As we all know, in the whole life cycle, the processing technology of aluminum is only electrolytic aluminum as a high energy consumption link, but considering the recycling characteristics of aluminum, the energy consumption and carbon emissions of recycled aluminum are only 3%~8% of that of primary aluminum. Much smaller than recycled steel processing.

Recycled aluminum only needs to melt scrap aluminum to remove impurities and add alloying elements, so the carbon emission is much lower than that of primary aluminum, but the electric furnace, rolling and other processes during steel recycling have a large amount of power consumption and carbon emissions.

With the vigorous development of the photovoltaic industry and the increase in installed capacity year by year and the expiration of the life of old modules, the number of decommissioned photovoltaic modules and their waste has gradually increased. As the world's largest photovoltaic country, China's photovoltaic waste problem has become increasingly apparent. The report of the International Renewable Energy Agency and the International Energy Agency's photovoltaic system project also proposes that by 2050, the total cumulative installed photovoltaic capacity in the world will reach 4.5TW, and only the retired components in the Chinese market can reach 20Mt (megatons). In the context of the upcoming wave of component recycling, we should not be short-sighted and only focus on current costs and investments. As the main force of the dual carbon goal, we should evaluate its carbon emissions from the full life cycle.

1) Analysis of the recovery rate of aluminum alloy frame and steel frame

Due to the corrosion-resistant properties of aluminum alloys, it is close to infinite recycling and only consumes very little. According to the International Aluminium Institute, 75% of the 1.5 billion tonnes of aluminium ever produced globally is still in use. Due to its corrosiveness, the recovery rate of steel has been maintained at the level of 55-65%, which cannot be effectively improved.

2) Analysis of energy consumption for recycling aluminum alloy frame and steel frame

In the context of "dual carbon", aluminum alloys also have lower recycling energy consumption and recycling carbon emissions during the recycling process. Compared with recycled steel, the carbon emission of recycled aluminum is 0.23t, which is only 22.3% of recycled steel.

3) Calculation of carbon emission factors for the whole life cycle of aluminum alloy frame and steel frame

In order to more accurately evaluate the carbon emission reduction capabilities of aluminum alloy frames and steel frames, the carbon emission factors of aluminum alloy and steel frames in the whole life cycle were calculated by searching a large number of literatures. The calculation results found that the aluminum alloy frame has a lower carbon emission factor. In order to more intuitively show its carbon emission impact, taking 1GW modules as an example, the carbon emission data of the aluminum frame and steel frame of the power station are converted, and it is found that the carbon emission factor of the aluminum alloy frame is only 52.35% of that of the steel frame in the whole life cycle, and the carbon emission is higher. Low.

4) Other carbon emission factors

The density of the steel frame is higher, the components are heavier, and the carbon emissions during transportation, handling, and installation increase accordingly. Here, we take the calculation of transportation carbon emissions as an example.