Half-cut solar cells: What you need to know

Solar technology is improving across all facets of the typical solar installation. In this article, we'll discuss half-cut solar cells, a variation of standard silicon solar cells that can help improve solar panel performance.

Just as bifacial solar panels and PERC solar cells provide small boosts in the efficiencies of silicon solar panels, implementing half-cut cells in solar panels can help improve the power output of a solar panel system. Half-cut solar cells are exactly what their name suggests - they are traditional silicon solar cells that have been cut in half using a laser cutter.

Half-cut cells provide several benefits over traditional solar cells. Most importantly, half-cut solar cells offer improved performance and durability. Performance-wise, half-cut cells can increase panel efficiencies by a few percentage points. And in addition to better production numbers, half-cut cells are more physically durable than their traditional counterparts; because they are smaller in size, they're more resistant to cracking.

Due to these advantages, solar panels built with half-cut solar cells have the potential to provide quicker solar payback periods for property owners installing solar energy systems. Especially for installations where shading and limited space are constraining factors, half-cut cells can make a solar panel installation even more worth the upfront cost.

There are a few main ways that half-cut cells can boost solar panel output and performance:

1. Reduced resistive losses

One source of power loss when solar cells convert sunlight into electricity, is resistive losses, or power lost during electrical current transport. Solar cells transport current using the thin metal ribbons that cross their surface and connect them to neighboring wires and cells, and moving current through these ribbons leads to some energy loss. By cutting solar cells in half, the current generated from each cell is halved, and lower current flowing leads to lower resistive losses as electricity moves throughout cells and wires in a solar panel.

2. Higher shade tolerance

Half-cut cells are more resistant to the effects of shade than traditional solar cells. This is not due to the cells being cut in half but rather a result of the wiring methods used to connect half-cut cells in a panel. In traditional solar panels built with full cells, the cells are wired together in rows, known as series wiring. In series wiring schemes, if one cell in a row is shaded and not producing energy, the entire row of cells will stop producing power. Standard panels typically have three separate rows of cells wired together, so shade on one cell of one row would eliminate a third of that panel's power production.

Wiring scheme for a standard solar panel. There are three separate "rows" of cells wired together in parallel. Source: www.solarquotes.com.au

Half-cut cells are also wired in series, but because panels made with half-cut cells have double the number of cells (120 instead of 60), there are also double the number of separate rows of cells. This type of wiring allows panels built with half-cut cells to lose less power when a single cell is shaded because a single-shaded cell can only eliminate a sixth of the total panel power output.

Wiring scheme for a solar panel made with half-cut cells. There are six separate "rows" of cells wired together in parallel. Source: www.solarquotes.com.au

The first half-cut cell solar panels were introduced in 2014 by REC Solar, and they have since been transferring much of their module manufacturing to be equipped for half-cut cell production. Aside from REC, many manufacturers have introduced half-cell modules. Trina Solar, Hanwha Q CELLS, JinkoSolar, and LONGi Solar are just some of the large solar panel manufacturers that produce half-cell panel options.

Solar manufacturers can transition to half-cell production

Half-cut cell production lines are not much different from traditional solar cell lines, and any panel manufacturer looking to begin making half-cut cells doesn't need to completely overhaul existing factories or production processes. There are two additional steps needed when making half-cut cells: a cell-cutting step and a stringing step.

Cell cutting is done with a laser and involves splitting standard solar cells into two halves. Solar cells can be very fragile, and laser cutting allows for precise lines to be cut into solar cells.

As with cell cutting, the stringing process needed when making half-cut cells is a very precise task. Stringing is the process of placing the conductive strips, known as busbars, on each half-cut cell. Due to the smaller size of half-cut cells, the busbars used are smaller and require specialized equipment to accurately place them.

Half-cut solar cells are an exciting technology in the solar industry and can be a solution for property owners looking to maximize energy production with high-efficiency, shade-tolerant solar panels. In order to find the best solar system option for you at the right price, register your property on the EnergySage Solar Marketplace to begin receiving custom solar quotes submitted by local solar companies. If you are interested in solar panels made with half-cut solar cells, you can simply leave a note on your profile for installers to see. Not all solar panel manufacturers use half-cut cell technology, but certain installers may carry half-cut panels.