A solar battery offers homeowners the ability to store energy. This can be helpful for power outages and avoiding higher utility prices during “peak time” for utility companies.
If you don’t have a battery, your solar panels can sometimes produce more energy than you need. When that happens, they just send it to the grid. If you do have a battery, that extra energy is stored and can be used when your panels aren’t producing as much or if there are issues with the grid. But not everyone needs or wants a battery so, is a solar battery right for you?
It’s a pretty simple question, but the answer is a little more complicated than you’d think! Each option has pros and cons, so we’re going to break it down so you can pick which is best for you.
Why a battery might be the better option for you:
- You Live Off the Grid – If you currently live remote and where you can’t easily connect to the power grid, then a battery becomes your only option (makes the decision pretty easy if you ask us!)
- Grid Independent – We get it… it sounds amazing to be free of utility companies, so if this is your goal with adding solar to your house, then a battery is a great choice!
Why a battery might not be the choice for you right now:
- Expensive – Since the technology is still newer, the cost of batteries is pretty high. A high-quality battery will likely be between $8,000 and $20,000. Just like solar panels, as the technology grows, we expect the price to drop.
- No DIY – Getting a battery means hiring an installer. Current technology for solar batteries requires a trained installer or electrician to ensure that installation and connection to the power grid are done safely. This also adds another cost to the price tag.
Top 2 Options for Solar Batteries
There are several companies selling solar batteries right now, but it’s important to pick the right one for you. Several factors can determine the decision, including, price, kWh output, efficiency, battery life, and of course, cost.
Two of the current leaders in solar batteries are Tesla & Enphase. While they both offer great products, we’re going to break down the pros and cons of each!
Tesla Home Battery System
Tesla is one of the biggest brands out there. They currently offer their Powerwall 2 that launched in November 2020 and the Powerwall + that was released in April 2021.
- Size & Usage – Both the Powerwall 2 and Powerwall+ have 13.5 kilowatt-hours (kWh), but you are able to purchase multiple and connect them if your energy needs are higher. The roundtrip efficiency for both is 90%, which means that you get 9 kWh of output for every 10 kWh of input.
The Powerwall+ comes with a new inverter & integrated breaker. It also has an increased power output at a 9.6 kW peak with a continuous 7.6 kW, while the Powerwall 2 offers 5.6 kW.
Battery Life – Powerwalls are lithium-ion batteries that use Nickel Manganese Cobalt (NMC) chemistry. They have high energy densities which means they can store a higher amount of energy for the battery size. However, this comes with a bigger risk of thermal runaway, which means the internal heat can cause chemical reactions in the battery.
- Price – With all the necessary parts added on, the Powerwall adds up to $8,500. With installation, the average is between $12,000 and $16,000.
It’s pretty common for owners to have to upgrade their electrical panel before installation so there’s another hidden cost. Also, you can only get a Powerwall when you purchase Tesla’s solar panels. So if you already have your panels installed, this isn’t a great option.
The other leader in solar batteries is Enphase. The company currently offers 4 different options: the IQ Battery 3, 3T, 10, and 10T. The newer versions (3T and 10T) were recently released to combat growing demand and supply chain issues, so the only difference is dimensions and weight.
- Size & Usage – The 3 & 3T have an energy capacity of 3.36 kWh while the 10 & 10 T have 10.08 kWh. While that’s less than the Powerwalls, it does give more flexibility to your solar needs. Similar to Tesla, homeowners can buy multiple to meet the energy needs for their house.
Both batteries have a round-trip efficiency of 96% meaning that for every 10 hours of charging, there are 9.6 hours of output.
Battery Life – Enphase batteries promote a 10-year life expectancy. Also a Lithium-Ion battery, however, Enphase uses Lithium iron phosphate (LFP) chemistry. This is the safer option compared to Nickel Manganese Cobalt. LFP batteries promote a safer cathode material for better thermal stability which makes the devices last longer compared to NMC.
- Price – The IQ Battery 3 and 3T are about $2,300-$3,000. The 10 and 10T are $7,000-$9,000. These prices don’t include installation though, so owners can expect to pay a few extra thousand for a professional installer depending on where they live.
Enphase recently announced that they are releasing a better battery option sometime in the next year. The new battery will feature a longer lifespan and only requires a handful of cords to plugin which makes it ideal for DIY customers!
Solar Wholesale’s Recommendation
If you have to have a battery right now, we recommend choosing an Enphase battery. The IQ Batteries offer safer chemistry which often leads to a more durable product. They also have more flexibility for a homeowner with two different sizes.
However, we at Solar Wholesale pride ourselves on offering the highest quality products possible that our customers can install themselves. We aren’t currently selling batteries with our solar kits until the batteries on the market meet our standards.
Until then, we have Enphase inverters that will make it easy for homeowners to install a battery once the improved batteries are available.