A home power backup system must provide a consistent and reliable source of energy that can be accessed quickly in the event of a power outage. Even though both systems are used as a home power backup, generators and batteries work very differently, and each system has its own pros and cons. While battery technology has made significant advancements over the past 20 years, generators have been around for decades and have historically been the primary source of electricity during a power outage. However, constantly improving battery technology is seeing battery banks becoming more efficient and more common as home backup power sources.
Battery-powered backup systems, known as “battery banks,” can be used to power your home when the electrical grid goes down. The banks store electricity taken from the power grid or produced by an off-grid solar array. There are several types of batteries that have and can be used in a battery bank, but the three most common types used for backup power include lead-acid, lithium-ion and lithium iron phosphate.
Types of Batteries
- Lead acid batteries haven’t changed much since they were first invented by Gaston Planté in 1860. Lead acid batteries are not very efficient for power backup systems as this type of battery can only be discharged to a maximum of 70 percent of its capacity, or its lifespan will be significantly reduced. While these are not the most efficient choice, lead-acid batteries are the cheapest battery option.
- Lithium-ion batteries are of the same type used in most cell phones and computers. These have a very long life span and can be drained and recharged hundreds of times. Lithium iron phosphate is currently considered the best type of battery for backup energy storage as these batteries have an even longer lifespan than lithium-ion and can be recharged over 1,000 times.
There are two basic types of power generators, and each has its advantages.
- Fuel Generators
Fuel-powered generators have been around since the 1960s and originally ran on gas and kerosene. Fuel generators can now run on propane and natural gas as well, and these two fuel types are the favored options for home backup systems as these have plumbed gas lines and eliminate the need for refueling. The issues with fuel generators are you will have no power if you run out of fuel.
- Solar Generators
Solar generators are somewhat of a misnomer as the devices do not actually “generate” electricity but rather capture and store energy from the sun. Solar generators use a small solar panel, and the storage unit contains a battery and inverter to power small AC devices. However, these types of generators have a very limited power capacity.
Generators typically cost less upfront, but the cost of fuel over the long term will add up. While battery backup systems typically have a greater upfront cost, the need to buy fuel is eliminated. Battery systems can also reduce utility costs by drawing power from the bank during peak use hours when electricity rates are usually higher. The cost for a battery backup system will vary based on the type of battery and the size of the battery bank.
Battery banks are typically considered the better choice for the environment as they do not burn fossil fuels. However, there are some concerns about the toxic effects of battery components if the used units are not properly handled.
Battery banks may be seen as the more dependable home power backup option simply because they do not rely on an outside fuel source and will continue to produce power in the event of a fuel shortage.
Battery banks and generators both have their places for home backup power systems. Generators are typically the less expensive upfront option and are a necessary backup solution for those living off-grid where a solar system is the primary source of power. On the other hand, a quality battery bank can save you money in the long term and has the advantage of dependability which is always the primary consideration when preparing for an electric grid failure. If you are trying to decide which is the better option for you, carefully consider your own personal needs, budget and long-term costs before making a decision.