---
title: "AIKO AIKO-A785-GRH78Dw vs Tongwei TWMNF-66HD - Solar Panel Comparison | ComparePV"
description: "Compare AIKO AIKO-A785-GRH78Dw vs Tongwei TWMNF-66HD side by side: what actually differs, output when it is hot, thirty-year production, and the full specification."
source: "https://comparepv.com/compare/aiko-aiko-a785-grh78dw/tongwei-twmnf-66hd"
updated: 2026-09-11
---

# AIKO AIKO-A785-GRH78Dw vs Tongwei TWMNF-66HD

AIKO-A785-GRH78Dw leads on the differences that matter

The largest is module efficiency: 1.40 pp more efficient. 4 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 | [AIKO AIKO-A785-GRH78Dw](https://comparepv.com/panel/aiko-aiko-a785-grh78dw) | [Tongwei TWMNF-66HD](https://comparepv.com/panel/tongwei-twmnf-66hd) |
| Manufacturer | AIKO | Tongwei |
| Power | 785 Wp | 715 Wp |
| Efficiency | 24.40 % | 23.00 % |
| Technology | Back Contact | TOPCon |


## Where they differ

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


| Parameter | AIKO-A785-GRH78Dw | TWMNF-66HD | Difference |
| --- | --- | --- | --- |
| Module efficiency | 24.40 % | 23.00 % | +1.40 pp for AIKO-A785-GRH78Dw |
| Rated power | 785 Wp | 715 Wp | +70 W for AIKO-A785-GRH78Dw |
| Power density | 244.4 Wp/m² | 230.2 Wp/m² | +14.2 Wp/m² for AIKO-A785-GRH78Dw |
| Temperature coefficient | -0.260 %/°C | -0.280 %/°C | +0.020 %/°C for AIKO-A785-GRH78Dw |
| Open-circuit voltage | 59.02 V | 49.11 V | 9.91 V apart |
| Module area | 3.212 m² | 3.106 m² | 0.106 m² apart |
| Short-circuit current | 16.85 A | 18.50 A | 1.65 A apart |
| Weight | 39.8 kg | 37.9 kg | -1.9 kg for TWMNF-66HD |
| Cell technology | Back Contact | TOPCon | Back Contact vs TOPCon |
| Voltage at max power | 49.07 V | 40.86 V | 8.21 V apart |
| Cell count | 156 | 132 | 24 cells apart |
| Weight per kWp | 50.7 kg/kWp | 53.0 kg/kWp | -2.3 kg/kWp for AIKO-A785-GRH78Dw |
| Current at max power | 16.00 A | 17.50 A | 1.50 A apart |
| Dimensions | 2465x1303x33 mm | 2384x1303x33 mm | 2465x1303x33 mm vs 2384x1303x33 mm |


## Every compared parameter


| Parameter | AIKO-A785-GRH78Dw | TWMNF-66HD |
| --- | --- | --- |
| Rated power | 785 Wp | 715 Wp |
| Module efficiency | 24.40 % | 23.00 % |
| Power density | 244.4 Wp/m² | 230.2 Wp/m² |
| Open-circuit voltage | 59.02 V | 49.11 V |
| Voltage at max power | 49.07 V | 40.86 V |
| Short-circuit current | 16.85 A | 18.50 A |
| Current at max power | 16.00 A | 17.50 A |
| Temperature coefficient | -0.260 %/°C | -0.280 %/°C |
| Dimensions | 2465x1303x33 mm | 2384x1303x33 mm |
| Module area | 3.212 m² | 3.106 m² |
| Weight | 39.8 kg | 37.9 kg |
| Weight per kWp | 50.7 kg/kWp | 53.0 kg/kWp |
| Product warranty | 15 yrs | 15 yrs |
| Performance warranty | 30 yrs | 30 yrs |
| Annual degradation | - | - |
| Cell technology | Back Contact | TOPCon |
| Cell type | Monocrystalline | Monocrystalline |
| Cell count | 156 | 132 |
| Bifacial | Yes | Yes |


## Thirty-year yield

A 1.0% first-year loss then 0.40% a year, assumed for both panels, at 1,200 kWh/kWp a year

- **Cumulative output, AIKO-A785-GRH78Dw:** 26,338 kWh
- **Cumulative output, TWMNF-66HD:** 23,990 kWh
- **Gap:** 2,348 kWh


## Output when hot


| Condition | Cell temperature | AIKO-A785-GRH78Dw | TWMNF-66HD | Retained |
| --- | --- | --- | --- | --- |
| Standard test conditions | 25 °C | 785 W | 715 W | 100.0% of rated power |
| Cool, bright day | 40 °C | 754 W | 685 W | 95.8% of rated power |
| Typical summer roof | 55 °C | 724 W | 655 W | 91.6% of rated power |
| Hot roof | 70 °C | 693 W | 625 W | 87.4% of rated power |


## Against the whole database


| Measure | AIKO-A785-GRH78Dw | TWMNF-66HD | Out of | Note |
| --- | --- | --- | --- | --- |
| Efficiency | #99 | #1,919 | 14,005 | AIKO-A785-GRH78Dw leads by 1,820 places |
| Power density | #87 | #2,018 | 14,005 | AIKO-A785-GRH78Dw leads by 1,931 places |
| Heat behaviour | #511 | #1,309 | 14,005 | AIKO-A785-GRH78Dw leads by 798 places |
| Weight | #4,120 | #6,744 | 14,005 | AIKO-A785-GRH78Dw leads by 2,624 places |
| Warranty | #21 | #21 | 14,005 | Tied - the same position in the database |
| Overall | #10 | #450 | 14,005 | AIKO-A785-GRH78Dw leads by 440 places |


## Questions


### Which panel is better: AIKO AIKO-A785-GRH78Dw or Tongwei TWMNF-66HD?

According to our database: **AIKO AIKO-A785-GRH78Dw** has higher module efficiency (**24.40%** vs **23.00%**); **AIKO AIKO-A785-GRH78Dw** tolerates heat better (temp coeff **-0.260%/°C** vs **-0.280%/°C**). See the full spec comparison and 30-year energy simulation above for a complete picture.


### What is the efficiency of AIKO AIKO-A785-GRH78Dw and Tongwei TWMNF-66HD?

**AIKO AIKO-A785-GRH78Dw** has a module efficiency of **24.40%**, while **Tongwei TWMNF-66HD** is **23.00%**. Higher efficiency means more electricity from the same roof area - useful when space is limited.


### What cell technology does AIKO AIKO-A785-GRH78Dw use vs Tongwei TWMNF-66HD?

**AIKO AIKO-A785-GRH78Dw** uses **Back Contact** cells; **Tongwei TWMNF-66HD** uses **TOPCon**. 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 AIKO AIKO-A785-GRH78Dw and Tongwei TWMNF-66HD?

**AIKO AIKO-A785-GRH78Dw** has a **30 years** power warranty; **Tongwei TWMNF-66HD** has a **30 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 AIKO AIKO-A785-GRH78Dw and Tongwei TWMNF-66HD bifacial panels?

Both **AIKO AIKO-A785-GRH78Dw** and **Tongwei TWMNF-66HD** are bifacial - they capture reflected light from the ground, which can add 5**-15%** more annual energy on ground-mount or elevated rooftop installations with a light surface beneath.


## Related comparisons

- [AIKO AIKO-A785-GRH78Dw vs AIKO AIKO-A805-GRH78Dw](https://comparepv.com/compare/aiko-aiko-a785-grh78dw/aiko-aiko-a805-grh78dw) - 3 differences, the largest is module efficiency
- [AIKO AIKO-A785-GRH78Dw vs AIKO AIKO-A800-GRH78Dw](https://comparepv.com/compare/aiko-aiko-a785-grh78dw/aiko-aiko-a800-grh78dw) - 3 differences, the largest is module efficiency
- [AIKO AIKO-A785-GRH78Dw vs AIKO AIKO-A795-GRH78Dw](https://comparepv.com/compare/aiko-aiko-a785-grh78dw/aiko-aiko-a795-grh78dw) - 3 differences, the largest is module efficiency
- [AIKO AIKO-A785-GRH78Dw vs AIKO AIKO-A790-GRH78Dw](https://comparepv.com/compare/aiko-aiko-a785-grh78dw/aiko-aiko-a790-grh78dw) - One difference: module efficiency
- [AIKO AIKO-A785-GRH78Dw vs AIKO AIKO-A780-GRH78Dw](https://comparepv.com/compare/aiko-aiko-a785-grh78dw/aiko-aiko-a780-grh78dw) - The same specification on paper
- [AIKO AIKO-A785-GRH78Dw vs AIKO AIKO-A775-GRH78Dw](https://comparepv.com/compare/aiko-aiko-a785-grh78dw/aiko-aiko-a775-grh78dw) - 3 differences, the largest is module efficiency


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Source: https://comparepv.com/compare/aiko-aiko-a785-grh78dw/tongwei-twmnf-66hd

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.

