Storing Energy from Solar Windows? It could be in the near future.

by Anna Gretz
February 7, 2017

The solar panel aesthetic continues to change as technology advances, and rooftop solar designs move into a lower-profile, streamlined look. Soon, solar panels could be taken off the roof, and placed within the window pane.

The solar startup Ubiquitous Energy is well on their way to making see-through solar a reality. Vladmir Bulovic and Miles Barr of Ubiquitous Energy have spent decades of time and U.S. government funding exploring the idea of transparent solar cells, hoping that their findings would give a huge boost to an already booming industry.

Imagine: all of the energy streaming in your office window and making awkward tan lines on the side of your face could be collected and harnessed into more important things… like charging your laptop, or better yet, powering up the air conditioning.

But windows aren’t the only place transparent solar could be used, in fact, with near-invisible solar cells, the aesthetic barrier to solar inspirations would literally disappear, opening up new real estate markets to the possibility of essentially covering their commercial and residential buildings in solar cells. These solar panels wouldn’t block the heat or light of the sun, or decrease visibility. If that was the case, solar panels could be installed pretty much everywhere.

How can a solar cell both harness the energy of sunlight and let light and heat pass through the window? For that answer, we only need to revisit our middle school science classroom. You may remember that sunlight is made up of both visible and invisible light spectrums (like ultraviolet and infrared light). The idea behind these solar cells is to engineer them to only capture light from the invisible ends of the spectrum, while letting the visible light pass through. That’s the magic behind making solar panels transparent (thank you, organic chemistry.)

There is a price to pay for only harnessing energy from the sun’s invisible rays instead of all of them. You may have guessed it: efficiency. In fact, it’s a pretty direct tradeoff. It is still possible to harness a good amount of energy, but it won’t quite reach the same levels of efficiency as opaque solar cells. But this isn’t as much as an issue as it would seem, especially if transparent panels start going up everywhere (as they should.) The solar energy capacity will rise far beyond its current levels simply because of the volume of new installations, and new possible venues. The efficiency tradeoff is well worth it.

The advantages to transparent solar aren’t only in their looks, but also in the manufacturing technique. Ubiquitous Energy reports that the production process for these new transparent solar cells requires far less energy to make, bringing costs down considerably. The material is deposited by a film coating process, and doesn’t require high temperatures at all. Manufacturing through a film coating process also allows engineers to build PV panels that are extremely thin--like extremely thin. Think hundreds of times thinner than a human hair.

One of Ubiquitous Energy’s latest ideas for their ultra-thin, see-through solar cells is to sneak it into places no one would think to look for it… like underneath the device display of a smartphone. The best part about this? You won’t even notice it was there, but it would prolong the battery life of your mobile device considerably. Who wouldn’t sign up for that?

And let’s stay on the topic of batteries for a minute (you know we’re a fan of those.) Translucent solar would open up a whole new world of creative, practical solar installment venues (we already mentioned windows… but the possibilities are really endless), but there’s one thing it couldn’t do: make the sun stay in the sky longer. No matter how many solar cells you have installed, you may still find yourself dependent on grid-connected electricity after the sun goes down.

In order to truly break ties from the power grid, you need a way to store the electricity your solar panels generate during the day, so you can use it at night. Home batteries do just that. A home battery is like a power reservoir. Water reservoirs continuously provide water to overcome the intermittency of natural water flows. Home batteries ensure continuous power to an off-grid home, overcoming the intermittency of natural solar flows. With a home battery, your house can have off-grid energy, even when the sun isn’t shining.

Most home batteries on the market today are wall-mounted, indoor or outdoor systems with quiet, unobtrusive operation. Unlike gas-powered generators, they don’t need to be moved into place for operation, or refueled. With solar home batteries, there are no noxious fumes or obnoxious noise. Kind of like transparent solar cell technology, you won’t even know your home batter is there.

The combination of solar panels and home batteries provide households with the essential resources of resilient power. As builders start projects with the future of energy in mind, resilient power is set to become a new staple feature.

It’s also really important to consider the cost of not having a resilience option. For businesses, these costs are easily seen and quantified, like lost/spoiled inventory, and lost revenue from a closed facility. In residential cases, things get personal. Not only could you lose a fridge full of food and the ability to heat and cool your home, many people need electricity to sustain communication and working remotely. Others rely on electricity to power life-sustaining medical equipment. There’s a myriad of important reasons to make resilience a priority both for businesses and households.

The case for sustainability is already strong, and getting stronger. Growing environmental concerns have spurred government incentives, making sustainable design more financially viable. Consumers are also demanding more intentional, sustainable planning in housing projects, driving the sustainable building market forward. This is really good stuff. But as we create more building designs with the future in mind, it’s important to keep resilience in mind too.

Preparing for the future means thinking about protecting new, environmentally sustainable projects from the threat of unexpected disaster, and the cost of unreliable power. Homes that don’t have a way to deal with the growing natural and unnatural threats on grid-connected power are setting themselves up for failure. Power failure. In 2012, hurricane Sandy showed the country the devastating effects of prolonged power outages. Exposure to extreme hot or cold temperatures, food poisoning, contaminated water, and a shortage of life-essential supplies were just the beginning of the difficulties faced by those without resilient power. The blackout aftermath of this disaster cost the east coast both millions of dollars, and human lives. These horrible results, which added to the already overwhelming destruction of the storm itself, could have been avoided with resilience plans like solar panels and home batteries.

Transparent solar panels are a great, exciting new development in the world of solar, and a huge step toward a more sustainable, resilient energy future.

The future is looking brighter all the time.