--- title: "AIKO AIKO-A770-GRH78Dw vs AIKO AIKO-A780-GRH78Dw - Solar Panel Comparison | ComparePV" description: "Compare AIKO AIKO-A770-GRH78Dw vs AIKO AIKO-A780-GRH78Dw 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-a770-grh78dw/aiko-aiko-a780-grh78dw" updated: 2026-09-11 --- # AIKO AIKO-A770-GRH78Dw vs AIKO AIKO-A780-GRH78Dw A780-GRH78Dw leads on the differences that matter The largest is module efficiency: 0.30 pp more efficient. 15 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-A770-GRH78Dw](https://comparepv.com/panel/aiko-aiko-a770-grh78dw) | [AIKO AIKO-A780-GRH78Dw](https://comparepv.com/panel/aiko-aiko-a780-grh78dw) | | Manufacturer | AIKO | AIKO | | Power | 770 Wp | 780 Wp | | Efficiency | 24.00 % | 24.30 % | | Technology | Back Contact | Back Contact | ## Where they differ Ranked by how much the difference matters, not by datasheet order. | Parameter | A770-GRH78Dw | A780-GRH78Dw | Difference | | --- | --- | --- | --- | | Module efficiency | 24.00 % | 24.30 % | +0.30 pp for A780-GRH78Dw | | Power density | 239.7 Wp/m² | 242.8 Wp/m² | +3.1 Wp/m² for A780-GRH78Dw | | Rated power | 770 Wp | 780 Wp | +10 W for A780-GRH78Dw | ## Every compared parameter | Parameter | A770-GRH78Dw | A780-GRH78Dw | | --- | --- | --- | | Rated power | 770 Wp | 780 Wp | | Module efficiency | 24.00 % | 24.30 % | | Power density | 239.7 Wp/m² | 242.8 Wp/m² | | Open-circuit voltage | 58.72 V | 58.92 V | | Voltage at max power | 48.77 V | 48.97 V | | Short-circuit current | 16.64 A | 16.78 A | | Current at max power | 15.79 A | 15.93 A | | Temperature coefficient | -0.260 %/°C | -0.260 %/°C | | Dimensions | 2465x1303x33 mm | 2465x1303x33 mm | | Module area | 3.212 m² | 3.212 m² | | Weight | 39.8 kg | 39.8 kg | | Weight per kWp | 51.7 kg/kWp | 51.0 kg/kWp | | Product warranty | 15 yrs | 15 yrs | | Performance warranty | 30 yrs | 30 yrs | | Annual degradation | - | - | | Cell technology | Back Contact | Back Contact | | Cell type | Monocrystalline | Monocrystalline | | Cell count | 156 | 156 | | 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 Same temp coeff. for both panels (-0.260 %/°C), so a warmer roof scales both curves by the same factor: the totals fall together and neither panel gains on the other. - **Cumulative output, A770-GRH78Dw:** 25,835 kWh - **Cumulative output, A780-GRH78Dw:** 26,171 kWh - **Gap:** 336 kWh ## Output when hot | Condition | Cell temperature | A770-GRH78Dw | A780-GRH78Dw | Retained | | --- | --- | --- | --- | --- | | Standard test conditions | 25 °C | 770 W | 780 W | 100.0% of rated power | | Cool, bright day | 40 °C | 740 W | 750 W | 96.1% of rated power | | Typical summer roof | 55 °C | 710 W | 719 W | 92.2% of rated power | | Hot roof | 70 °C | 680 W | 689 W | 88.3% of rated power | ## Against the whole database | Measure | A770-GRH78Dw | A780-GRH78Dw | Out of | Note | | --- | --- | --- | --- | --- | | Efficiency | #303 | #131 | 14,005 | A780-GRH78Dw leads by 172 places | | Power density | #347 | #138 | 14,005 | A780-GRH78Dw leads by 209 places | | Heat behaviour | #511 | #511 | 14,005 | Tied - the same position in the database | | Weight | #5,072 | #4,377 | 14,005 | A780-GRH78Dw leads by 695 places | | Warranty | #21 | #21 | 14,005 | Tied - the same position in the database | | Overall | #40 | #16 | 14,005 | A780-GRH78Dw leads by 24 places | ## Questions ### Which panel is better: AIKO AIKO-A770-GRH78Dw or AIKO AIKO-A780-GRH78Dw? According to our database: **AIKO AIKO-A780-GRH78Dw** has higher module efficiency (**24.30%** vs **24.00%**). See the full spec comparison and 30-year energy simulation above for a complete picture. ### What is the efficiency of AIKO AIKO-A770-GRH78Dw and AIKO AIKO-A780-GRH78Dw? **AIKO AIKO-A770-GRH78Dw** has a module efficiency of **24.00%**, while **AIKO AIKO-A780-GRH78Dw** is **24.30%**. Higher efficiency means more electricity from the same roof area - useful when space is limited. ### What cell technology does AIKO AIKO-A770-GRH78Dw use vs AIKO AIKO-A780-GRH78Dw? **AIKO AIKO-A770-GRH78Dw** uses **Back Contact** cells; **AIKO AIKO-A780-GRH78Dw** uses **Back Contact**. 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-A770-GRH78Dw and AIKO AIKO-A780-GRH78Dw? **AIKO AIKO-A770-GRH78Dw** has a **30 years** power warranty; **AIKO AIKO-A780-GRH78Dw** 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-A770-GRH78Dw and AIKO AIKO-A780-GRH78Dw bifacial panels? Both **AIKO AIKO-A770-GRH78Dw** and **AIKO AIKO-A780-GRH78Dw** 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-A770-GRH78Dw vs AIKO AIKO-A805-GRH78Dw](https://comparepv.com/compare/aiko-aiko-a770-grh78dw/aiko-aiko-a805-grh78dw) - 4 differences, the largest is module efficiency - [AIKO AIKO-A770-GRH78Dw vs AIKO AIKO-A800-GRH78Dw](https://comparepv.com/compare/aiko-aiko-a770-grh78dw/aiko-aiko-a800-grh78dw) - 3 differences, the largest is module efficiency - [AIKO AIKO-A770-GRH78Dw vs AIKO AIKO-A795-GRH78Dw](https://comparepv.com/compare/aiko-aiko-a770-grh78dw/aiko-aiko-a795-grh78dw) - 3 differences, the largest is module efficiency - [AIKO AIKO-A770-GRH78Dw vs AIKO AIKO-A790-GRH78Dw](https://comparepv.com/compare/aiko-aiko-a770-grh78dw/aiko-aiko-a790-grh78dw) - 3 differences, the largest is module efficiency - [AIKO AIKO-A770-GRH78Dw vs AIKO AIKO-A785-GRH78Dw](https://comparepv.com/compare/aiko-aiko-a770-grh78dw/aiko-aiko-a785-grh78dw) - 3 differences, the largest is module efficiency - [AIKO AIKO-A770-GRH78Dw vs AIKO AIKO-A775-GRH78Dw](https://comparepv.com/compare/aiko-aiko-a770-grh78dw/aiko-aiko-a775-grh78dw) - The same specification on paper --- Source: https://comparepv.com/compare/aiko-aiko-a770-grh78dw/aiko-aiko-a780-grh78dw 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.