What are bifacial solar panels?

Bifacial solar panels are a rapidly growing technology that has piqued the interest of many renewable energy enthusiasts. While traditional solar panels can only capture sunlight with one sky-facing layer, bifacial solar panels use both sides of the equipment to absorb more of the sun’s energy and produce larger amounts of emission-free electricity.

Bifacial solar panels are gaining a lot of momentum in the commercial and utility-scale renewable energy industries — this technolology made up roughly 9% of California’s nonresidential solar capacity in 2021. But this doesn’t mean the technology is going to completely replace traditional solar panels.

Key insights

• Bifacial solar panels can increase the total power output of a photovoltaic (PV) system.
• Two-sided solar power generation is easier to capture on a flat roof or with a ground-mounted array, making it less ideal for the typical homeowner.
• It's easier to recoup the higher cost of bifacial solar panels when used in large-scale facilities.

How do bifacial solar panels work?

Bifacial installations work by absorbing sunlight on both the top and bottom of a set of solar panels. Bifacial solar collectors get their name from the two different “faces” of the panels where sunlight can be captured.

Bifacial solar panels can generate up to 27% more solar power than monofacial panels due to their double-sided energy absorption abilities.

Bifacial arrays are installed at an angle to receive as much direct sunlight as possible on one side of the equipment. The second face points to the ground and lets the panel absorb any diffused sunlight that has reflected off the ground.

To increase their power generation potential, bifacial arrays must be installed with a minimal number of structural components beneath the panels that could potentially block any sunlight from reaching the back of the solar collectors.

For the highest possible energy yields, bifacial panels can also be installed on highly reflective surfaces, such as white sand or concrete, to absorb the maximum amount of diffused sunlight.

Bifacial vs. monofacial solar panels

Both bifacial and monofacial (also known as traditional or single-side) solar panels work by generating electricity within many individual photovoltaic (PV) cells. While monofacial panels only absorb sunlight from their top surface, the PV cells in traditional arrays are encapsulated above a “back sheet” that isolates the electricity from the outside environment.

Bifacial solar panels do not contain a back sheet — this would block light from reaching the underside of the PV cells. Instead, most bifacial solar arrays appear somewhat transparent, with sunlight able to pass through both sides of the panels.

To allow for double-sided solar production, bifacial solar panels require more time and attention than traditional solar panels to manufacture and install, making them more expensive overall. The trade-off here is that bifacial solar panels have been shown to produce an average of 27% more electricity than their monofacial counterparts, according to testing by the PV company LONGi.

Bifacial solar panels: advantages and disadvantages

In the grand scheme of solar energy pros and cons, bifacial panels have their own set of advantages and disadvantages when evaluated against traditional, monofacial solar technology. The biggest overall disadvantage: Due to their cost and composition, they’re not ideal for most traditional homeowners.

Pros of bifacial solar panels

By and large, bifacial solar panels’ extra power potential is the most exciting advantage of the technology. By harnessing more of the sun’s energy, bifacial arrays can help create more solar energy in a limited space and maximize the amount of electricity generated over an installation’s lifetime.

Cons of bifacial solar panels

While bifacial solar panels do have greater power potential, they’re also currently more expensive to produce — and more complicated to install — than traditional one-sided options.

In addition to the increased manufacturing costs and expenses for specialized parts and labor, bifacial solar arrays need to be raised above their installation surface to allow diffused sunlight to reach the bottom of the panels. Because of this, bifacial technology isn’t well suited for most home installations where traditional panels could lie flat on a sloped roof.

Are bifacial solar panels worth it?

Given how much solar panels cost, investing in the industry’s emerging and most premium technologies isn’t always worth it for the average renewable energy adopter. When considering the extra total project costs necessary for bifacial energy production, two-sided solar panels usually don't make sense for residential and small-scale installations, especially on homes with sloped roof faces.

As John Striebel, CEO of Apollo Energy, a residential solar energy company in Denver, Colorado, explained, “There aren't a ton of situations in residential solar where we need to absorb light from both directions, but I can see a market for them in utility power and even things like space stations.”

Essentially, unless you’re generating massive amounts of solar electricity on a field, parking lot or rooftop, bifacial panels typically aren’t worth it when going solar today. Instead, homeowners and businesses can lower their installation costs and more accurately project their savings with traditional monofacial solar panels.

In simple terms, bifacial solar panels are an exciting technology to watch out for in the 2020s, with a clear path to widespread adoption ahead. While bifacial panels may not be worth it for most homeowners, the technology can help dramatically increase solar electricity production potential in a wide variety of commercial and utility-scale applications.

To learn more about what type of panels make sense for your installation, see our guide to the best solar energy options available today.

The future of bifacial solar panels

At the consumer level, DIY bifacial solar panels are garnering mixed reviews. With different manufacturers’ equipment varying in legitimacy and success rates, many small-scale adopters are finding that the extra costs of bifacial solar panels don’t match their anticipated results.

While the technology is in a bit of a renaissance period in the mid-2020s, it’s unlikely we’ll see significant installation rates for bifacial solar panels in residential and small-scale instances anytime soon. Instead, the market for bifacial panels is growing very quickly in large-scale, nonresidential use.