How to choose the best solar battery for your needs
Solar battery technology is one of the core pieces of the electrification and solar power revolution that’s happening right now. Reliable and affordable battery technology, after all, not only helps keep the lights on when the power is out, it can help store solar energy for use when the sun isn’t shining.
Read more about solar batteries for residences in our guide, Solar Batteries for Home: A Comprehensive Guide.
Of course, no battery storage article would be complete without mentioning the Inflation Reduction Act (IRA), which unambiguously makes battery storage eligible for the Investment Tax Credit (ITC) — now at 30% until 2032.
Even plug-in electric vehicles, which use similar energy storage, are playing a significant role in accelerating the advancement of the solar battery.
All of this is leading to significant improvements in battery technology, and drops in battery storage pricing. Likewise, more homeowners are considering battery storage as part of their solar projects. Let’s look at some of the decision factors to consider when helping a customer determine the right battery for their home.
Are batteries worth the cost?
For solar customers truly looking to make the most of their PV system, a quality home solar battery can be a good choice. There’s no sugarcoating that they’re pricey — usually between 10,000 and 20,000 installed — but if a solar customer can afford it, the benefits of installing a solar battery are substantial. And, as mentioned earlier, solar batteries are eligible for a 30 percent federal solar investment tax credit, and many local utilities offer incentives as well, which brings the cost down considerably.
Considering that solar batteries play triple-duty as a power generator for emergencies, can help lower energy bills over the long run, and decrease a home’s carbon footprint, they are often well worth the investment if the adopter plans on keeping a home long term. The payback period for solar batteries can be as little as five years, give or take a year or two depending on other factors such as total system capacity and design and available incentives. Of course, some benefits of solar batteries — such as peace of mind and resiliency — are priceless to some solar customers, and should also be a factor in deciding if solar batteries are worth it.
Of course, knowing ROI and showing ROI to customers are two different things. Aurora’s Energy Storage tool lets you model battery load, system configurations and customization, and more for customers, so they can easily see the benefits.
In addition, t he Rapid advancements in solar battery technology mean that newer batteries are entering the market while the older ones are still on the shelves. From traditional lead-acid, today’s solar shoppers now have a wealth of battery types, technologies, and sizes to choose from.
There have been numerous advancements in the electrical energy storage industry in the past decade. One of the most notable is the development of modular systems, such as the Tesla PowerWall. These types of batteries have greatly made energy storage more flexible, easy to install and transport, and more affordable to maintain.
If you are looking at battery storage for a solar project, the first thing you need to know is how to choose the right one.
Choosing a battery system
Most people, particularly homeowners, venture into solar power with limited know-how. The market has adapted to their needs by generalizing what a buyer should “expect” when investing in a solar system. This information is not always accurate.
The wealth of solar battery options can make it quite a daunting task. While most people go for a one-size-fits-all approach, this may not always be the best choice.
The problem with one-size-fits-all batteries
There are three good reasons why you should not go for a one-size-fits-all type of solar battery:
- The technology the battery uses is rarely ever emphasized. Most one-size-fits-all batteries use lead-acid technology to store energy. This is not the best technology in the market.
- These batteries may be bulky in size, but they often lack power storage capacity. The cost rarely ever justifies the power capacity.
- These standardized solar batteries are almost always either oversized or undersized. The undersized batteries cannot meet power output demand. The oversized batteries, on the other hand, are not always fully charged, especially in the winter.
The one-size-fits-all battery is touted as the ideal choice for most people because a majority of buyers rarely ever know what to look for. However, it often trades various features and capabilities to meet the minimum requirements of different use cases.
Solar battery specs
All solar batteries are made differently. Some manufacturers use robots, while others assemble batteries manually. The form of quality control can affect the quality of the batteries. Some manufacturers are known to use more lead and heavier grids, which impacts the performance of the cells in the battery. Most importantly, some brands of batteries are tested exhaustively for safety and performance while others are not.
As a result, it is not uncommon for batteries with similar specifications to have different performance and lifespans. Finding the right batteries for your solar setup may mean the difference between good and poor power system performance. It may also mean the difference between negligible or high maintenance.
Here are the most important considerations you should have on your checklist when shopping for a solar battery.
Battery capacity
Batteries are rated in amp-hours, or simply amps. The indicated power rating is typically the fully developed capacity of the battery. This means that it may take tens to hundreds of charging cycles before the battery can reach the indicated full capacity. In other words, it can be misleading to test your battery after only a few cycles of charges.
You do not need to understand the physics behind electricity to estimate your power needs or properly size your batteries. If you already use power from the grid, this guide can help you estimate your power consumption based on your electricity bills.
As a rule of thumb, always estimate your peak power requirements using amp-hours. A battery rated 100 amp-hours, for instance, can theoretically put out 1 ampere of electric energy for 100 hours or 10 amps for 10 hours. When selecting a solar battery, understanding your power needs is the key to choosing the battery with sufficient energy storage.
Note that batteries with long warm-up cycles before reaching full capacity are more likely to outlast batteries that tout a high initial capacity.
Lifespan and charge/discharge cycles
The lifespan of a battery is a crucial factor that manufacturers compete on when designing robust solar batteries. The design process often focuses on making the battery resist heat and cold cycles to deliver peak performance for longer. The type of battery technology also plays a significant role in determining the lifespan of the battery.
Three factors that affect the longevity of a battery that you should check when shopping for one are:
- Depth of discharge: This is the extent to which the battery is discharged or used, relative to its capacity. Since batteries degrade as they are used, their capacity deteriorates over time.
- Cyclic life: This is the number of charge and discharge cycles of the battery. During regular use, flooded batteries typically last for between 300 and 700 cycles. Gel batteries can store and deliver peak power for as many as 500 to 5000 cycles. Lithium batteries can last for up to 200 cycles.
- Temperature: The chemical activity inside batteries increases with temperature. To extend the lifespan of your solar batteries, install them in a temperature-controlled room.
Flooded vs. sealed batteries
Solar batteries can be broadly categorized into two: flooded and sealed.
Flooded batteries are the standard lead-acid batteries used in vehicles and off-grid solar installations. They are affordable, and because they can be easily cleaned and serviced, have longer lifespans. When in use, these batteries generate small amounts of hydrogen gas.
Sealed batteries are also known as VRLA (valve regulated lead acid) batteries. They cannot be serviced or maintained because they are sealed. A charge controller maintains the fluids and plates inside the battery to prolong their lifespan. These batteries do not emit hydrogen gas when in use.
Peak power output
Solar power batteries can be classified by their kilowatt peak or kWp. kWp is the theoretical peak power output of the system in ideal conditions. The peak output is more of a measure of comparison than an absolute unit.
When choosing a solar battery, the kWp rating indicates the highest amount of power it can output at its best performance: the higher the peak power output rating, the better the battery.
Round-trip efficiency
The round-trip efficiency of a battery is the amount of energy that can be computed as a percentage of the energy used to store it. For instance, if 100 kWh of electricity is fed into a battery, and it can only output 90 kWh, the round-trip efficiency of the battery would be 90% (90 kWh / 100 kWh x 100).
Always go for batteries with a higher round-trip efficiency because they are more economical.
Ambient working temperature
Ambient temperature is the average air temperature surrounding the battery, or the temperature of the room in which the battery is installed. The rating indicates the optimum temperature under which the battery will perform normally.
Backup Battery vs. Generator: Which Emergency Power Option Is Better?
You can keep the lights on with both of these backup power sources. But battery storage is the better, and more expensive, option. Here’s how to compare and decide which is better for you.
Taylor Freitas is a freelance writer and has contributed to publications including LA Weekly, Safety.com, and Hospitality Technology. She holds a B.A. in Print and Digital Journalism from the University of Southern California.
In this article:
There are various types of backup power systems on the market, and each serves the same primary purpose: keeping your lights and appliances on when the power goes out.
In the past, fuel-powered standby generators (also known as whole house generators) have dominated the market for backup power supply, but reports of a risk of carbon monoxide poisoning have led many people to search for alternatives. Battery backups have emerged as a more eco-friendly and potentially safer alternative to conventional generators.
Battery backups and generators are different devices. Each one has a particular set of advantages and disadvantages, which we’ll cover in the following comparison guide. Keep reading to find out about the main differences between battery backups and generators and to decide which option is right for you.
Battery backups
Home battery backup systems, such as the Tesla Powerwall or the LG Chem RESU, store energy, which you can use to power your house during an outage. Battery backups run on electricity, either from your home solar system or the electrical grid. As a result, they’re much better for the environment than fuel-powered generators. They’re also better for your wallet.
Separately, if you have a time-of-use utility plan, you can use a battery backup system to save money on your energy bills. Instead of paying high electricity rates during peak usage hours, you can use energy from your battery backup to power your home. In off-peak hours, you can use your electricity as normal.- but at a cheaper rate.
Generators
On the other hand, standby generators connect to your home‘s electrical panel and kick on automatically when the power goes out. Generators run on fuel to keep your electricity on during an outage.- typically natural gas, liquid propane or diesel. Other generators have a dual fuel feature, meaning that they can run on either natural gas or liquid propane.
Certain natural gas and propane generators can connect to your home’s gas line or propane tank, so there’s no need to refill them manually. Diesel generators, however, will need to be topped up in order to keep running.
Battery backup vs. generator: How do they compare?
Pricing
In terms of cost, battery backups are the pricier option upfront. But generators need fuel to run, which means that you’ll spend more over time to maintain a steady fuel supply.
With battery backups, you’ll need to pay for the backup battery system upfront, as well as installation costs (each of which are in the thousands). Exact pricing will vary based on which battery model you choose and how many of them you need to power your home. However, it’s common for an average-sized home battery backup system to run between 10,000 and 20,000.
For generators, the upfront costs are slightly lower. On average, the price of purchasing and installing a standby generator can range from 7,000 to 15,000. However, remember that generators require fuel to run, which will increase your operating expenses. The specific costs will depend on a few factors, including the size of your generator, which type of fuel it uses and the amount of fuel used to run it.
Installation
Battery backups earn a slight edge in this category since they can be mounted to the wall or floor, whereas generator installations require a bit of additional work. Regardless, you’ll need to hire a professional for either type of installation, both of which will require a full day of work and may cost several thousand dollars.
Aside from setting up the device itself, installing a generator also requires pouring a concrete slab, connecting the generator to a dedicated fuel source and installing a transfer switch.
Maintenance
Battery backups are the clear winner in this category. They’re quiet, run independently, don’t produce any emissions and don’t require any ongoing maintenance.
On the other hand, generators can be quite noisy and disruptive when they’re in use. They also emit exhaust or fumes, depending on which type of fuel they use to run.- which may irritate you or your neighbors.
Keeping your home powered
As far as how long they can keep your home powered, standby generators easily outperform battery backups. As long as you have enough fuel, generators can run continuously for up to three weeks at a time (if necessary).
That’s simply not the case with battery backups. Let’s use the Tesla Powerwall as an example. It has 13.5 kilowatt-hours of storage capacity, which can provide power for a few hours on its own. You can get extra power out of them if they’re part of a solar panel system or if you use multiple batteries in a single system.
Expected lifespan and warranty
In most cases, battery backups come with longer warranties than standby generators. However, these warranties are measured in different ways.
Over time, battery backup systems lose the ability to hold a charge, much like phones and laptops. For that reason, battery backups include an end-of-warranty capacity rating, which measures how effective a battery will hold a charge by the end of its warranty period. In Tesla’s case, the company guarantees that the Powerwall battery should retain 70% of its capacity by the end of its 10-year warranty.
Some backup battery manufacturers also offer a throughput warranty. This is the number of cycles, hours or energy output (known as throughput) that a company guarantees on its battery.
With standby generators, it’s easier to estimate lifespan. Good-quality generators can run for 3,000 hours, as long as they’re well maintained. Therefore, if you run your generator for 150 hours per year, then it should last about 20 years.
Which battery backup is right for you?
Across most categories, battery backup systems come out on top. In short, they’re better for the environment, easier to install and cheaper to run long-term. Plus, they have longer warranties than standby generators.
With that said, traditional generators can be a good option in some cases. Unlike battery backups, you only need a single generator to restore power in an outage, which brings down the upfront costs. Plus, standby generators can last longer than battery backup systems in a single session. As a result, they’ll be a safer bet if the power is out for days at a time.
What is a solar battery?
A solar battery is an energy storage option for those with solar panel systems. With the increased use of solar power, solar batteries are more popular with homeowners who want to offset electricity costs and those living or camping off-grid.
Solar generators and portable solar chargers are types of solar battery storage systems. While solar generators are typically affixed to their location — usually houses, campers or boats — a portable solar charger is a smaller, often hand-held device typically used to charge phones or other electronics. Some solar generators are available as all-in-one kits, but you can buy components separately as well.
Types of solar batteries
There are multiple battery types to consider when choosing solar batteries. Which type is best varies based on your needs and whether you prioritize cost efficiency, safety or environmental impact.
Deep-cycle battery The term “deep cycle” refers to the battery’s ability to complete a discharge-recharge cycle several times. Deep-cycle batteries are designed to keep a steady flow of power over an extended period. Thick lead plates help prolong the battery’s life. Lithium-ion, flooded and gel batteries are types of deep-cycle batteries. Lithium-ion battery Lithium-ion batteries are an excellent choice because they are relatively low maintenance and easy to install. The benefits of a lithium-ion solar battery include higher energy density, less weight and increased life span. Lithium-ion batteries are considered a revolution in home energy storage solutions.
Lithium batteries have the added advantage that their voltage stays relatively constant as it discharges. In a lead-acid battery, the voltage decreases as the battery discharges. So, in order for a lead-acid battery to maintain its output, the current draw increases as the voltage drops. This, in turn, discharges the lead-acid battery more quickly. Lithium batteries do not have this drawback.
Lithium-polymer battery Similar to lithium-ion, lithium-polymer batteries are more resistant to issues like overcharge or electrolyte leakage. They are also more expensive and don’t usually last for as many cycles as lithium-ion batteries. Flooded lead-acid battery Also known as wet-cycle batteries, flooded lead-acid batteries contain liquid in an open container and disperse hydrogen gas. These batteries are cheaper but require more maintenance because the battery must be kept upright and well-ventilated. The battery also needs to be monitored and regularly refilled with distilled water. Sealed lead-acid battery This valve-regulated battery is considered the maintenance-free option in sealed lead-acid (SLA) batteries. They are designed to keep the battery from reaching its gas-generating limit while charging, which prevents water depletion and gas dispersal. This also means that the battery can never be completely charged. Nickel-cadmium battery Ni-cad batteries have a long lifespan if properly maintained. This is one of the more rugged battery types available, but they occasionally require a full discharge to keep their longevity. Be aware that cadmium is toxic, so this battery cannot be disposed of in landfills. Saltwater battery If you’re looking for clean and environmentally friendly energy, a saltwater battery is a good choice. Like lead-acid batteries, saltwater batteries offer a natural alternative for clean energy storage. The electrolyte is saltwater, which is nontoxic and nonflammable. These batteries are maintenance-free and have good longevity. Solar gel battery A gel battery, or gel cell, is similar to a sealed lead-acid battery. This battery also uses a gel electrolyte. Unlike other lead-acid batteries, you don’t need to keep it upright — it handles movement very well, which makes it a Smart choice for campers, vans and boats.
How do solar batteries work?
Solar batteries can be installed alongside your solar panel system to store the excess energy it produces. When the panels don’t produce power at night, you can use the stored energy instead. Many solar battery storage options come with an inverter to convert the stored DC power to the AC power you need, but some require you to buy the inverter separately.
You can then use it as a solar battery generator to power electricity needs. This helps people looking to mitigate electricity costs, prepare for disasters or be completely off-grid. Homes still on the electrical grid can offset their consumption with backup energy and run on battery power until the storage is depleted.
The amount of electricity a solar battery can deliver at once is measured in kilowatts (kW). Kilowatt-hours (kWh) refers to the total amount of energy utilized over an hour. The U.S. Energy Information Administration (EIA) states the average American home consumes 901 kWh per month, or 30 kWh a day. With a battery that provides 2.5 kWh, you would need 12 batteries for sufficient daily power.
Since solar batteries self-discharge, the stored solar energy depletes over time. The rate of self-discharge depends on the type and age of the battery. Newer batteries typically deplete at a rate of 1% to 2% per month, whereas older batteries could deplete by as much as 2% per week.
Residential solar panel arrays don’t usually require solar batteries. Still, solar panel battery storage lowers your utility bills, protects you from power outages and reduces your carbon footprint. If you already have solar panels, solar batteries work to store energy for the future. However, most popular solar batteries like Tesla Powerwall and LG Chem RESU aren’t designed to go completely off the grid.
FAQ
Small solar batteries run between 200 and 5000,000. However, a quality battery for residential solar energy storage can cost up to 7,000 or more. When comparing solar battery prices, you should also consider the cost of battery storage per kWh (kilowatt-hour), which ranges from 400 per kWh to 750 per kWh.
Most homeowners need between two and five solar batteries to effectively power a house. Depending on your energy needs, you can connect several batteries in a series or parallel battery bank with interconnecting cables. Solar batteries are stackable, meaning that you can install multiple batteries with your solar storage system to reach the right capacity for you.
Solar panels are expensive because of the materials required to produce them. are expected to drop as solar technology advances.
Generally, fully charged solar batteries should power your home for 12 to 24 hours. Variables like your household energy consumption, the capacity of your batteries and whether you’re connected to an electrical grid determine exactly how your long solar batteries last. A solar battery’s lifespan can be anywhere between five and 15 years. You can extend a battery’s life with proper maintenance and by protecting it from extreme temperatures.
A battery bank is a collection of batteries that are connected. A battery bank allows for more power storage than you get from a single battery.
Comparing A Solar Battery System To A Home Generator
When the grid experiences a massive outage, it can create dangerous conditions for everyone in the area. Home and business owners looking for more reliable power even during an outage event might look into diesel- or propane-powered generators, or installing a solar array with a battery backup.
As an installer, it’s important to know the pros and cons of both in terms of necessary equipment, cost, reliability, capacity, and more.
We’ll explore the difference between the solar batteries and generators below, and highlight some of the top performers in both categories on the market today.
Comparing A Solar Battery System To A Home Generator
Comparing generators to solar batteries is a case of apples and oranges. Installers can help clients understand the differences between the two options and, by examining the clients’ energy usage, can recommend which if any option makes sense for them.
Both applications will be a considerable investment, so installers should be prepared to discuss the payback period and costs associated with each option.
In this section, we’ll review the pros and cons for both batteries and generators to help you determine what’s best for your client’s situation.
Solar Battery Backup System
Solar systems equipped with solar battery storage make it possible for clients to store excess energy generated during the day and draw on it during nighttime or during an outage. Solar batteries store and discharge energy generated by a solar installation. Some batteries are not built for grid connectivity, however, and may only be appropriate for completely off-grid installations. Installers can assess a client’s energy needs and savings goals to help determine the best configuration. Some common options include:
- Off-grid DC-coupled batteries: This type of system is often used to power both remote properties and recreational vehicles. They normally come with built-in inverters to convert direct current (DC) to alternating current (AC) power.
- Off-grid AC-coupled batteries: These systems perform the same basic function as their DC counterparts – but the conversion process happens prior to reaching the batteries themselves.
- Grid-tied AC-coupled batteries: This arrangement is more popular for residential storage needs. The inverter technology is already built in, making these ideal for both new PV installations and retrofits. Just keep in mind that for grid-tied connections, solar permitting and utility approvals are usually required.
- Grid-tied DC-coupled solar batteries: These batteries use inverters capable of accepting high voltage loads. Although poorly suited for off-grid applications, their compact size makes them a favorite among homeowners.
Another important consideration is the depth of discharge (DoD), which is the percentage of discharged power relative to the battery’s total storage capacity. If a battery can hold 10 kilowatt-hours of solar capacity, a DoD of 75% means that you can’t reliably draw more than 7.5 kilowatt-hours of clean energy. It’s similar to how modern computers ship with “500 gigs” of storage even though the operating system and pre-installed programs take up some of that hard drive space.
As a general rule, the higher the depth of discharge, the more solar power a homeowner can store and use. So aim for DoDs that are 95% or higher.
Below are just some of the core benefits your residential clients can enjoy when combining solar battery backup technology with their PV panels:
- Generators have been around for a while, making them relatively easy to buy, install, service, and repair
- They’re dependable, able to provide reliable power day or night – regardless of weather conditions
- Many generators are “portable,” allowing homeowners to move them whenever and wherever they need emergency backup power
Although generators have their plus sides, they also have many drawbacks:
- They rely on fossil fuel, which means C02 and other greenhouse gasses are released during operation
- In addition to being smelly, generators are also noisy – which is just another kind of pollution
- Generators remain idle for most of the year – only being used during the occasional blackout. And for many homeowners, this is a poor use of space and resources
- Generators have substantial maintenance requirements, complete with scheduled servicing, trips to the gas station, and frequent top-ups
Last but not least, a typical generator is not an investment. Whereas solar batteries recharge themselves with free energy from the sun, gas generators need constant refueling. And this means they never pay for themselves. Instead, generators carry ongoing costs – both for homeowners and the planet as a whole.
Do You Need Solar Panels To Have A Battery?
Solar energy is not required to install a battery at your home. The key difference is that you cannot “refuel” a battery without sunlight during a grid failure like you can refuel a gas generator (assuming you have access to fuel). A battery can be charged from grid power, but you are always at the mercy of your utility pricing by going this route.
With solar, you can charge and recharge, maintenance-free. There is a common misconception that solar only works in the sunny “hotspots” in the United States. However, there are enough quality sun hours a day to provide a large portion of households in the United States with enough energy to fully charge a battery.
How Much Does a Whole Home Battery Backup System Cost?
Whole home battery backup systems are making their way into homes and replacing the noisy, pollutant-emitting fossil fuel generators that used to be standard.
Battery backup systems allow homeowners to weather even extended power outages and blackouts. With the right equipment, a whole home backup power solution can power an average household for at least a day and up to a week. If your battery backup system allows solar charging, you can add solar panels to generate clean, renewable electricity indefinitely.
Whole home battery backup systems typically cost between 3000 and 15,000 before installation. The vary widely depending on power output and storage capacity, home size, average electricity usage, and other factors.
Factors That Affect the Cost of a Whole House Battery Backup System
Many factors come into play when pricing out a whole-house backup system. These include:
- Battery size
- Power output capacity
- Installation
- Charging options
- Electricity Generation
Battery Size
Battery storage capacity is a significant factor in the cost of a whole-house backup system. Larger systems can store more electricity and provide backup power for longer, but they also cost more. Battery cost is often the largest share of the total system cost. Increasing the battery size or adding additional storage will almost always increase the overall cost of the system.
However, the cost per kilowatt-hour (kWh) of electricity storage decreases as the battery size increases. It may be more cost-effective to install a more extensive system to increase the backup time and reduce the need for supplemental backup power sources, such as a traditional fossil fuel generator.
Determining the optimal battery size for your home backup needs is based on additional factors like:
- Your average energy consumption,
- How many appliances you need to run during a blackout
- Their starting and running watts
- The duration of the outage you want to be prepared against
According to the U.S. Energy Information Administration, the average household uses 886 kWh of electricity per month (or about 30 kWh per day). To maintain this level of electricity consumption, you’d need a backup battery system size of 30 kWh just to run your house as normal for one day during a blackout.
However, you can take steps during a blackout to reduce energy usage, decreasing the battery storage capacity you need to install and maintain. To minimize your electricity usage, keep these tips in mind:
- Only open the refrigerator and freezer when necessary.
- Use air conditioning and heating systems as little as possible.
- Use led lights (which consume far less electricity than conventional light bulbs) and flashlights instead of your home’s lighting system.
Power Output Capacity
Batteries store power as DC electricity. You’ll need an inverter or an all-in-one battery backup solution like EcoFlow’s portable power stations to convert the energy stored in your battery into AC (household) electricity.
Battery storage capacity and power output capacity are not the same things. Storage capacity is the maximum amount of energy that your battery can hold at any given time. Storage capacity is typically measured in watt-hours (Wh) or kilowatt hours (kWh).
Power output capacity is the maximum amount of electricity your battery backup system can output at once. Power output capacity determines what kind of appliances you can run based on their electricity demands — usually measured in watts (W) or kilowatts (kW).
You can determine which appliances your battery backup system can run simultaneously by adding up the running wattage of each device you want to operate. One crucial thing to keep in mind is that many large appliances require more wattage to start up than they do to operate. This is called starting watts or surge power.
Here’s how to determine your power output needs step by step.
- Identify the wattage requirements of your appliances. Survey the starting and running wattage requirements of the appliances and devices you plan to plug into the generator. You can usually find the wattage requirements labeled on the appliance, but we’ve also compiled the starting and running watts of typical household appliances in the table below.
- Convert volts/amps to watts. If your appliance’s power requirements are in volts or amps, you can calculate an appliance’s running watts with this equation:
Volts (V) x Amps (A) = Watts (W)
- Count the running watts of your appliances. Add up the running watts of the appliances you plan to use — does the total exceed the running watts listed on your generator? If so, you should consider buying a generator with more output capacity.
- Factor in starting watt requirements. Identify the appliance with the highest starting wattage. Add that appliance’s starting wattage to the running wattage total.
- Calculate the sum. That final number is the total starting watts you need from your generator. As discussed above, to avoid overloading your generator, do not exceed its starting watts rating.
Which Whole House Battery Backup System Is Right for You?
There are various whole-house battery backup systems on the market to choose from. You can build one from scratch step-by-step. Or you can customize a setup that meets your family’s needs by selecting products from EcoFlow’s Smart Home Ecosystem.
When determining the best option, remember it’s about much more than just price.
Other significant factors to consider are the backup battery system’s expected lifespan, recharge time, ongoing maintenance requirements, battery chemistry and efficiency, and warranty.
Expected Lifespan
You may be tempted to choose the cheapest available whole house battery backup system, but what if you have to replace it in just a year or two?
A battery’s estimated lifespan is usually measured by cycle life. Each time you discharge and recharge the battery is called a cycle.
The number of cycles the battery will last without diminishing in efficiency is largely determined by its chemistry.
Battery Chemistry and Efficiency
The cheapest backup battery chemistry option is lead acid. The basic technology behind lead acid batteries is over 150 years old. These are the batteries you’ll find in TV remotes, flashlights, and old cars.
Lead acid batteries might get the job done, but not for long. Typically, lead acid batteries are only rated for a few hundred cycles, as opposed to new battery technology — like lithium iron phosphate (LFP/LiFePO4) — which can last for thousands of cycles without losing efficiency.
Lithium ion and LFP batteries have drastically reduced in price in recent years as the technology has become standard for solar generators, electric vehicles (EVs), and whole-home battery backup.
For example, the latest generation of lithium iron phosphate batteries in EcoFlow’s RIVER 2 Series and DELTA Pro portable power stations can last 6500 cycles — over a decade of average use.
Over the long term, you’ll save money by investing in modern battery technology like LFP.
Nickel-cadmium (Ni-Cad) batteries are also a better choice than lead acid, but they pale in comparison to LFP.
Maintenance
Lead acid battery systems require constant maintenance, such as adding distilled water every 2 to 4 weeks. Also, lead acid batteries should never be discharged below 50% capacity as it will lead to permanent damage. They must be stored in well-ventilated areas and may not function in extreme cold or heat.
Lithium iron phosphate batteries do not require regular maintenance, can be deeply discharged without harm, and operate in a much wider temperature range.
Warranty
Many cheap or low-quality battery backup systems will not include an extended warranty. This usually indicates that the manufacturer doesn’t stand behind their products.
Reputable companies will offer extended warranties for their products.
For instance, EcoFlow provides five-year warranties to their portable power stations, including the Delta PRO models in their Whole Home Backup Power Solution.
Final Thoughts
Whole home battery backup systems are an excellent way to prevent your family from being affected by power outages. With a big enough battery bank, you can even keep larger appliances running, such as refrigerators, heating and cooling systems, and more.
The Whole Home Backup Power Solution is a great way to get started on making your house more energy-resilient. The system is expandable, so you can always add more battery and output capacity down the line.
Best of all, solar panels are easily integrated into the system to generate clean, renewable power indefinitely.
EcoFlow is a portable power and renewable energy solutions company. Since its founding in 2017, EcoFlow has provided peace-of-mind power to customers in over 85 markets through its DELTA and RIVER product lines of portable power stations and eco-friendly accessories.