The latest addition to Enphase’s line of micro-inverters is here: the Enphase IQ7+. The IQ7+ has been upgraded to a higher 290W output (up from 280W), which allows you to pair it with slightly larger panels than the previous model allowed.
The Enphase IQ line remains our go-to micro-inverter pick for grid-tie systems thanks to their
Keep reading for our complete Enphase IQ7+ review. We’ll go over pricing, specs, ideal application, and pros and cons of the IQ7+.
IQ7+ Price and Specs
- Price: $147 apiece (plus $18 apiece for mandatory Q Cable connectors, totaling $165 per unit)
- Wattage: 290 watts
- Peak Efficiency: 97.6%
- Warranty: 25 years
- Input voltage: 16-60V DC
- Output voltage: 240V AC
- Works with: 60-cell and 72-cell modules
The IQ7+ package costs $158 per panel, which is great if you want to start small and ease your way into solar. Once you grow beyond about 10 panels, the scales start to tip in favor of SolarEdge HD-Wave systems as the more cost-effective option.
The price difference is minor for a system this size—$1.45/watt for the IQ7+ system vs. $1.42/watt for the HD-Wave system—and the ease of installation for the IQ7+s often justifies the higher price tag.
However, as systems grow in size, the price difference gets more pronounced. You don’t see too many larger systems (10kW+) built on micro-inverters because they are less cost-effective at a larger scale.
Learn more about which inverter is right for your system:
The IQ7+ is sized to output 290 watts of power. Realistically, you can (and should) pair them with slightly larger panels, up to the 325-335W range. This is to account for natural efficiency losses in the system. As a rule of thumb, you’ll lose about 10% of the panel wattage due to inefficiencies caused by factors like temperature.
You also want to oversize panels to stay closer to 290 watts of output during sub-optimal production conditions. This could occur to shading or other obstructions, but it also keeps you closer to max wattage during off-peak times of day (when the sun isn’t directly overhead).
However, you don’t want to go too large with your panels, because you’ll waste any overhead production during peak periods. The Enphase spec sheet suggests the IQ7+ is compatible with panels up to 440W, but that’s overkill given any power generated above the 290W cap is wasted. We’ve found that 335W is a good upper limit for the rated output of the IQ7+.
Why use micro-inverters?
To answer this question, let’s look at the limitations of string inverters.
String inverters set restrictions on your panel string size—the number of panels that can be wired together and plugged into a single inverter input.
Panel strings typically contain 6-10 panels, which helps the inverter operate at peak efficiency. Too many panels (or too few) and your inverter won’t work properly.
The other major limitation is that panels in a string are linked together. When one panel in the string suffers reduced output (due to shading or technical malfunction), every panel in the string drops to match that reduced output.
You may own a string of 330W panels, but if a single panel in the string falls to 250W production, every panel in that string is going to produce 250W of power. That’s an 800W production loss over a 10-panel string.
Systems with power optimizers (like the SolarEdge HD-Wave) mitigate this issue somewhat by enabling each panel to produce independently. But the HD-Wave is still restricted by minimum string size requirements, and shading across the string can still cause it to fall below the minimum input voltage.
Micro-inverters are designed to work around these limitations.
Pairing a micro-inverter with a panel essentially creates a self-contained, single-panel solar system. It doesn’t matter how many panels you buy—each panel in the system functions independently.
Start with a single panel hooked into an IQ7+ if you want. This allows you to start small and offset a portion of your utility bill as soon as possible, then expand the system as budget allows.
Micro-inverters are also the most shade-tolerant option. Shade on one panel will never impact the rest of your system. You don’t have to worry about a group of panels meeting a minimum string voltage, because each one functions as a self-contained system.
Finally, micro-inverters are easier to install. Simply chain each Q cable from one unit to the next, with the final wire terminating in a junction box. They’re easier to install than string inverters because micro-inverters utilize common household AC wiring, which is readily available and simple to install.
Read more: Micro-Inverters vs. String Inverters
Pros of the Enphase IQ7+
No String Sizing Requirements
With micro-inverters, you don’t have to worry about how many panels you group together. This means they are less impacted by shading. They are also easier to expand. Start with one panel and one IQ7+ if you want. This allows you to offset a portion of your utility bill as soon as possible, then expand the system as budget allows.
One thing we really like about the IQ7+ is how extremely easy they are to install. There’s an input for your panels and an output to chain the Q cables from unit to unit, with the last one plugging into your junction box.
From the junction box to your breaker panel, you’ll install standard household AC wiring, which is much easier and cheaper to install compared to the DC wiring used with string inverters and optimizers. This can save you a lot of time, money and hassle messing around in your attic.
It’s also dead simple to tell at a glance whether your system is functioning properly, thanks to a light on the unit that changes color based on its status:
- Green: Everything is working.
- Yellow: Micro-inverter works, but is not communicating with IQ Envoy monitoring system.
- Red: Micro-inverter is not working and panel is not producing power.
Compatible with 60-cell and 72-cell panels
Standard solar panels contain either 60 or 72 cells. Since there’s no difference in performance or cost-per-watt between the two options, it’s nice to have access to both when designing your system. The IQ7+ is configured to work with both options.
The standard IQ7 only works with 60-cell panels due to its lower voltage and wattage.
With the IQ7+, you can choose to work with 72-cell panels if you want. For example,
Since 72-cell panels are physically larger, you’ll be installing fewer panels and micro-inverters. That means less racking material, fewer holes in the roof, and fewer connections to hook up, which makes installation quicker and easier on the whole.
This is a big one. The 25-year warranty on the IQ7+ far surpasses the SMA Sunny Boy (10 years) or SolarEdge HD-Wave (12 years). That’s important because it matches the 25-year warranty that comes standard on Tier 1 solar panels in today’s market.
With string inverters, you’ll need to budget for at least one inverter replacement over the life of the system. You’ll have to choose whether to pay more up front for an extended warranty, or cover the replacement out of pocket when the time comes.
The IQ7+ comes with a standard 25-year warranty. If one of your micro-inverters ever malfunctions at any point in your system’s lifetime, you’re covered for a free replacement. No maintenance fees or hidden ownership costs to worry about.
Compliant With Rapid Shutdown Codes And Smart Inverter Regulations
In the event of an emergency at your home, first responders must be able to quickly and safely turn off your system to negate the risk of electrical shock from live DC circuits coming from the array. The IQ7+ is fully compliant with the most recent national rapid disconnect codes (NEC 2017 690.12).
It also meets the definition of a “smart inverter” under California’s Rule 21. Smart inverters interface with the utility grid to control when and how your system feeds electricity to the grid. This helps the utility smooth the demand curve and deliver more reliable power during peak usage periods.
The IQ7+ is code-compliant and cleared for installation in all 50 states (unlike the Magnum MicroGT, which cannot be used in California or Hawaii because it does not meet local code requirements).
Cons of the IQ7+
Monitoring Not Included
While we like the IQ7+’s simpler design and ease of installation compared to its predecessors, we’d like to see the monitoring system become a streamlined part of the package.
Right now, you have to buy the Enphase IQ Envoy to be able to monitor your system’s output. The IQ Envoy is a separate unit that requires extra work during installation and commissioning, which only adds more labor to the installation process.
What’s more, the SMA Sunny Boy and SolarEdge HD-Wave come with monitoring platforms built into the inverter at no additional charge. In that context, it’s hard to swallow the idea of paying an extra $500 to add functionality that comes standard with other systems.
More Parts = More Failure Points
The more parts there are in your system, the greater the chances one of them will fail. If you have 20 micro-inverters doing the job of one string inverter, it’s 20x more likely something in your system malfunctions and needs to be replaced.
Even though the IQ7+ is warrantied for 25 years, it still takes time and energy to make a claim and replace it if it fails. Most people just want their system to work without ever thinking about it.
Distributed micro-inverter systems introduce more potential failure points and a higher likelihood of maintenance somewhere down the line. It’s especially important to keep this in mind for roof-mounted systems, which are more difficult (and expensive) to access for repairs.
But the distributed nature of micro-inverters is a double-edged sword. If a string inverter fails, the entire system stops producing. A failed micro-inverter only takes a single panel out of commission.
So while micro-inverters make replacements more likely, they also isolate failure, allowing the majority of your panels to continue producing energy while you replace the defective unit.
Higher Cost Per Watt
Of all the inverter configurations, micro-inverters are the most expensive from a cost-per-watt perspective. As of the time this article was last updated (1/2/20), here’s how much it would cost to route 20 Astronergy 345W panels into three different inverter setups:
- with an SMA Sunny Boy: $9,618
- with a SolarEdge HD-Wave: $10,225
- with Enphase IQ7+ micro-inverters: $10,309
For full-scale systems, string inverters are more cost-effective option. If you can build in full sunlight, the Sunny Boy costs about 20% less than a micro-inverter system.
Even the HD-Wave, with built-in monitoring and individual optimizers that give you panel-level control, costs less than an IQ7+ setup.
Enphase IQ7+: The Verdict
We recommend the IQ7+ in the following scenarios:
- You want to start small and expand later
- You want a system that is easier to install
- You need a system that is highly shade-tolerant
For a more cost-effective option, especially for larger scale systems, you would be better served with the SMA Sunny Boy or the SolarEdge HD-Wave.