Foreword:
These two days of many people asked me, 'Our silicon production capacity has been so great, why big business is also crazy expansion? Can we even see overcapacity, those big business policy makers can not see?'
I have had similar doubts, and later found that: the expansion behind the new technology is the promotion of iteration!
New capacity, are the introduction of new technologies, cheaper prices, to produce better products, more competitive in the market.If they do not have the capacity to adopt new technologies, the old capacity of products without market competitiveness, It will be revolutionized by other enterprises; it is not as good as self-revolution in revolution of others.
Previously, we only heard of monocrystalline silicon and polycrystalline silicon; now there are a lot of new nouns emerging in the market: perc, half-chip, MBB, MWT, laminated tile, double-sided ...
In the wake of the tide of new technologies, production capacity of new technologies is a must, and I believe this is the fundamental reason why most companies expand their production capacity.So, as a high-tech industry with such an iterative technology, PV manufacturing industry must Maintain a high profit margin, otherwise there will be no funds to support such rapid technological innovation.
First, different technology lines of the mainstream power and capacity
Several technologies that have matured or are about to mature in 2017 are Perc Technology, Half-Chip Technology and MBB Multi-Gate Technology in 2017. In theory, these technologies are all compatible technologies that can be used in single crystal silicon On-chip, can also be used in polycrystalline silicon, but the superposition effect is different.
Traditional ordinary polycrystalline components power of 270W, ordinary single-crystal components power of 285W, the power difference of 15W; when a series of new superposition of their own technology, the power difference will be further widened. 2018 various technical routes of component power distribution as shown 1 shown.
1) additive black silicon
The current polycrystalline diamond application, the main use of additive technology to solve the problem of excessive reflectivity, so the main power of polycrystalline components shipped next year are 270 ~ 275W between the products, the production capacity can be as high as 40GW.
2) wet black silicon
Dry black silicon technology route reserve for a long time, but the cost can not come (cost per unit> 0.3 yuan), dry black silicon technology route is likely to face the fate of the elimination; GCL-Poly, the main push wet black silicon technology with a new generation The introduction of TS + black silicon technology, the cost dropped dramatically at the same time performance has improved, the mainstream power should be 275 W. This year, the expansion of black silicon equipment is very fast, black silicon equipment manufacturers have exceeded 200 units, corresponding to the total capacity of more than 16GW.
3) Ordinary single crystal components
Ordinary single crystal components power up to 285W, capacity will reach 30GW.
4) Perc battery technology
Perc battery technology is a compatibility technology that can be used in both polycrystalline silicon and monocrystalline silicon. Perc universal cell power is generally increased by about 20W; while polycrystalline silicon with Perc can only be upgraded 15W or so, and there is still no problem of attenuation is not effectively resolved, so the new Perc battery production capacity obviously favor the choice of monocrystalline silicon.
In 2018, single crystal perc module production capacity will reach 30GW; with black silicon technology processing polycrystalline perc module production capacity will reach 5GW.
5) N-type components
The technology and industrialization of N-type modules have also been greatly improved in 2017. 'N-type + pert + half-chip' enables the module power to reach 320W and the production capacity is estimated to be 2 ~ 3GW by 2018; 'N + Make the module power reach above 330W, the production capacity in 2018 is expected to be within 1GW;
6) Summary
Through the above analysis, we can see that the technologies such as half-chip, Perc, multi-main gate and the like are superposed on the monocrystalline silicon wafer to bring a more obvious improvement.When a series of new technologies are superposed, the power of the polycrystalline component can be 300W, Crystal module power will reach 330W, after superimposing a series of new technologies, the power difference between polycrystalline modules will be widened to 30W.
The production capacity of monocrystalline wafers will reach 38GW by the end of the Chinese New Year of 2017. The technologies such as half-wafer and MBB multi-gate have just become popular, and the production capacity is far less than that of monocrystalline wafers.
In view of the new technology superposition effect is better, as long as single and polycrystalline silicon can maintain a reasonable spread, with the latest and most advanced Perc, half-chip, multi-main grid capacity manufacturers will prefer single-crystal silicon.The 300W polycrystalline silicon black Perc + Multi-gate components may only exist in the theory, in reality there will be no manufacturers to a series of advanced production capacity superimposed on the poor performance of polycrystalline silicon.
Second, the new technology can reduce the crack generated
Cracked reason is produced because:
1) Uneven external force exerted on the components during production, transportation, installation, cleaning, hail reduction and so on.
2) PV glass on the front of the module and the back of the back panel are made of different materials with different temperature coefficients, so different stresses are generated on the front and back of the solar cell during thermal expansion and contraction.
3) The front of the cell silver solder paste at the working temperature is low, the temperature of the cell itself lead to cracked.
Monocrystals tend to produce continuous, through-type cracks along certain specific directions due to the same internal lattice sequence. Compared with polycrystalline components, single crystal components have a higher probability of being cracked during production, transportation and installation .
Several new technologies are applied to the monocrystalline silicon chip will help solve the problem of cracking.
1) Half-chip technology
Half-chip technology is to cut the cell to a cell in two and then encapsulated technology.The original 60 components are actually encapsulated 120 'half cell' cell because of the small area of a single cell Half, monocrystalline silicon easy to produce through the scope of the crack also corresponds to reduce the deformation caused by the module for a single sheet of cumulative deformation will be reduced.According to the disclosure of crystal Australia, monocrystalline half-piece components Under the same intensity of destructive force, less than 15% of the hidden cracks of conventional components.
2) double glass technology
Double-glass technology is the front and back glass packaging components are used package technology, because the front and back are made of glass, the temperature changes caused by thermal expansion and contraction changes consistent with the battery pack is encapsulated in front and back of the same stress can be effective Reduce the temperature change caused by the crack.
3) MBB multi-main gate technology
Conventional cells now use 4 to 5 main gate technology, and multi-main gate technology enables the number of single cells on the main gate to reach 12; corresponding to a single main gate width of only one-third of the conventional battery First, the gate line shielding will not make the temperature of the back of the gate line is significantly lower.Cell more balanced temperature to reduce the occurrence of crack.In addition, the multi-gate technology is conducive to the current collecting cells, so even if the nuances However, with the help of multi-main-gate technology, the MBB multi-gate technology will not reduce the probability of cracking and improve the tolerance of the solar cell to the crack.
