A species of berries indigenous to South Asia may have what it takes to make solar panels far less expensive than they are now. It may even provide a lasting solution to India’s chronic power shortage.
A group of researchers at the Indian Institute of Technology, Roorkee, have found that a pigment found in jamun (Syzygium cumini) absorbs large amounts of sunlight. The IIT scientists have been experimenting with the pigment, called anthocyanin, and believe that using it for mass production could bring down solar panel costs.
“We were looking at why the jamuns are black,” said Soumitra Satapathi, assistant professor at IIT-Roorkee. “We extracted the pigment using ethanol and found that anthocyanin was a great absorber of sunlight.” Anthocyaninis also found in fruits such as blueberries, cranberries, raspberries, and cherries.
Jamun trees grow up to 30 metres and can live for more than 100 years. Across large swathes of India, the fruit – long known for its nutritional and medicinal value – is often sold at a low price on pavements and at traffic junctions.
Most solar cells today are made of either single crystal silicon or polycrystalline silicon. While polycrystalline is more efficient, it is also more expensive. Satapathi is using the jamun pigment for a new kind: dye-sensitised solar cells. The results of the study were published in the Journal of Photovoltaics.
Solar cells work on a simple principle. Photons from the sun strike a solar cell, which contains electron-rich silicon or dye, and knock out the electrons to create electricity. The more efficiently a solar cell can absorb the many photons striking it, the more electricity it can produce.
India is looking to increase its solar-power generation capacity from 10 gigawatts to 100 gigawatts by 2022 – with a target of attracting a staggering $100 billion into the sector during that time. Much of that is because the country constantly grapples with a power shortage.
Though silicon is abundant on Earth, manufacturing silicon cells is quite expensive. By using naturally occurring dyes like the jamun pigment, Satapathi hopes that if he can make his dye-sensitised solar cell more efficient, it could bring down the cost of a solar panel by 40%.
There’s a long way to go. Satapathi’s cell current efficiency is only 0.5% compared to commercial solar cells that provide more than 15% efficiency. Though dye-sensitised cells were invented in 1988, there are no large commercial suppliers of solar panels that use this technology today because of the poor efficiency of the cells.
What’s the difference between ‘a’ washing machine and a ‘great’ washing machine?
The right machine can save water, power consumption, time, energy and your clothes from damage.
In 2010, Hans Rosling, a Swedish statistician, convinced a room full of people that the washing machine was the greatest invention of the industrial revolution. In the TED talk delivered by him, he illuminates how the washing machine freed women from doing hours of labour intensive laundry, giving them the time to read books and eventually join the labour force. Rosling’s argument rings true even today as it is difficult to deny the significance of the washing machine in our everyday lives.
For many households, buying a washing machine is a sizable investment. Oddly, buyers underestimate the importance of the decision-making process while buying one and don’t research the purchase as much as they would for a television or refrigerator. Most buyers limit their buying criteria to type, size and price of the washing machine.
Visible technological advancements can be seen all around us, making it fair to expect a lot more from household appliances, especially washing machines. Here are a few features to expect and look out for before investing in a washing machine:
Cover your basics
Do you wash your towels every day? How frequently do you do your laundry? Are you okay with a bit of manual intervention during the wash cycle? These questions will help filter the basic type of washing machine you need. The semi-automatics require manual intervention to move clothes from the washing tub to the drying tub and are priced lower than a fully-automatic. A fully-automatic comes in two types: front load and top load. Front loading machines use less water by rotating the inner drum and using gravity to move the clothes through water.
The size or the capacity of the machine is directly proportional to the consumption of electricity. The right machine capacity depends on the daily requirement of the household. For instance, for couples or individuals, a 6kg capacity would be adequate whereas a family of four might need an 8 kg or bigger capacity for their laundry needs. This is an important factor to consider since the wrong decision can consume an unnecessary amount of electricity.
Machine intelligence that helps save time
In situations when time works against you and your laundry, features of a well-designed washing machine can come to rescue. There are programmes for urgent laundry needs that provide clean laundry in a super quick 15 to 30 minutes’ cycle; a time delay feature that can assist you to start the laundry at a desired time etc. Many of these features dispel the notion that longer wash cycles mean cleaner clothes. In fact, some washing machines come with pre-activated wash cycles that offer shortest wash cycles across all programmes without compromising on cleanliness.
The green quotient
Despite the conveniences washing machines offer, many of them also consume a substantial amount of electricity and water. By paying close attention to performance features, it’s possible to find washing machines that use less water and energy. For example, there are machines which can adjust the levels of water used based on the size of the load. The reduced water usage, in turn, helps reduce the usage of electricity. Further, machines that promise a silent, no-vibration wash don’t just reduce noise – they are also more efficient as they are designed to work with less friction, thus reducing the energy consumed.
Customisable washing modes
Crushed dresses, out-of-shape shirts and shrunken sweaters are stuff of laundry nightmares. Most of us would rather take out the time to hand wash our expensive items of clothing rather than trusting the washing machine. To get the dirt out of clothes, washing machines use speed to first agitate the clothes and spin the water out of them, a process that takes a toll on the fabric. Fortunately, advanced machines come equipped with washing modes that control speed and water temperature depending on the fabric. While jeans and towels can endure a high-speed tumble and spin action, delicate fabrics like silk need a gentler wash at low speeds. Some machines also have a monsoon mode. This is an India specific mode that gives clothes a hot rinse and spin to reduce drying time during monsoons. A super clean mode will use hot water to clean the clothes deeply.
Washing machines have come a long way, from a wooden drum powered by motor to high-tech machines that come equipped with automatic washing modes. Bosch washing machines include all the above-mentioned features and provide damage free laundry in an energy efficient way. With 32 different washing modes, Bosch washing machines can create custom wash cycles for different types of laundry, be it lightly soiled linens, or stained woollens. The ActiveWater feature in Bosch washing machines senses the laundry load and optimises the usage of water and electricity. Its EcoSilentDrive motor draws energy from a permanent magnet, thereby saving energy and giving a silent wash. The fear of expensive clothes being wringed to shapelessness in a washing machine is a common one. The video below explains how Bosch’s unique VarioDrumTM technology achieves damage free laundry.
To start your search for the perfect washing machine, see here.
This article was produced by the Scroll marketing team on behalf of Bosch and not by the Scroll editorial team.