It is July 2018, and the module-level power electronics (MLPE) market is at a crossroads. On one side, Enphase is shipping the IQ7 series—its make-or-break seventh-generation microinverter—after a brutal two-year turnaround under CEO Badri Kothandaraman. On the other, SolarEdge is dominating the U.S. residential inverter market with the HD-Wave series, fresh off an Edison Award win in April and posting record quarterly revenue of $209.9 million.
For solar installers and electrical contractors, the decision between Enphase vs SolarEdge is not about brand loyalty—it is about wiring labor, monitoring cost, warranty risk, and whether the manufacturer will still be around to honor that warranty in 2043. Add in the architectural differences between microinverters and power optimizers, plus the looming January 2019 effective date for NEC 2017 rapid shutdown, and the 2018 specification season carries more weight than most.
This guide delivers the era-accurate specs, pricing, and installer workflow analysis you need to specify the right MLPE platform before permits go in.
The Platforms at a Glance
Enphase IQ7 Series — Microinverter Architecture
Enphase launched the IQ7 to the U.S. market in Q1 2018, and by Q2 the majority of worldwide microinverter shipments are IQ7 units. The lineup covers three models: the IQ7 for standard 60-cell modules, the IQ7+ for higher-wattage 60/72-cell panels, and the IQ7X for 96-cell modules. All three carry a 25-year warranty, 97.0% CEC weighted efficiency, and a Class II double-insulated enclosure that eliminates the equipment grounding conductor on the roof.
The IQ7 represents a genuine generational leap. Night tare loss drops to 60 mW or less. The units are lighter than previous Enphase generations, and the Q Cable system simplifies branch-circuit wiring for both portrait and landscape layouts. A single 20A branch circuit at 240V can carry up to 11 IQ7 microinverters—roughly one circuit per typical residential string.
SolarEdge HD-Wave Series — Optimized String Architecture
SolarEdge introduced HD-Wave technology commercially in 2016, and by mid-2018 the platform has roughly two years of field history with low failure rates, per DNV GL bankability reporting. The series spans seven residential models from the SE3000H-US (3.0 kW) to the SE11400H-US (11.4 kW), all featuring 99% CEC inverter efficiency and a fanless, natural-convection design on the smaller units.
HD-Wave is not a standalone inverter—it is the hub of a mandatory ecosystem. Every panel requires a SolarEdge power optimizer (P300, P370, P400/P401, or P404), which performs module-level MPPT while the inverter operates at a fixed 380Vdc string voltage. The result is panel-level monitoring and shade mitigation without the cost of a microinverter on every module.
Spec Comparison Tables
Table 1: Enphase IQ7 Lineup (July 2018)
| Model | Peak Output | Continuous | Cell Type | CEC Efficiency | Max DC Input | Warranty |
|---|---|---|---|---|---|---|
| IQ7-60-2-US | 250 VA | 240 VA | 60-cell | 97.0% @ 240V | 60V / 14A | 25 years |
| IQ7PLUS-72-2-US | 295 VA | 290 VA | 60/72-cell | 97.0% @ 240V | 60V / 14A | 25 years |
| IQ7X-96-2-US | 320 VA | ~310 VA | 96-cell | 97.0% | 80V / 14A | 25 years |
Source: Enphase IQ7 Installation Manual, 2018. Static MPPT efficiency: 99.0% weighted (EN 50530). THD: <5%. Ambient range: -40°C to +60°C. NEMA 6 / IP67 enclosure.
Table 2: SolarEdge HD-Wave Lineup (July 2018)
| Model | Rated AC Output | CEC Efficiency | Max Efficiency | Max DC Input | Max DC Power |
|---|---|---|---|---|---|
| SE3000H-US | 3.0 kW | 99% | 99.2% | 480 Vdc | 4,650 W |
| SE3800H-US | 3.8 kW | 99% | 99.2% | 480 Vdc | 5,700 W |
| SE5000H-US | 5.0 kW | 99% | 99.2% | 480 Vdc | 7,750 W |
| SE6000H-US | 6.0 kW | 99% | 99.2% | 480 Vdc | 9,000 W |
| SE7600H-US | 7.6 kW | 99% | 99.2% | 480 Vdc | 11,400 W |
| SE10000H-US | 10.0 kW | 99% | 99.2% | 480 Vdc | 15,500 W |
| SE11400H-US | 11.4 kW | 98.5% | 99% | 480 Vdc | 17,100 W |
Source: SolarEdge HD-Wave datasheets and DNV GL Bankability Report, 2018. Nominal DC input: 380 Vdc (fixed-voltage topology). Noise: <25 dBA. DC/AC oversizing: up to 155%. Standard warranty: 12 years (extendable to 20–25 years).
Table 3: SolarEdge Power Optimizers (2018)
| Optimizer | Max Input Power | Max Input Current | Efficiency | Typical Use Case |
|---|---|---|---|---|
| P300 | 300 W | 9.5 A | 99.5% | Standard residential, up to ~330W modules |
| P370 | 370 W | 10.0 A | 99.5% | Higher-power residential, up to ~400W modules |
| P400 / P401 | 400 W | 10.1 A | 99.5% | High-wattage modules, up to ~400W |
| P404 | 405 W | 11.5 A | 99.5% | Max-current variant, up to ~450W modules |
Source: SolarEdge power optimizer datasheets, 2018. Every HD-Wave inverter requires SolarEdge optimizers on every panel; the inverter performs no MPPT itself.
Table 4: Head-to-Head Platform Comparison
| Factor | Enphase IQ7 | SolarEdge HD-Wave |
|---|---|---|
| Architecture | Microinverter (one per panel) | String inverter + power optimizer (one optimizer per panel) |
| Inverter CEC Efficiency | 97.0% | 99.0% (98.5% on SE11400H) |
| System-Level Efficiency | ~97.0% (no additional losses) | ~97–98% (including optimizer losses) |
| Wiring | AC branch circuits from roof; no DC homeruns | High-voltage DC string to inverter; single AC output |
| Grounding | Class II double-insulated; no EGC required | Standard equipment grounding required |
| Voltage on Roof | Low-voltage AC (~240V) | High-voltage DC (380V string) |
| Panel Monitoring | Yes, per-panel via IQ Envoy | Yes, per-panel via optimizers |
| Monitoring Hardware Cost | IQ Envoy ~$400–500 | Built-in; free cloud portal |
| Monitoring Subscription | Free via Enlighten | Free for 25 years |
| Failure Mode | Single panel affected | Inverter failure: entire system down. Optimizer failure: single panel. |
| Warranty | 25 years (microinverter) | 12 years standard (extendable to 20–25 years) |
| Expansion | Add microinverters freely up to Envoy limit (600 units) | Limited by inverter kW rating; may need second inverter |
| Battery Path (2018) | No native option; AC-coupled third-party only | StorEdge + LG Chem RESU (DC-coupled) |
| Rapid Shutdown | Built-in (AC breaker off = shutdown) | SafeDC (optimizer voltage drops when AC lost) |
NEC 2017 and Rapid Shutdown: What Changes in 2019
The 2017 National Electrical Code (NFPA 70) is already published, and jurisdictions across the country are adopting it on staggered timelines. The critical change for solar installers is Article 690.12, which replaces the array-level rapid shutdown requirement of NEC 2014 with a module-level mandate.
Under NEC 2017, conductors inside the array boundary must be limited to 80 volts or less within 30 seconds when the rapid shutdown initiator is activated. The module-level requirement takes effect on January 1, 2019 in jurisdictions that adopt NEC 2017. Installers pulling permits in late 2018 for early 2019 completion need to specify equipment that meets the new standard now.
Both the Enphase IQ7 and SolarEdge HD-Wave are already compliant:
| Requirement | Enphase IQ7 | SolarEdge HD-Wave |
|---|---|---|
| NEC 2014 Array-Level Shutdown | Compliant (breaker-off shutdown) | Compliant (SafeDC optimizer shutdown) |
| NEC 2017 Module-Level Shutdown | Compliant (microinverter ceases output when AC breaker opens) | Compliant (SafeDC reduces DC to safe voltage at optimizer level) |
| UL 1741-SA (CA Rule 21) | Listed | Listed |
| Additional RSD Components Required | No | No |
For installers working in California under CPUC Rule 21, both platforms carry UL 1741-SA smart-inverter certification, satisfying the grid-support functionality requirements that accompany NEM 2.0 interconnection. No supplemental rapid shutdown devices are necessary with either system—a meaningful labor and materials savings compared to retrofitting a string inverter with external RSD boxes.
Labeling still matters: NEC 2017 requires a reflective "PHOTOVOLTAIC SYSTEM EQUIPPED WITH RAPID SHUTDOWN" placard with white text on a red background and minimum 9.5 mm letter height. Both Enphase and SolarEdge supply compliant labeling templates in their installation manuals.
The Installer Workflow: Wiring, Commissioning, and Monitoring
Wiring Complexity
The Enphase IQ7 system eliminates DC wiring entirely. Each microinverter outputs 240V AC, and the Q Cable trunk runs between units in portrait or landscape spacing. A single 20A branch circuit at 240V accommodates up to 11 IQ7 units, which means most residential systems use two to four AC branch circuits instead of a high-voltage DC homerun. The Class II double-insulated design means no equipment grounding conductor is required at the microinverter, reducing rooftop termination count.
The SolarEdge HD-Wave system requires a high-voltage DC string from the roof to the inverter, operating at a fixed 380Vdc. Installers must perform string-length calculations to stay within voltage and current limits, and every panel gets an optimizer that adds a mounting and connection step. The inverter itself mounts at ground level (garage, exterior wall, or basement), which keeps replacement accessible but adds a dedicated wall-penetration or conduit run.
Commissioning
Enphase commissioning requires the IQ Envoy (~$400–$500) to bridge the microinverters to the Enlighten monitoring portal. The Envoy connects to the site's router via Ethernet or Wi-Fi and auto-discovers microinverters once powered. The Enlighten Manager and Installer Toolkit apps provide per-panel production data and remote troubleshooting.
SolarEdge commissioning uses SetApp, a phone-based configuration tool launched in 2018 that replaces the previous LCD-menu method. The inverter connects via Ethernet, Wi-Fi, ZigBee, or cellular (all optional), and the free SolarEdge Monitoring Portal provides per-panel data without additional hardware. The portal is free for 25 years.
Monitoring Cost Reality
Enphase monitoring is free through the Enlighten platform, but the IQ Envoy is a required upfront purchase. SolarEdge monitoring is also free, and because the communication hardware is built into the inverter, there is no separate gateway to buy. For a 20-panel system, the $400–$500 Envoy cost adds roughly $20–$25 per panel to the Enphase monitoring stack. Over a 25-year system life, that difference fades, but it matters on tight bids in 2018.
Expansion Limits
Enphase systems scale panel-by-panel up to 600 microinverters per Envoy—well beyond any residential need. Mixing panel wattages, cell types, and orientations is unrestricted because every panel operates independently.
SolarEdge expansion is capped by the inverter's AC rating. Adding panels beyond the inverter's DC/AC oversizing limit (up to 155%) requires either a larger inverter or a second HD-Wave unit. Because every panel must have a SolarEdge optimizer, partial upgrades or third-party panel additions are not possible without buying into the optimizer ecosystem.
Financial Stability Context: The Elephant on the Roof
In 2018, the enphase vs solaredge decision is not purely technical—it is also a bet on which company will survive to honor a 25-year warranty.
Enphase: The Comeback Story (Unfinished)
Enphase reports Q2 2018 revenue of $75.9 million, up from $69.97 million in Q1, with GAAP gross margin improving to 29.9% and non-GAAP margin reaching 30.5%. The company is still posting a GAAP net loss of $3.7 million this quarter, but the trajectory is positive. CEO Badri Kothandaraman, who joined in April 2017, has cut costs, restructured supply chains, and bet the company on the IQ7.
The stock climbed back above $1 in 2017 after a delisting scare, and management is guiding toward the company's first GAAP profitable quarter by Q4 2018. Component shortages, however, are already constraining supply by more than $10 million in Q3—a risk that could delay the turnaround. For installers, the 25-year microinverter warranty is only as good as the balance sheet behind it.
SolarEdge: The Dominant Incumbent
SolarEdge is in a radically different position. The company posted Q1 2018 revenue of $209.9 million, up 82% year-over-year, with a GAAP gross margin of 37.9% and inverter shipments of 800 MW AC. Full-year 2018 guidance points to roughly $937 million in revenue and 3.9 GW AC of shipments. CEO Guy Sella emphasizes operational excellence, and the company's mandatory optimizer ecosystem generates locked-in recurring revenue.
For installers, SolarEdge's financial strength is reassuring. A 12-year inverter warranty is standard, with extensions available to 20 or 25 years. The company is profitable, growing, and deeply entrenched in the U.S. residential market.
What This Means for Your Bid
If you are specifying Enphase in mid-2018, you are betting on a turnaround. The IQ7 is a compelling product, but Enphase is not yet out of the woods. If you are specifying SolarEdge, you are buying from the market leader with two years of proven HD-Wave field data and a balance sheet that can absorb warranty claims. Neither choice is wrong, but the risk profiles are not equivalent.
Buyer-Impact Block: What the Choice Means for the Installer
Landed Cost per Watt
At wholesale, an Enphase IQ7 runs roughly $130–$150 per unit and the IQ7+ about $150–$170. For a 6 kW system using 20 panels, the microinverter hardware bill is approximately $2,600–$3,400 plus the IQ Envoy at $400–$500. A comparable SolarEdge system uses one SE6000H-US inverter (~$1,500–$1,800 wholesale) plus 20 optimizers at ~$30–$50 each (~$600–$1,000). The hardware delta is narrow, but Enphase edges higher on a per-watt basis when the Envoy is included. Add the January 2018 Section 201 tariff (~$0.16/W on modules) and the typical 6 kW residential system lands at roughly $18,500–$23,400 before the 30% federal ITC, or $13,000–$16,400 after.
Wiring Labor
Enphase wins on roof labor: no DC homeruns, no string calculations, no grounding conductor at the unit. The Q Cable system snaps together quickly. SolarEdge requires DC string design, optimizer mounting on every panel, and a dedicated inverter location with ventilation clearance. On complex roofs with multiple faces, Enphase saves hours of conduit and cable management.
Monitoring Subscriptions
Both platforms offer free monitoring, but Enphase requires the IQ Envoy gateway (~$400–$500 upfront). SolarEdge builds monitoring into the inverter with no separate hardware purchase. For budget-conscious bids, the Envoy is a line item that SolarEdge avoids.
Warranty Risk
Enphase offers a 25-year microinverter warranty—longer than SolarEdge's 12-year standard—but Enphase's financial stability is still recovering. SolarEdge's shorter warranty is backed by a profitable, growing company. Installers must weigh the longer coverage against counterparty risk.
Expansion Flexibility
Enphase allows panel-by-panel expansion up to 600 microinverters per Envoy, with no restrictions on mixing panel types or orientations. SolarEdge expansion is limited by inverter capacity; oversizing up to 155% is possible, but beyond that a second inverter is required.
Battery Upgrade Path
In 2018, SolarEdge holds a clear advantage. The StorEdge interface works with LG Chem RESU batteries in a DC-coupled configuration on compatible HD-Wave models. Enphase has no native battery product; the previous AC Battery is being phased out, and the next-generation platform is not yet shipping. Enphase customers who want storage must go AC-coupled with a Tesla Powerwall 2 or LG Chem RESU, with no Enphase integration.
Frequently Asked Questions
What is the difference between Enphase IQ7 and SolarEdge HD-Wave?
Enphase IQ7 is a microinverter architecture with one inverter per panel, 97% CEC efficiency, a 25-year warranty, and no native battery option. SolarEdge HD-Wave is a string inverter paired with power optimizers, delivering 99% inverter CEC efficiency, a 12-year warranty, and a battery-ready path through the StorEdge interface with LG Chem RESU.
Which is more efficient: Enphase IQ7 or SolarEdge HD-Wave?
The SolarEdge HD-Wave inverter alone achieves 99% CEC efficiency, compared to 97% for the Enphase IQ7. However, the SolarEdge system requires power optimizers on every panel, and full system efficiency including optimizer losses is approximately 97–98%. In real-world conditions, both platforms deliver comparable energy yields.
How much did Enphase IQ7 cost per panel in 2018?
In mid-2018, wholesale pricing for the Enphase IQ7 microinverter is approximately $130–$150 per unit, while the higher-output IQ7+ runs roughly $150–$170. Per-panel monitoring requires the IQ Envoy, which adds approximately $400–$500 to the system cost.
Does SolarEdge HD-Wave require power optimizers?
Yes. The SolarEdge HD-Wave inverter is designed exclusively for use with SolarEdge power optimizers. The inverter performs no MPPT itself; all maximum power point tracking happens at the module level via the optimizers. Available models in 2018 include the P300, P370, P400/P401, and P404.
Was Enphase financially stable in 2018?
Enphase is recovering but still carries risk. In Q2 2018, the company reports revenue of $75.9 million but a GAAP net loss of $3.7 million. Gross margin is improving—reaching 29.9% in Q2 and trending toward 30%—and management expects the first GAAP profitable quarter by year-end. Still, installers should weigh warranty continuity against the company's turnaround progress.
What does NEC 2017 require for rapid shutdown?
NEC 2017 Article 690.12 requires module-level rapid shutdown instead of the array-level shutdown under NEC 2014. Inside the array boundary, controlled conductors must drop to 80 volts or less within 30 seconds. The module-level requirement becomes effective January 1, 2019 in jurisdictions that adopt NEC 2017. Both the Enphase IQ7 and SolarEdge HD-Wave meet the standard.
Can you add batteries to either system in 2018?
SolarEdge offers a native battery path through the StorEdge interface, which works with LG Chem RESU batteries in a DC-coupled configuration. Enphase does not offer a native battery product in 2018; the previous-generation AC Battery is being phased out, and the next-generation platform is not yet available. Enphase systems that need storage must use an AC-coupled third-party battery such as the Tesla Powerwall 2 or LG Chem RESU.
Which platform is better for shaded or complex roofs?
Both platforms handle shading and complex roofs well. Enphase IQ7 provides true panel-level MPPT and inversion, so any mix of panel types and orientations is acceptable. SolarEdge HD-Wave provides panel-level MPPT through power optimizers on every module, with a fixed-voltage string inverter. For extremely complex roofs with multiple azimuths and tilts, Enphase offers slightly more design flexibility.
Where It Stands Today
This section bridges the 2018 comparison to the current product landscape.
The Enphase IQ7 and SolarEdge HD-Wave defined the 2018 installer debate—but both ecosystems have evolved dramatically. Today, the Enphase IQ8 series offers grid-forming Sunlight Backup without batteries, enabling daytime power during outages through a radically faster processing architecture. The SolarEdge Home Hub integrates DC-coupled battery storage as a native home energy manager, evolving the HD-Wave platform into a full residential energy ecosystem.
Battery parity has arrived: Enphase now ships the IQ Battery 5P with LFP chemistry, while SolarEdge offers the Energy Bank line. Panel wattages have climbed from ~300W to 400–500W+, and both platforms have narrowed their cost delta. The market itself has reversed—Enphase is now the dominant microinverter brand, while SolarEdge has expanded from inverters into comprehensive home energy management.
For the latest Enphase microinverters and storage, browse our Enphase collection. For SolarEdge Home Hub inverters, power optimizers, and batteries, visit our SolarEdge collection.
Get a Bulk System Quote
Portlandia Electric Supply stocks both Enphase and SolarEdge platforms for solar installers and electrical contractors. Whether you are bidding a 6 kW residential job or a 15 kW commercial rooftop, our team can spec the right inverter, optimizer, or microinverter package with competitive wholesale pricing.
Browse related products: Solar Inverters · Power Optimizers · Residential Solar Panels
