---
title: "Hyundai HiS-T635NJ vs Hyundai HIE-S390VG - Solar Panel Comparison | ComparePV"
description: "Compare Hyundai HiS-T635NJ vs Hyundai HIE-S390VG side by side: what actually differs, output when it is hot, thirty-year production, and the full specification."
source: "https://comparepv.com/compare/hd-hyundai-energy-solutions-his-t635nj/hyundai-hie-s390vg"
image: "https://comparepv.com/og/compare/panels/hd-hyundai-energy-solutions-his-t635nj/hyundai-hie-s390vg.png"
updated: 2026-09-11
---

# Hyundai HiS-T635NJ vs Hyundai HIE-S390VG

HiS-T635NJ leads on the differences that matter

The largest is module efficiency: 2.82 pp more efficient. 2 of 18 comparable parameters are identical, with 1 more left out because at least one datasheet does not publish it.


## The two panels


| Attribute | A | B |
| --- | --- | --- |
| Panel | [Hyundai HiS-T635NJ](https://comparepv.com/panel/hd-hyundai-energy-solutions-his-t635nj) | [Hyundai HIE-S390VG](https://comparepv.com/panel/hyundai-hie-s390vg) |
| Manufacturer | Hyundai | Hyundai |
| Power | 635 Wp | 390 Wp |
| Efficiency | 22.72 % | 19.90 % |
| Technology | TOPCon | PERC |


## Where they differ

Ranked by how much the difference matters, not by datasheet order.


| Parameter | HiS-T635NJ | HIE-S390VG | Difference |
| --- | --- | --- | --- |
| Module efficiency | 22.72 % | 19.90 % | +2.82 pp for HiS-T635NJ |
| Temperature coefficient | -0.290 %/°C | -0.340 %/°C | +0.050 %/°C for HiS-T635NJ |
| Rated power | 635 Wp | 390 Wp | +245 W for HiS-T635NJ |
| Power density | 227.2 Wp/m² | 199.0 Wp/m² | +28.2 Wp/m² for HiS-T635NJ |
| Performance warranty | 30 yrs | 25 yrs | +5 yrs for HiS-T635NJ |
| Annual degradation | 0.40 %/yr | 0.55 %/yr | -0.15 %/yr for HiS-T635NJ |
| Weight | 34.7 kg | 22.0 kg | -12.7 kg for HIE-S390VG |
| Product warranty | 12 yrs | 25 yrs | +13 yrs for HIE-S390VG |
| Open-circuit voltage | 57.56 V | 46.30 V | 11.26 V apart |
| Short-circuit current | 13.98 A | 10.87 A | 3.11 A apart |
| Module area | 2.795 m² | 1.960 m² | 0.836 m² apart |
| Cell technology | TOPCon | PERC | TOPCon vs PERC |
| Voltage at max power | 47.57 V | 38.50 V | 9.07 V apart |
| Current at max power | 13.35 A | 10.13 A | 3.22 A apart |
| Bifacial | Yes | No | Yes vs No |
| Dimensions | 2465x1134x30 mm | 1719x1140x35 mm | 2465x1134x30 mm vs 1719x1140x35 mm |


## Every compared parameter


| Parameter | HiS-T635NJ | HIE-S390VG |
| --- | --- | --- |
| Rated power | 635 Wp | 390 Wp |
| Module efficiency | 22.72 % | 19.90 % |
| Power density | 227.2 Wp/m² | 199.0 Wp/m² |
| Open-circuit voltage | 57.56 V | 46.30 V |
| Voltage at max power | 47.57 V | 38.50 V |
| Short-circuit current | 13.98 A | 10.87 A |
| Current at max power | 13.35 A | 10.13 A |
| Temperature coefficient | -0.290 %/°C | -0.340 %/°C |
| Dimensions | 2465x1134x30 mm | 1719x1140x35 mm |
| Module area | 2.795 m² | 1.960 m² |
| Weight | 34.7 kg | 22.0 kg |
| Weight per kWp | 54.6 kg/kWp | 56.4 kg/kWp |
| Product warranty | 12 yrs | 25 yrs |
| Performance warranty | 30 yrs | 25 yrs |
| Annual degradation | 0.40 %/yr | 0.55 %/yr |
| Cell technology | TOPCon | PERC |
| Cell type | Monocrystalline | Monocrystalline |
| Cell count | 156 | - |
| Bifacial | Yes | No |


## Thirty-year yield

Each panel's own declared degradation curve, at 1,200 kWh/kWp a year

- **Cumulative output, HiS-T635NJ:** 21,306 kWh
- **Cumulative output, HIE-S390VG:** 12,640 kWh
- **Gap:** 8,666 kWh


## Output when hot


| Condition | Cell temperature | HiS-T635NJ | HIE-S390VG | Retained |
| --- | --- | --- | --- | --- |
| Standard test conditions | 25 °C | 635 W | 390 W | 100.0% of rated power |
| Cool, bright day | 40 °C | 607 W | 370 W | 94.9% of rated power |
| Typical summer roof | 55 °C | 580 W | 350 W | 89.8% of rated power |
| Hot roof | 70 °C | 552 W | 330 W | 84.7% of rated power |


## Against the whole database


| Measure | HiS-T635NJ | HIE-S390VG | Out of | Note |
| --- | --- | --- | --- | --- |
| Efficiency | #3,302 | #12,416 | 14,129 | HiS-T635NJ leads by 9,114 places |
| Power density | #3,309 | #12,416 | 14,129 | HiS-T635NJ leads by 9,107 places |
| Heat behaviour | #2,220 | #8,846 | 14,129 | HiS-T635NJ leads by 6,626 places |
| Weight | #9,102 | #10,727 | 14,129 | HiS-T635NJ leads by 1,625 places |
| Warranty | #21 | #9,912 | 14,129 | HiS-T635NJ leads by 9,891 places |
| Overall | #2,387 | #11,364 | 14,129 | HiS-T635NJ leads by 8,977 places |


## Questions


### Which panel is better: Hyundai HiS-T635NJ or Hyundai HIE-S390VG?

According to our database: **Hyundai HiS-T635NJ** has higher module efficiency (**22.72%** vs **19.90%**); **Hyundai HiS-T635NJ** tolerates heat better (temp coeff **-0.290%/°C** vs **-0.340%/°C**). See the full spec comparison and 30-year energy simulation above for a complete picture.


### What is the efficiency of Hyundai HiS-T635NJ and Hyundai HIE-S390VG?

**Hyundai HiS-T635NJ** has a module efficiency of **22.72%**, while **Hyundai HIE-S390VG** is **19.90%**. Higher efficiency means more electricity from the same roof area - useful when space is limited.


### What cell technology does Hyundai HiS-T635NJ use vs Hyundai HIE-S390VG?

**Hyundai HiS-T635NJ** uses **TOPCon** cells; **Hyundai HIE-S390VG** uses **PERC**. Modern **n-type** technologies (**TOPCon**, **HJT**, BC) typically deliver higher efficiency and lower degradation compared to older **PERC** (p-type) cells.


### What is the warranty on Hyundai HiS-T635NJ and Hyundai HIE-S390VG?

**Hyundai HiS-T635NJ** has a **30 years** power warranty; **Hyundai HIE-S390VG** has a **25 years** power warranty. The power warranty guarantees a minimum percentage of rated output at the end of the warranty period (typically 80**-87%**). Product (materials) warranties are usually shorter.


### Are Hyundai HiS-T635NJ and Hyundai HIE-S390VG bifacial panels?

**Hyundai HiS-T635NJ** is bifacial (captures light from both faces); **Hyundai HIE-S390VG** is monofacial. Bifacial panels work best on ground mounts or raised structures with a light-coloured surface underneath.


## Related comparisons

- [Hyundai HiS-T635NJ vs Hyundai HiS-T640NJ](https://comparepv.com/compare/hd-hyundai-energy-solutions-his-t635nj/hd-hyundai-energy-solutions-his-t640nj) - The same specification on paper
- [Hyundai HiS-T635NJ vs Hyundai HiS-T630NJ](https://comparepv.com/compare/hd-hyundai-energy-solutions-his-t635nj/hd-hyundai-energy-solutions-his-t630nj) - The same specification on paper
- [Hyundai HIE-S390VG vs Hyundai HIE-S410VG](https://comparepv.com/compare/hyundai-hie-s390vg/hyundai-hie-s410vg) - 4 differences, the largest is module efficiency
- [Hyundai HIE-S390VG vs Hyundai HIE-S405VG](https://comparepv.com/compare/hyundai-hie-s390vg/hyundai-hie-s405vg) - 4 differences, the largest is module efficiency
- [Hyundai HIE-S390VG vs Hyundai HIE-S400VG](https://comparepv.com/compare/hyundai-hie-s390vg/hyundai-hie-s400vg) - 3 differences, the largest is module efficiency
- [Hyundai HIE-S390VG vs Hyundai HIE-S395VG](https://comparepv.com/compare/hyundai-hie-s390vg/hyundai-hie-s395vg) - One difference: module efficiency


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Source: https://comparepv.com/compare/hd-hyundai-energy-solutions-his-t635nj/hyundai-hie-s390vg

Not in this file, on the page: the thirty-year yield curve year by year at a cell temperature you pick and a written summary generated on request.