Solar Cars: How Close Are We? Insights from a Global Expert Survey

he buzz around renewable energy has grown louder recently, especially about how we can weave it into our everyday lives and work. One standout topic is how we can power our rides with sunlight, through something called Vehicle Integrated Photovoltaics (VIPV). This promising avenue for green innovation has caught the eye of many in the industry, and now, a detailed report by the International Energy Agency’s Photovoltaic Power Systems Programme (IEA-PVPS) examines what it will take and the hurdles we'll need to jump to bring VIPV into the mainstream.

VIPV Explained

As we search for greener ways to power our rides, the idea of installing solar panels on our daily transport options has come up as a great solution. Simply put, VIPV is all about integrating photovoltaic modules into the structure of vehicles, from cars and buses to bikes and even aircraft. These aren't just any solar panels; they're specially designed to fit into parts like the roof or hood. Not only do they supply much-needed energy to help the vehicle run, but they also give it a sleek and attractive look, which is really important for car design. For the bigger movers like trucks and buses, the key is to use the most efficient solar panels that are light. This way, these large vehicles can still carry heavy loads without being weighed down.

Benefits: Why VIPV is a Big Deal

The benefits of switching to VIPV are huge. By making electricity right on the vehicle, it can go longer distances without needing to plug in, easing the load on electric grids and charging stations. This means hefty savings on your electricity bill for charging. Plus, using VIPV on regular gas-powered vehicles can significantly cut down CO2 emissions, taking us a big step forward in the battle against global warming. In fact, studies have demonstrated that VIPV might sometimes result in lower emissions than getting your clean power from the grid.

Overcoming Obstacles

As promising as VIPV is, getting there won't be easy. This innovative technology requires the creation of new materials and manufacturing methods that are quite different from what's used for traditional solar panels. Also, adapting the panels so they can be perfectly integrated into different types of vehicles involves tailoring manufacturing lines to each specific need, which complicates the production process. And finally, fitting enough solar panels to power a vehicle without taking up too much space remains a big challenge.

The VIPV Expert Survey: A Pathway to Innovation

IEA-PVPS's insights are drawn from a study carried out by The Netherlands Organisation for Applied Scientific Research (TNO), where 110 experts gave their opinions on making vehicle-integrated photovoltaics a common reality. This survey aimed to gather expert knowledge and views on VIPV, stepping from a special project to an everyday technology. SunValue is here to help us navigate through the study.

Survey Methods and Demographics

With the help of Survalyzer software, the researchers asked 31 focused questions and received answers from 64% of those they reached out to, clearly showing strong enthusiasm for VIPV technology. What's more, the worldwide spread of respondents proves that VIPV tech is drawing fans from every corner of the planet.

Today and Tomorrow's Solar Panel Tech

Solar panel technology is crucial for the development of vehicle-integrated photovoltaics. Currently, crystalline silicon (c-Si) is the top choice because it's both efficient and reliable. But by 2030, we're likely to see a shift to more advanced technologies like perovskites and combinations of different materials, such as thin-film on c-Si and thin-film on thin-film. These new technologies are set to surpass traditional silicon in popularity. They not only promise higher efficiency (with one combo reaching 33.9% efficiency in the lab compared to c-Si's 26.8%) but are also more flexible and lightweight, which is great for use in vehicles.

Chasing Efficiency

When we talk about how good these solar panels need to be, we're setting the bar high. No one in the survey was happy with anything below 18% solar PV efficiency that would take up a 3 square meter (approximately 32.29 square feet) section of a vehicle. This shows a strong desire for high efficiency solar panels in VIPV solutions. Surprisingly, a significant 29% of participants want to push beyond 25%, aiming to get the most efficient solar power out of the limited space available on a car's surface.

Cost Trends

Thinking about the price tag for making and setting up VIPVs? It's an important part of the conversation. Currently, it costs about 2 to 5 dollars for every watt of power these solar panels can generate. But here's some good news: by 2030, the experts expect these numbers to go way down, to just 50 cents to 1.5 dollars per watt. This big drop in solar panel cost over time means that more people will be able to afford these solar-powered systems for their vehicles, making it easier for everyone to jump on the VIPV bandwagon.

Aesthetic and Functional Harmony

When it comes to fitting solar panels on vehicles, everyone wants them to look good without losing their power. That's why the respondents prefer solar panels made with a technique known as Interdigitated Back Contact (IBC). This method cleverly hides the wiring behind the panels, leaving the front with a neat and polished look. It's a game-changer because it means that solar panels can easily blend into different parts of the vehicle, making them look great without giving up on their ability to bend and flex as needed.

Material Matters: Glass vs. Polymer

Picking the right materials for different parts of a vehicle is key for effectively using VIPV. For the roof, glass is the top choice. It's not only strong but also clear, making it perfect for letting in sunlight. For parts like doors, the hood, and the trunk, most people like to use polymers because they're lighter, flexible, and can be shaped into curves.

How Thin Should Solar Panel Glass Be?

For VIPV, the thickness of the glass covering the solar panels is more important than you might think.  Designers prefer using glass that is super thin—only 1 mm or 2 mm—because every pound added to a vehicle makes it less fuel-efficient. Research backs this up, showing that for every extra kilogram (about 2.2 pounds), a car needs a little more energy to keep going - specifically, an extra 0.04 Wh for every kilometer it drives.

The Color Conundrum

Even though most solar panels on cars are usually deep blue or black right now, 54% of people are excited about the idea of having more colors to choose from, and many are even ready to compromise on efficiency. It seems that personalizing the look of their solar-powered rides is becoming more important to users, showing a move towards more custom car designs.

Matte or Glossy Solar Panels?

The survey shows that most people like matte finishes on solar panels for all parts of the vehicle except the roof, where opinions vary. This choice is about more than just making the panels look good; it also plays a big role in how seamlessly they blend with the rest of the car. Plus, this preference might even influence how well the solar panels work.

The Road Ahead for VIPV

Looking forward, the transition of VIPV from cutting-edge experiments to an everyday feature in our cars depends on tackling some tough challenges in both tech and manufacturing. The global survey not only highlights VIPV's bright future but also points us in the right direction for research and development.

One of the big hurdles for VIPV to become more popular is the high expense — both production and PV panel installation cost. Finding ways to make these processes more efficient and cost-effective is key to making solar-powered cars an attractive option for manufacturers and buyers alike.

Safety is another big deal. It's crucial that the engineers and car makers working on VIPV systems make sure they are not just smart but also safe. Choosing materials that are both lightweight and strong, and packing the cars with essential safety features, will help make them reliable and ready for the road.

Lastly, sparking interest in this technology is crucial. By teaching people about the inner workings of VIPV and highlighting its advantages - not to mention ensuring it's both attractive and effective - we can encourage more individuals to embrace the idea of sun-powered vehicles.

Conclusion

The research shows us what's ahead for solar-powered cars: a mix of hurdles to overcome and chances to shine. As car makers move towards greener and more energy-saving solutions, the concept of vehicle-integrated photovoltaics is getting closer to making a big impact. With more research, creative thinking, and teamwork across different areas, the idea of having solar-powered vehicles everywhere is slowly but surely taking shape.