What are the advantages of the n-type cell?

Improved efficiency 

N-type cells are simply more efficient, i.e. more power is achieved with the same surface area, thus more energy over time. This is one of the main advantages, since the market is always demanding more power. In recent years this increase in power was achieved mainly by increasing the collector surface area, i.e. by using cells with a larger surface area and/or simply using more cells per panel. But this increase in surface area results in larger and larger, heavier and heavier modules that are less and less easy to handle. Several voices in the industry are of the opinion that we have already reached maximum module sizes, and that we should not go any larger. Therefore, the only way to achieve more power is to achieve higher efficiency. And the n-type cell is one of the best allies in this challenge to achieve more power without increasing the module surface area. Now is perhaps the time when we will really see new increases in module efficiency. 

No LID 

In n-type cells, as mentioned above, phosphorus is often used for cell doping. Since boron is not used, there is no possible combination between boron and oxygen that may be present in the cell. This boron-oxygen combination is largely responsible for the loss of power due to the LID (Light Induced Degradation) effect. This LID effect present in p-type modules using boron, as doping causes yield losses between 1% and 3% of normal, and sometimes much more, from early in the life of the installation, i.e. in its first exposures to the sun. These losses are irreversible, that is, for the entire life of the PV module. This is no small feat when you take into account all the energy that this represents over the lifetime of a PV installation, which should reach more than 35 years in operation. (Some manufacturers use gallium instead of boron in their p-type cells, thus avoiding the boron-oxygen effect, having more power available, and generating more energy over the lifetime, e.g. Longi for years, JA Solar and REC in their respective new module lines). 

Less PID 

Speaking of degradation, this time potential induced, the n-type also has a higher resistance to PID (Potential Induced Degradation). 

PID with p-type cells comes mainly with the effect of glass imperfections, such as oxygen, which combines with boron. Whereas, in n-type modules, the quality of the cell itself can cause PID losses, and by not having boron, much of the problem is eliminated. 

These two advantages, no LID and less PID, are summarized for the end customer in less degradation in the first year, and also in less degradation in subsequent years. In other words, more energy over the lifetime of the installation. 

But it doesn't end there! 

Better temperature coefficient 

The n-type cells have a better temperature coefficient than p-type cells. This means that power loss, mainly due to drops in voltage, is less affected when temperatures rise. This allows higher power output in conditions difficult for silicon, such as when it is hotter, which is generally when there is also more sunlight. So we can say that n-type cells offer more power when conditions are more adverse and interesting. 

Much higher Bifaciality Coefficient 

Since nothing happens by chance, we also discuss bifacial modules here. As we already know, this technology is increasingly gaining a foothold on the market and is even driving and leading the research and development of PV modules in general. Why is that? Since PERC technology arrived on a massive scale, bifacial technology is making great strides, because only one small step between the two can have large repercussions.

The bifacial technology has captured a large part of the market, mainly in large plants, due to its more than interesting increase in production, while also having a reduced €/Wp price increase. In other words, by paying just a little more, you can generate much more.

The n-type cell has a better bifaciality coefficient than the p-type cell. In other words, this cell can generate more power from the rear side than the p-type cell. The bifaciality factor or coefficient (%) is defined as the ratio between the efficiency obtained from the rear side of the module and the efficiency obtained from the front side of the module when both sides are subjected to the same irradiance, for example, 1000W per square meter as in the standard tests. 

This advantage is not negligible, especially when some manufacturers are evaluating the possibility of maintaining only bifacial module lines in the not so distant future.