demand, there's a better chance that you'll benefit from a plug-in battery.

3. Do you experience frequent power outages? If you lose power frequently, you're probably a good candidate for a plug-in battery (especially if you can't or don’t want to install an energy storage system). You'll be able to back up your most important devices for a few hours to a couple of days (depending on the device you're running).

More and more companies are starting to launch plug-in battery solutions – so you might be wondering how to compare the different available options! We'll explain some of the key things you should consider before choosing a plug-in battery:

Battery chemistry

Most plug-in batteries hitting the market are lithium-ion but can have two different chemistries: Lithium Nickel Manganese Cobalt Oxide (NMC) or Lithium Iron Phosphate (LFP). While both chemistries come with their own pros and cons, generally, LFP batteries provide greater capacity and come with a longer lifespan, while NMC batteries are more power dense and take up less space.

Usable capacity & power rating

When considering the performance of a plug-in battery, you'll want to look at the usable capacity and power rating. Usable capacity is measured in kilowatt-hours (kWh) and represents the maximum amount of energy that your battery can store on a full charge. Continuous power is measured in kilowatts (kW) and is defined as the maximum amount of electricity that your battery can output consistently. Instead of (or in addition to) reporting continuous power, some plug-in battery companies report peak power (also measured in kW), which is the maximum amount of power that can be output over a short period of time – peak power tends to be higher than continuous power.

Stackability & portability

Let's say your plug-in battery doesn't quite provide enough backup power for your needs – the good news is that some are stackable, meaning you can connect multiple batteries to increase your capacity. If the battery you're interested in isn't stackable, you can also just purchase additional separate batteries and plug them into more outlets – but this will generally take up more space (and outlets!).

One consideration here is that the more batteries you stack, the less portable your plug-in battery system becomes. Some plug-in batteries are designed to be extremely portable, so you can use them on a camping trip, as backup power for an electric vehicle (EV), or just move them from outlet to outlet as you need (say, you want to charge your refrigerator during one outage and your bedroom's window AC unit during another).

Number of charging ports

With most plug-in batteries, you plug any devices you want to charge directly into the battery itself – so it's important to consider how many charging ports you have access to in one battery. But also remember that the more devices you have plugged in at once, the faster your battery will run out of power.

Affordability

In general, home energy storage systems come with quite a hefty price tag, but you can expect plug-in batteries to be more affordable. Most plug-in battery systems will cost somewhere between $800 and $2,500.

Warranty

While they may be cheaper than energy storage systems, plug-in batteries are still an investment – so you want to make sure your investment is protected! Warranty terms vary across plug-in batteries, ranging anywhere between two and ten years in length. Your warranty may also include a cycles clause or the number of times you charge and discharge the battery. Generally, the warranty term will end whenever you reach the number of warrantied years or the number of cycles (whichever comes first).

Plug-in batteries are not yet widely available, but the following companies all offer products that you can either purchase or pre-order/reserve now.

blip

Highlights: affordability, battery chemistry

blip energy just launched their first plug-in battery product – the blipOne – in November 2021. This LFP battery comes with a 2.2 kWh capacity, 2.0 kW continuous power, and four AC charging ports. It also comes with a three-year warranty and can be easily transported (it has built-in wheels!). Using blip's app, you can add in your utility information so it automatically charges when electricity rates are low and discharges when they're high. The blipOne has a sleek design and sits on your floor, resembling a small air purifier. Most importantly, blipOne is very affordable at only $800! How does it come with such a low price tag? blip uses repurposed batteries to decrease the battery's cost and make it more sustainable!

You can order the blipOne now via blip's Kickstarter campaign – they're expecting batteries to be delivered in summer 2022.

WATTS

Highlights: stackability, warranty

The WATTS Battery is an interesting plug-in battery solution in that it can also serve as an energy storage system, depending on how you install it. If you can't or don't want to have it integrated into your home's electrical panel, you can just plug it into an electrical outlet – no permits or installers are required. Each WATTS Battery module comes with 1.2 kWh total capacity and 1.5 kW peak power. However, if you're looking to increase your capacity, you can stack up to 30 modules (they stack easily on top of one another, similar to legos) for a total of 36 kWh! You can bring battery modules with you on the go and use them to charge your EV or charge appliances at home with the two AC charging ports and two USB outlets. This plug-in NMC battery solution is backed by an impressive 10-year warranty (or 4,000 cycles), but you should expect to pay upwards of $2,000 for it.

You'll have to purchase a WATTS Battery through a distributor, but be sure to check out their product in the EnergySage Buyer's Guide.

EcoFlow

Highlight portable solar integration.

If you're looking to easily purchase a plug-in battery today, good news! The EcoFLOW DELTA Max Portable Power Station is available now. This NMC battery comes with six AC charging ports and two USB ports and provides 2.016 kWh of capacity and 2.4 kW of peak power (for the larger model). Importantly, it also comes with an 800-watt solar charging input – meaning you can charge the DELTA Max with EcoFlow's portable solar panels in the event of a prolonged outage! This battery costs $2,000 and is backed by a two-year warranty.

If you're interested in the EcoFlow DELTA Max, you can purchase it directly through EcoFlow.

Orison

Highlights: monitoring, warranty

The Orison Panel+ is the most complicated of the plug-in batteries on our list – but it is also very unique! The Panel+ hangs on your wall and plugs directly into your wall outlet, but instead of having to plug devices directly into the battery, you can continue to plug in your devices as usual. This plug-in battery uses an energy monitor – which you have to purchase and install in your breaker box, though it doesn't require an electrician – to determine when to charge and discharge the battery to maximize savings based on utility information. The caveat here is that when the grid is down, you'll still need to plug any devices you want to keep charged directly into the Panel+, so you need to make sure you place it near big devices that you want to keep charged (like a refrigerator).

The Orison Panel+ offers 2.2 kWh capacity and 1.8 kW continuous power – and you can stack up to six for a maximum capacity of 13.2 kWh per outlet. This battery is also backed by a 10-year (or 5,000 cycles) warranty. If you're looking to purchase this plug-in battery, you can reserve it directly through Orison for $2,499 (including the required energy monitor).

Even if your plug-in battery doesn't integrate directly with rooftop solar, you can still charge it with solar energy! In fact, going solar is the best way to maximize your energy savings and avoid paying a premium for electricity when it's in peak demand. On the EnergySage Marketplace, you'll receive up to seven quotes from our network of pre-screen solar installers. By comparing these quotes, you'll be able to find a system that meets your needs at the right price.

Community solar is a way to take part in environmentally-sustainable solar projects in your area. By subscribing to receive credits from a local solar farm, you can help ensure that your electricity consumption is offset by solar energy. Visit our community solar marketplace to learn about local projects and make the most informed decision for your energy use.