Panels get most of the attention when people choose brands, but the inverter is what converts panel output into power the house can use. It works every day the sun is up, and it contains more electronics than anything else in the system. If any component needs repair or replacement over the system's life, the inverter is the most likely candidate.
19Energy installs three main inverter brands: HUAWEI, Solis and Deye. This comparison is based on what the manufacturers publish. It doesn't rank one brand as the best, because each suits different jobs.
Before comparing brands, get the type right
Choosing the type of inverter matters more than choosing the brand, because the fix for the wrong type is replacing the whole unit.
| Type | What it does | Suits |
|---|---|---|
| On-grid | Converts panel output for use in the house; the surplus flows to the grid. No power during outages | Homes and businesses with high daytime use that don't need backup |
| Hybrid | Everything on-grid does, plus it takes batteries to store power for the evening or for outages | Anyone who needs backup, or may add batteries later |
The other thing that has to match is the number of phases. The inverter must match the building's supply: a single-phase home uses a single-phase inverter, and most three-phase buildings use a three-phase inverter. There's more in our article on single-phase vs three-phase.
If you're not adding batteries now but think you may want backup in a few years, choosing a hybrid inverter from the start lets you add batteries later without replacing it. If you're sure you won't need backup, an on-grid inverter is the better value.
Manufacturer warranties
These figures are the manufacturer's product warranty on the unit, not the installation warranty, and they can differ by model and by country. The figure that applies to you is the one in the warranty document for the model you receive.
| Brand | Product warranty | Notes |
|---|---|---|
| HUAWEI | 10 years | SUN2000 series; can be extended to 15 or 20 years |
| Solis | 5 years | 5 years standard; can be extended to 10, 15 or 20 years if requested within the first 5 years · counted from commissioning or 6 months after leaving the factory, whichever comes first |
| Deye | 10 years | The manufacturer's datasheet says the warranty period depends on where the inverter is installed; check the warranty document for your unit |
Solis's standard warranty is half as long as the other two. That's worth knowing before you choose, and if you want longer cover you have to buy the extension within the first five years. If you see "up to 10 years' warranty" quoted for Solis, ask whether the extension is already included in the price.
Manufacturer warranties generally don't cover damage from external events or incorrect installation. Solis's terms, for example, explicitly exclude lightning, flood, power surges and improper installation. Surge protection and a good mounting position are therefore part of what makes the warranty usable in practice.
Models and capabilities
| HUAWEI | Solis | Deye | |
|---|---|---|---|
| Monitoring app | FusionSolar | SolisCloud | Deye Cloud |
| Single-phase hybrid (example series) | SUN2000-KTL-L1, with LUNA2000 batteries | S6-EH1P, low-voltage batteries | SUN-SG04LP1, low-voltage batteries (40–60 V) |
| Three-phase hybrid (example series) | SUN2000-KTL-M1 | S6-EH3P, high-voltage batteries | SUN-SG04LP3 |
| Backup during outages | L1 series needs a battery and SmartGuard, per the manufacturer | S6-EH3P series switches to off-grid in under 10 ms, per the manufacturer | Supports off-grid operation; peak output of twice the rated power for 10 seconds |
| Generator pairing | Needs to be designed case by case | S6-EH3P series supports generator connection | Datasheet states support for storing energy from a diesel generator |
Model availability varies by country, and some models in this table may not be sold in Thailand. The table reflects each series' capabilities according to the manufacturer; the exact model used on your job must be named in the quote.
HUAWEI
HUAWEI designs the inverter, LUNA2000 batteries and accessories as one manufacturer's set, so everything is monitored in a single FusionSolar app. The thing to know: if you want backup during outages, HUAWEI states that the single-phase L1 series needs both a battery and a SmartGuard unit, so the quote should include that item — not just the battery.
Solis
Solis offers on-grid and hybrid models in both single- and three-phase, monitored through the SolisCloud app. The trade-off to weigh is the 5-year standard warranty, shorter than the other two. If you choose Solis, decide on the warranty extension at the outset and note the five-year deadline.
Deye
Deye's single-phase hybrid inverters use low-voltage batteries. The datasheet states support for off-grid operation, a peak output of twice the rated power for 10 seconds — which helps when pumps or compressors start — and support for pairing with a diesel generator. That makes it a good fit for jobs where backup power matters. Monitoring is through the Deye Cloud app.
Other brands you may see on a quote
Other widely used brands are on the market too. According to the warranties the manufacturers publish, Sungrow offers 10 years; GoodWe offers 10 years, with an extended-warranty program for hybrid models running through 2026; and SMA offers 5–10 years depending on the model, with extensions available. What actually matters to you is the model you get, that model's warranty, and after-sales support in your area.
What to check on a quote
- The inverter's full model name, not just the brand — one brand makes on-grid, single-phase hybrid and three-phase models.
- The inverter size in kW, and how it relates to the total panel capacity.
- On-grid or hybrid. If hybrid, whether the batteries, backup accessories and backup sub-panel are included.
- The product warranty in years according to that model's documents, and whether any extension is included in the price.
- Surge protection on both the DC and AC sides.
- Which monitoring app is used, and who sets up the account for you.
- An inverter location out of direct sun and rain, with ventilation — and above flood level on flood-prone sites.
The brand and model actually used are named in every 19Energy quote before the job is agreed. If you have specific requirements — a brand with a longer standard warranty, say, or generator pairing — tell us when we first discuss the job. For choosing panels, see our solar panel brand comparison.
Sources used for this article
Figures in this article are based on public announcements and news reports (most sources are in Thai). If the conditions change, the latest official announcement from the relevant authority applies.
- HUAWEI SUN2000-KTL-L1 (single-phase) · HUAWEI
- HUAWEI SUN2000-KTL-M1 (three-phase) · HUAWEI
- Warranty terms and exclusions · Solis
- Solis S6-EH3P three-phase hybrid · Solis
- Solis S6-EH1P single-phase low-voltage hybrid manual · Solis (PDF)
- SolisCloud app · Solis
- Deye SUN-SG04LP1 hybrid inverter datasheet · Deye (PDF)
- Deye SUN-SG04LP3 three-phase hybrid manual · Deye (PDF)
- Deye Cloud app · App Store
Frequently asked questions
Which inverter brand is best?
No single brand is best for every job. Start with the type — on-grid or hybrid — and the number of phases matching your supply, then compare the model's warranty, the capabilities you need such as backup or generator pairing, and after-sales support.
Why is the Solis warranty only 5 years?
That's the standard term Solis publishes for its on-grid and hybrid inverters. It can be extended to 10, 15 or 20 years if requested within the first 5 years. If you choose Solis, decide on the extension at the outset.
Can an on-grid inverter be converted to hybrid later?
It means replacing the whole unit, or adding a separate battery system designed around the existing equipment. If you think you may want backup later, choosing a hybrid inverter from the start costs less.
Do I have to use the inverter brand's own app?
Yes, each brand has its own: HUAWEI uses FusionSolar, Solis uses SolisCloud and Deye uses Deye Cloud. All of them let you view your production history yourself.
Does the inverter warranty cover lightning or flood damage?
Generally not. Manufacturer warranties cover manufacturing defects. Damage from external events relies on your property insurance, and on protection built in at installation, such as surge protection and a suitable mounting position.
Related services and areas
Keep reading
- JA Solar, LONGi, Trina, Jinko, Canadian: How Do Solar Panel Brands Compare?What you can actually compare between panel brands is the price per watt and the number of years in the warranty document — this article puts both side by side for five brands.
- 7 Things to Check Before Choosing a Solar Installer in Southern ThailandThe cheapest price is not necessarily the best value, and the most expensive is not necessarily the best. Here is what to look at instead.
- On-Grid, Off-Grid or Hybrid Solar: What's the Difference and Which Suits You?The difference comes down to whether the system connects to the utility grid and whether it can store power — which changes both the price and the value.
- Single-Phase vs Three-Phase Power: Do You Need a New Meter for Solar?Your home's power supply sets how big a solar system you can install — and it's worth knowing early whether you need a new meter, which is a separate cost.