A solar battery empowers your home to take full advantage of your residential solar system. As the sun doesn’t shine every day, a solar battery allows you to store the energy generated by your panels so you can use them at night, during blackouts, or in other low-to-no sunlight conditions.
When it comes to solar batteries, Enphase and Tesla are two of the leading players in the solar energy space. Enphase has grown to be an absolute juggernaut in the microinverter market in the past decade. Tesla, on the other hand, has propelled home solar into the mainstream since its 2016 acquisition of SolarCity.
The Enphase IQ 10 (formerly branded as the Enphase Encharge) and the Tesla Powerwall 2 are two of the most sought after solar storage products available right now. This article will delve into the most important features of both the Enphase IQ 10 and Tesla Powerwall 2, including:
- power and capacity
- off-grid performance
- weather performance
For the sake of simplicity, we will focus on Ephase IQ 10 and the Tesla Powerwall 2, as these two compare closely with each other. It’s worth noting, however, that both Enphase and Tesla offer several other solar battery options.
Enphase vs. Tesla: Capacity and Power
A solar battery’s capacity, often indicated in kWh, refers to the total amount of energy a battery can store at any given time. On the other hand, a solar battery’s power, indicated in kW, refers to the amount of energy that a battery can consistently release over an extended period of time.
High capacity solar batteries can store more energy and can power your home for a longer period of time without needing to recharge. High-power solar batteries, on the flipside, can provide more energy to power multiple heavy-duty appliances at once, but often at the expense of burning through the battery’s total capacity at a much faster rate.
The Enphase IQ 10 has 10.8 kWh capacity and 3.84 kW power. Additionally, the Enphase IQ 10 is capable of releasing 5.7 kW peak power for 10 seconds at a time.
The Tesla Powerwall 2 has 13.5 kWh capacity and 5.0 kW power. The Tesla Powerwall 2 is capable of releasing 7.0 kW peak power for 10 seconds at a time.
Enphase vs. Tesla: Efficiency
A solar battery’s efficiency is a product of 3 factors: depth of discharge, round trip efficiency, and battery degradation overtime.
Depth of discharge (DoD) refers to how long a solar battery can provide power before it needs to be recharged. For instance, if you have a solar battery that needs to be recharged every time it hits 10%, then it has a 90% DoD. A high-quality solar battery would typically have a DoD of over 95%.
Round-trip efficiency (RTE) refers to how much power a solar battery can deliver compared to how much it can store. For instance, if you have a solar battery that requires recharging every time 70% of its total capacity is spent, then it has a 70% RTE.
Battery degradation refers to the amount of degradation that happens to a solar battery throughout its lifespan. Solar batteries naturally degrade—lose a portion of their ability to hold charge—over time. Most leading manufacturers offer long-term warranties to guarantee that their batteries will only incur an acceptable amount degradation over a period of time.
The Enphase IQ 10 has a 100% depth discharge, a round-trip efficiency of 89%, and battery degradation of 3%.
The Tesla Powerwall 2 has a 100% depth discharge, a round-trip efficiency of 90%, and battery degradation of 3%.
Enphase vs. Tesla: Chemistry
Safety is an important consideration, especially since most solar batteries are used for home applications. The chemical composition of solar batteries can, in so many ways, dictate how safe they are.
Most solar batteries are made up of either lead acid or lithium-ion. Between the two, lithium-ion batteries have more advantages than lead-acid batteries, including having a higher DoD and longer lifespan; li-ion batteries are also a lot more compact and are lighter than lead acid batteries.
Most leading manufacturers of solar batteries tend to favor lithium ion. There are two popular types of li-ion solar batteries: lithium iron phosphate (LFP) and nickel manganese cobalt (NMC).
The Enphase IQ 10 is a cobalt-free lithium-iron-phosphate (LFP) solar battery. As it is cobalt-free, the Enphase IQ 10 naturally stays cool and eliminates the risk of any thermal runaway defects, which reduces the risk of fire and causes less wear and tear on the battery. Because the Enphase IQ 10 uses passive cooling, there is no need for external fans, and are therefore less susceptible to mechanical failure.
The Tesla Powerwall 2 is a nickel manganese cobalt oxide (NMC) solar battery. As it is an NCM battery, it tends to produce a significant amount of heat, which increases the risk of thermal runaway. To offset this, Tesla has incorporated a liquid cooling system that allows the Powerwall 2 to offload heat quickly and prevent overheating; this safety feature is also designed to extend the lifespan of the battery.
Enphase vs. Tesla: Off-Grid Performance
The off-grid performance of solar batteries is often underappreciated, but it is extremely important, especially if you live in an area that experiences frequent power outages
The Enphase IQ 10 is designed to continue to regulate solar output in the event that the grid shuts down. In most cases, solar panels will shut off during a power outage as part of the grid’s standard safety protocol. By using the Enphase Empower Smart Switch, however, your solar system can temporarily disconnect from the grid and draw from power from your solar battery instead, which allows you to maintain power in your home.
The Tesla Powerwall 2 doesn't have the ability to monitor charging and effectively regulate solar power during a power outage. When the grid is down, the Tesla solar system is designed to turn off for 5 minutes in order to discharge excess energy before it can pull power from the Powerwall 2.
Enphase vs. Tesla: Weather Performance
The weather performance of solar batteries should be a key consideration when looking for a consistent, reliable, and robust solar battery.
The Enphase IQ 10 is designed to generate and provide power during extreme weather conditions. It can detect weather changes and prioritize charging in order to store enough energy to make it through the storm. The Enphase IQ 10 also comes with the Enphase Storm Guard mobile app that pulls weather information directly from the National Weather Service.
The Tesla Powerwall 2 is designed to withstand extreme weather conditions. A solid option for those who are living in extreme-weather areas, the Tesla Powerwall 2 can anticipate severe weather and adapt its charging accordingly. The Tesla Power also comes with the Tesla Storm Watch mobile app that obtains weather information from the National Weather Service.
Enphase vs. Tesla: Monitoring
Choosing solar batteries that make it possible for you to actively monitor your system is important, as this will ultimately allow you to optimize your power usage and lower your grid consumption.
The Enphase IQ 10 comes with the Enphase Enlighten mobile app that makes it easy to keep track and monitor both your solar panel production and energy consumption in real-time. Enphase’s all-in-one monitoring solution is designed to help you make smarter energy usage while maximizing your energy savings.
The Tesla Powerwall 2 comes with the Tesla App that allows you to examine how your Tesla solar system produces and consumes energy at any given time. Tesla's complete energy monitoring solution is also designed to help you monitor your system’s performance, configure your consumption for maximum efficiency, update your solar firmware, and troubleshoot your system when necessary.
Enphase vs. Tesla: Warranty
A solar battery, like any other battery, will degrade overtime and partially lose its ability to store energy. As discussed earlier, most leading solar manufacturers offer long-term warranties to guarantee that their battery will perform at an acceptable level over a given period of time.
The warranty is a key consideration when deciding on a solar battery as it legally holds the manufacturers responsible in the event that your battery malfunctions or fails to perform as it was advertised.
The Enphase IQ 10 comes with a 10-year warranty that guarantees 70% percent capacity over 10 years and 4,000 cycles. Enphase also gives a 5-year warranty extension for an additional cost.
The Tesla Powerwall 2 comes with a 10-year warranty that guarantees 70% percent capacity over 10 years and 3,200 cycles.
Enphase vs. Tesla: Pricing
Price shouldn’t be the sole determining factor when you’re deciding on a solar battery, but it is an essential consideration nonetheless.
The Enphase IQ 10 costs between $8,000 and $11,000, including installation costs. Enphase also offers the smaller Enphase IQ 3 if you just need a small boost in capacity to meet your additional energy requirements. The Enphase IQ 3 would cost you $4,000 and $5,000, including installation fees
The Tesla Powerwall 2 costs around $10,500, including installation fees. The Tesla Powerwall 2 comes in one size only, so you will have to purchase a full 13.5 kWh Powerwall 2 if you want an additional boost in capacity. The second Powerwall 2, however, would just cost you $6,500 instead of the full $10,500.
Enphase vs. Tesla: The Bottomline
Both Tesla Powerwall 2 and Enphase IQ 10 are top-of-the-line home solar batteries. Both are made by trusted solar manufacturers that set the standard in residential solar energy solutions.
Both Tesla Powerwall 2 and Enphase IQ 10 provide reliable backup power for your home—and you can’t go wrong with either one.
Both Tesla Powerwall 2 and Enphase IQ 10 come with a wide array of advanced features and functionalities, and both carry their own sets of benefits and advantages. It’s ultimately up to you to prioritize these based on your energy goals and requirements.