The last couple of weeks we have focused our research on the durability of flexible solar panels. In the beginning we were both a little bit lost and didn’t quite know what to do. When talking to other people we began to understand the assignment and we started our research. The beginning of this investigation started after seeing the ‘Wearable Solar’ project from Pauline. Pauline designs clothing that contain solar panels. By wearing these clothes, you can generate your own energy that you can then charge your phone with. In several interviews Pauline repeats that she thinks the production of batteries must be pushed back. In her opinion people need to use batteries less instead of more. Her wearable solar project is a reaction to this matter.
The main question we asked ourselves in this study and research is: “Can the sales of batteries be forced back through the use of flexible solar panels?”
Our starting point of the presentation was mainly figuring out how much batteries are sold in the bigger countries. Such as USA, where people buy 3 billion batteries a year and the UK where they buy 200 million AA batteries a year. In The Netherlands thats a bit more, 360 million a year. People who buy the least batteries are Australians, with 7.6 AA batteries bought each year.
We also researched which countries recycled the most and the least. Obviously Switzerland recycles the most, about 73% of the population thinks its important for the environment to recycle. France recycles the least, only 16% of the population over there recycles their stuff.
And we examined the social environment impact of batteries, so what kind of hazardous waste do batteries have and what are the highest levels of lithium in batteries.
Flexible Solar Panels
We are interested in making the world a better and much cleaner place, we hope everyone can relate to that. We digged deeper into the world of flexible solar panels, because what are solar panels exactly? Solar panels are devices that convert light into electricity. They are called “solar” panels because most of the time, the most powerful source of light available is the sun, called “Sol” by astronomers. Some scientists call them “photovoltaics” which means, basically, “light-electricity.” A solar panel is a collection of solar cells. Lots of small solar cells spread over a large area can work together to provide enough power to be useful. The more light that hits a cell, the more electricity it produces, so spacecraft are usually designed with solar panels that can always be pointed at the sun even as the rest of the body of the spacecraft moves around, much as a tank turret can be aimed independently of where the tank is going.
For us it was very interesting to know what the differences were between solar panels and normal, everyday batteries. For example, we started to examine the impact of batteries. How many batteries are sold worldwide? What percentage of it is recycled and what substances are all in a battery. We thought this would be a good starting point as a first step to understanding the problem.
We’ve also seen this from a social point of view because we believe that the flexible solar panels can be a very attractive aspect. People often are unaware of what impact some devices can have on the environment. The processing and apply of solar panels in everyday objects ensures that there is awareness is created. People feel like they are doing something good, without them really knowing they are actually doing something for the environment. A flexible solar also provides for some interaction. By example, by having a solar panel processed in your bag or clothing, means that you’ll always have electricity. You will always be online and reachable because you will never have an empty phone or laptop. This matter also connects to the generation of today, because people nowadays always want to be reachable and reconnected with eachother.
We use more and more power, because we have more electrical appliances per person available. One of our main assets is our electronic phone. Annual cost to charge your phone is approximately € 2,00 per person, each year. You might think that is not much. Now, life on this earth there are over 8 billion people. If you do the math, 2 x € 8,000,000,000,000 is a lot of money and also a lot of energy. To do something about that, we started an investigation to research flexible solar panels. These flexible solar panels are a lot easier in use than regular solar panels. Our motivation for this research came from Pauline van Dongen. Pauline is a fashion designer and developed “The Wearable Solar Shirt” in collaboration with Christiaan Holland and Chris Jan Jongerden. This is a garment that has flexible solar panels incorporated. By wearing this shirt, you upload and use your own energy and you can then recharge, for example, your phone again. After following this project we searched for several similar projects.
The development of the use of flexible solar panels is at this moment still in its early prototype beginnings. Yet there are already several people came along to work. For example, the aforementioned Pauline van Dongen. Tommy Hilfiger also, not so very long ago, developed a jacket where solar panels are incorporated. There are also new developments in the field of flexible and wearable solar panels. For example, there have been developments that are in progress at the moment in which solar cells are integrated in the yarn. This would mean that you could weave fabric so that, without you actually seeing that there is a solar cell is in it, it can generate solar energy.
After making our research question clear, we began to search for several similar projects. We asked ourselves what everyday objects can process the solar panels and how can the use of electricity and batteries be reduced, which later can be an impact on a cleaner world.
Now ofcourse the weather is not always nice here in the Netherlands, so we think it is also important, for example, to process the solar panels in several clothing pieces for optimum results. Also we think that not only clothing will be the solution but multiple different items. There are estimated 8 million cars in The Netherlands and these cars are parked for the main part of the day, so we think that would be a perfect time to charge the flexible battery.
How much energy do we use? What is the capacity of a solar panel?
So, let’s do the math! For example, we take up to 1028 watt- hours per day. If you know how many you use, it’s easier to know what you need to build batteries that can store at least this capacity. The capacity of a battery is defined by the number of Ampere Hours. The number of AH is the amount of that can supply a battery for an hour. The voltage of a general battery is usually 12 volt. If you want to know the number of watt-hours converted to the number of ampere hour, the conversion is as follows: watt hours / 12 volt (voltage divide by battery) = number of Ampere Hours.
Costs of solar panels in relation to batteries and alternatives
To determine this, we need to convert the energy value to the kWh price. The main supply (normal electricity) costs € 0.25 kWh, which is the cheapest. There’s no solar panel YET that can compete with that. But when you’re on holiday or on a nice destination abroad, there will not always be 230V ready for you to use, and if there is, you need to pay a whole lot of money for it. A 10w or 15w solar panel costs about € 200,00. It really all depends on how much you’re planning to use it. For example, you go abroad 15 days a year and the solar panel provides six hours of solar energy. The lifespan of a solar panel is very high and you can take it with you for the next 20 to 25 years. The panel provides practical 7.5W. If you do the math (yes, again) this will mean that € 200,00 (for the solar panel) / (20years, 15days X 7,5Watt or 6 hours) = € 14,80 kWh, which is quite expensive in relation to the main supply (normal electricity). But the more you use the panel the cheaper it gets.
So now for the regular batteries, lets take for example Duracell Power Plus batteries. They cost about € 4.50 per 4 X AA cells. The energy per cell, according to Duracell 2300mAh (at a discharge current of 250mA) 2300mAh X 4 X 1.5V = 13,8Wh. The price per 1 kWh => 1000 / (2300mAh 6V X) x € 4.50 = € 326, – kWh. You need to have a car nearby for this alternative, but you can always use the 12V socket. This provides the energy which is taken from the burnt gasoline or Diesel. Through the dynamo, the car battery will be charged and then our devices. According to the experts provide one kg of gasoline / Diesel 47,30MJ / 44,80MJ energy. 1 liter of gasoline / Diesel has a weight of 720gram / 840gram. 1 liter of gasoline / diesel therefore provides 34,1MJ / 37,6MJ energy, this represents 9,47kWh / 10,45kWh. At a price per liter of € 1.80 / € 1.45, 1 kWh costs € 0.19 kWh / € 0.14 kWh. Solar energy is therefore quite expensive if you only use it a few days a year. But imagine not having any power in the neighborhood and having no alternative, this could be quite a good investment.
While solar power certainly is less polluting than fossil fuels, some problems do exist. Some manufacturing processes are associated with greenhouse gas emissions. Nitrogen trifluoride and sulfur hexafluoride has been traced back to the production of solar panels. These are some of the most potent greenhouse gases and have many thousand times the impact on global warming compared to carbon dioxide. Transportation and installation of solar power systems can also indirectly cause pollution. The bottom line is this: there’s nothing that’s completely risk-free in the energy world, but solar power compares very favorably with all other technologies.
The Wearable Solar Project by Pauline van Dongen
The first project we have found was The Wearable Solar Project by Pauline van Dongen. What she did is that she processed solar panels into clothing, making it look futuristic. Solar cells have been constructed to capture solar light and convert it into electricity. Their internal structure is layered and resembles the stratified cells of the human body, which naturally interacts with sunlight. If a body is augmented with solar cells it will embody enough electrical power to become a real source of energy. For the Wearable Solar project, a coat and a dress have been designed placing solar cells close to the body. The two wool and leather prototypes comprise parts with solar cells which can be revealed when the sun shines or folded away and worn invisibly when they aren’t directly needed. The coat incorporates 48 rigid solar cells while the dress 72 flexible solar cells. Each of them, if worn in the full sun for an hour, can store enough energy to allow a typical smartphone to be 50% charged. The Sun is the biggest source of energy on earth and now that fossil fuels are depleting, it’s time we come up with a sustainable alternative.
Interview Pauline van Dongen
“Wearability is very important to my work because I am a fashion designer,” We’re dealing here with the human body and it’s not just a static body, it’s dealing with movement and expressions, a sensory surface so it’s very important to stress the wearability. We’re not very far away from people actually wearing these garments that I design. I think it’s important to see which technologies are really ready to be implemented, how people would deal with them, how people would feel in those clothes, what it could mean to them. And of course looking at the cost of these technologies. If you’re integrating 80 solar cells then of course you’re adding to the cost and you have to look at how much people are willing to pay for it.”
Atelier Teratoma “Picnic”
The second project we had found was “Picnic” by Atelier Teratoma. We thought of this as an very interesting project, because it also uses solar panels in their work. They have developed a picnic that you can charge by a solar panel. With this folding picnic set in the form of a backpack, you can charge enough energy to the park during your walk and then take your phone to charge and listen to music through speakers. The idea behind this set is about the social world we live in, people go crazy without their mobile phone.
Tommy Hilfiger Wearable Tech
This is a project from last year. They came with a range of jackets that had solar panels incorporated. The mission of Tommy Hilfiger was to make your portable charger wearable. So whenever you would be in need of a charger for example, that very important phone call, people could always reach you without having your phone dying on you. With the assistance of solar manufacturer Pvilion, the clothing label has launched a pair of jackets. For now they only designed one for men and one for women, so there isn’t much to choose from. It does, however, has an array of solar panels that will collect solar power for you so you can charge your gadgets. We thought this was kind of similar to the project of Pauline.
This project is about an optic solar cell. An international team of scientists have developed the world’s first fiber-optic solar cell. It is so small that it’s thinner than the width of a human hair and scalable to many meters in length. The silicon-based wire opens the possibility of a new generation of flexible fabrics capable of converting solar radiation into direct-current electricity.
The world’s first solar-powered wearable, fitness & sleep trackers
There are many fitness & food trackers that you can use, mostly powered by just an ordinary battery. It’s not thought through very well, because every few days you need to switch out a battery or you need to put it out in order for it to charge. Ofcourse you’ll miss out on a few steps, calories or hours that you cannot track. This is very confusing for some people. Swarovski, however, made a huge step in a new revolution. Swarovski collaborated together with Misfit wearables to make the first fitness & sleep tracker that runs on solar power. The trackers include a clear crystal face and a violet crystal face. The violet tracker is the one that is solar powered by making the crystal bend the light onto the tiny solar cell lying underneath the crystal. The solar harvesting will only work with the violet crystal tracker because the violet color makes the light more intense. The clear crystal doesn’t produce much intensity. It takes 10 to 15 minutes of sun exposure to power the wearable for a few days.
By immersing us in the world of flexible solar panels we have come to the following information. There are many different types of flexible solar panels and many different applications. At this moment the flexible solar panels are mainly used on boats and on the roofs of houses and apartments. What this means is that the solar panels will be charged up while driving or crossing sea. Therefore you don’t need to use additional power in the form of batteries or some kind – which only answers half of our research question. To really push the sale of batteries back it is necessary for products to change the normal batteries with rechargeable batteries. And by that we mean products such as a remote control, alarm clock, electric toothbrush and so on.
At this time we do not think the battery problem can be pushed back. Not necessarily because the panels are much more expensive than if you would use batteries or AC power, because we think this shouldn’t be a big problem, the money you will invest in a solar panel, will eventually pay back (within 4 years). It might be very practical, especially when there are no energy resources nearby or when power shuts down. You will always have an alternative that is cheaper than general batteries. Unfortunately, it’s not the case right now. The solar panels can only transmit energy from sunlight to the object or thing you want to give power to. So when connected directly, it will only work when sunlight is shines upon it. Which means you will always need sunlight to fully replace batteries with solar panels (unless ofcourse you saved or stored it somewhere, which you need a battery for – so then the problem is still not solved). If there is no sunlight, the solar panels will only charge lightly and not fully, which means if you need electricity it won’t work correctly. Solar power only works during the day time, and battery storage is still a few years away from being financially viable. To really benefit from solar power you need to be able to use most of the solar power as it is generated during the day, most of the time and unfortunately most people will be outdoors or at the office during the day. In our opinion it is not fully equipped to replace batteries yet.
The other main point to remember is that it is often quite easy these days to put appliances and pool pumps to run on timers. The 5 main examples are pool pumps, air conditioning/heating, the washing machine, the dryer and the dish washer. If you are able to run any or all of these on timer during the day when the sun is shining, it is not only possible to maximize the benefit of a smaller system, but you may be able to justify a much larger system, especially at the moment with low system prices and significant government rebates.
So, either it’s on a roof, tent, boat or clothing item the energy generated is only useful when you’re on the road or outdoors a lot. It is connected through a USB-portal, which makes it almost impossible to charge it without sunlight. It would be useful for example, soldiers or construction workers that work during the day. They can use their walky-talky, cellphones and/or maps using the flexible solar panels incorporated in their clothing, but not during the night.