DIY - Solar Phone Charging Unit

This article explains about how to make your own solar based mobile phone charging unit. The design is very simple and completing this should not take you more than 2 hours.

List of components required:

      1.       Solar panel : 3W,6V panel

      2.       Sealed Maintenance free lead acid battery: 6V,4.5AH

      3.       Diode: IN4001

      4.       DC -DC Step Down Buck Converter KIS3R33S Module 7V- 24V to 5V /3A

      5.       USB based mobile charging cable( Normal data cables will not work)

      6.       Connecting wires

      7.       Soldering kit

Circuit connections diagram:

Working principle:

Mobile phones have inbuilt batteries and they need to be charged every few days or every day depending on how often the mobile is used. Batteries can be charged only with Direct current whereas the electricity we get in our normal household sockets is Alternating current. A mobile phone charger does the job of converting AC to DC and keeping the output voltage and current levels suitable for mobile charging. Chargers typically have efficiencies ranging from 60-90% depending on the quality (This is why some of the chargers get heated up quickly)

On the other hand solar panels convert solar energy to DC electricity. With suitable circuitry we can store this DC electricity in an external battery and charge the mobile phone when ever required.

The selection of solar panel and battery depends on various parameters like number of mobiles to be charged and the voltage levels of the battery etc. We have used a 6V, 4.5AH battery which can charge a typical smart phone once every day.  A 3W 6V solar panel is chosen since that is enough to charge the external battery in 7-8 hrs. The solar panel is directly connected to the battery with a diode in between to avoid reverse flow of current from the battery to the solar panel when there isn’t enough sunshine and during night time.

A DC-DC converter module is used to convert 6V battery voltage to 5V output since mobile batteries are very sensitive to charging voltage and current( a normal car battery regulator can be used but the efficiency is very low)

Construction:

·      

            As shown in the circuit diagram, connect the positive end of the solar panel to the positive end of the diode (silver ring on the diode represents negative) and the negative end of the diode to the positive of the battery. The negative end of the solar panel can be directly connected to the negative terminal of the battery.

·         Solder the terminals and use insulation tape to make sure shorting of terminals doesn’t happen.

·         Identify the input side of the DC-DC converter and connect positive and negative of the battery to the positive and negative of the DC-DC converter input respectively.

·         The output of the DC-DC converter is a USB port where the charging cable is inserted. (Note: Normal data cables do not work so a simple charging only cable should be used)

·         If the connections are proper, you should be able to see a red light glow on the DC-DC board and your mobile phone should display charging.

·         We had used a voltage and current measuring device called a charger doctor at the output to verify if the voltage and current levels are in the suitable range. This unit is not required.

Try this fun project and let us know your experience or queries in the comments section below.

Where to buy?

1.       Solar panel : http://www.amazon.in/Sparkel-Solar-Panel-meter connection/dp/B01EB0C06Q?tag=googinhydr18418-21

2.       6V battery : http://www.amazon.in/6v-4-5Ah-SMF-VRLA-Battery/dp/B00MPJ66UM/ref=sr_1_1?ie=UTF8&qid=1474624382&sr=8-1&keywords=6+v+battery

3.       DC-DC converter : http://www.amazon.in/Converter-KIS3R33S-Module-Replace-KG106/dp/B00YURPEL4?ie=UTF8&psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00

4.       Diode IN4001,connecting wires, soldering kit and charging cable : Any regular electronics store

Clean water mania - the marketing and the wastage

We all go to restaurants every now and then and the first thing we get asked by the waiter is “Normal water or mineral water?” How many of us at that stage have thought to ourselves – “Why is he asking me this? Maybe the water is not that clean here, should I just order mineral water?” and often times we end up asking for mineral water.

We attend conferences in huge 3 star or 5 star hotels and we get small plastic bottles of packaged water. How many times have you opened a bottle, had some water and then forgotten about it? In conferences that last for an entire day, have you seen lots of half filled, used water bottles? Is that wastage justified? A similar sight can be seen at Indian weddings. Partially filled water bottles are strewn around everywhere. Isn’t that a huge waste of resources?

A reputed 5 star hotel must have a good water filtration system and they can provide clean potable drinking water even through their taps. Then why do they serve packaged small plastic water bottles? Because we as consumers look for it. It gives us a false sense of security that the packaged water is best. In other words, it indirectly creates a negative image of the regular water which has been filtered. The same goes in weddings that happen in established venues. A good venue must have the capacity to serve clean drinking water but thanks to the demands and expectations from us, the consumers, we can see lots of plastic bottles strewn around and water being wasted. In fact, we probably won’t have the same bottled water, if it was poured in jug and kept in front of us.

We have let this notion of ultra clean water dictate our preferences when it comes to using water. The biggest blunder being Reverse Osmosis. RO is a technology that must be used for water with high levels of salinity and dissolved solids. It is a technology that has to be used ideally in desalination plants for treating brackish water or sea water and not in regular households. The human body is capable of dealing with water that has a TDS of up to 500 ppm. Below is a part of the IS 10500, the Indian standard for drinking water which clearly states that the acceptable limit for TDS is 500 ppm. This indicates that drinking water around 250-300 ppm is good enough. ROs tend to over purify the water.

  

ROs tend to purify the water to a TDS level of well below 75 ppm. Doesn’t that mean the water is purer? Perhaps. Is it what the human body needs? Certainly not. It is wasteful to use an RO in locations where the water can reach potable levels with simple activated carbon, sand filtration processes. In fact it is criminal to use RO in such places. By over-purifying, the water not only becomes pure but it becomes “hungry”. It is ripped off of its minerals and other soluble components to such an extent that now it wants to dissolve things in it. Studies also claim it becomes mildly acidic. Not to forget the reject stream of water that is more impure than the input water. Where does the reject water go? It enters our drains and eventually it will end up polluting our existing water bodies.

Have a look at the following pictures

On the left there is natural mineral water for which IS 13428 is the standard. On the right is packaged drinking water for which IS 14543 is the standard. The difference between the two is that natural mineral water is fresh water harvested and carefully packed at a natural source, typically these are fresh water streams up in the mountains. It has natural minerals. On the other hand, the packaged drinking water is regular water, perhaps from a ground source that is filtered, purified and packed. While we spend around Rs.20 per liter for packaged water (on the right, blue label), we shell out around Rs. 60-100 per liter of natural mineral water (on the left, pink label).

 If one looks closely at the pink label of the natural mineral water, this is what it shows.

Dissolved solids, or TDS range is 300-330 ppm. It is enough to show that on one hand we are spending Rs.100 for a liter of water at 300-330 ppm but on the other hand, we become fussy and particular about using ROs and having over purified water at less than 75 ppm. The problem is in the mindset that the industries involved in water have created by marketing and superior packaging. As stated earlier, if one serves the same water in a steel jug, most people would be reluctant to drink it. The colourful packaging along with the plethora of details make the water in these bottles look “purer” whereas the fact is that they are probably only as good as the regular filtered, pathogen free water.

We have collectively fallen prey to the marketing gimmicks and allowed an ultra-clean water paranoia seep into our minds thereby creating an ecosystem that is resource intensive, high in carbon footprint and immensely wasteful.

 We all can do a few things to make things a little better:

         1.       When you attend conferences, wedding etc. and are served packaged water bottles, make sure you drink all the water. If there is water left in it, carry the bottle with you, drink it and dispose the bottle responsibly.

        2.       Wherever possible, avoid packaged water bottle. When you go to good restaurants, they will have regular water that is clean and filtered. Go for regular water. Save the environment and save money!

         3.       At home, one can test the TDS of tap water and accordingly take a decision on whether to setup a regular filtration system or an RO. Chances are that a regular filtration system is enough to give you necessary quality of water.

       4.       If RO has been installed at your home, use the reject water judiciously. Store it and use it to water the plants after mixing it with regular tap water. One can also use the reject water to mop the floor or wash the utensils after mixing it with regular tap water.

Water is an essential resource for the survival of mankind. Let’s use it judiciously and mindfully.

Innovations in Energy Storage – Key to Renewable Energy Adaptation

Renewable energy (RE) is the source of energy that are naturally replenished and thus don't deplete. The most common types of RE are solar and wind. These are the ones that are predominantly used around the world today. While wind turbines harness the kinetic energy of the wind to convert it into electricity, solar technology has more variants. Both heat and light from the sun can be utilized to generate energy. Solar thermal and concentrated solar power use the sun’s heat to produce energy and work while Solar photovoltaics (PV) or commonly known as solar panels use the sunlight to produce electricity.

All those who have been fairly accustomed to the proceedings in the renewable energy technology understand the pros and cons. While significantly lower levels of environmental impact is a major advantage of RE, it still hasn’t picked up well enough and hasn’t quite been able to compete with the conventional sources (Coal, Gas, etc.). RE technology, or at least the two most popular ones, Solar and Wind have a major drawback. The sun doesn’t shine all the time and the wind doesn’t blow continuously. This makes the energy produced by these technologies intermittent. Add frequent weather changes and it can be observed that one cannot solely depend on these technologies for their energy needs. These cannot serve the base load. We still need coal, gas or nuclear powered plants to serve a steady, continuous base load.

Energy storage is considered as the answer to this problem. It is a well-known concept and the most widely used method of electrical energy storage are batteries.

Batteries have been used for many years now in a variety of applications. They have been improved significantly over the years, from bulky lead acid batteries to sleek and powerful Li-Ion batteries that are light weight. Batteries are a topic that has been subject to tremendous research. They may look like a simple device but they are quite complex in the sense that they get affected by too many parameters. The charging current, discharging current, operating temperature, depth of discharge, the duration for which it has been kept unused and the amount of variation in load are some factors that affect the life and efficiency of a battery. It is nearly impossible to get the best of everything and as a result, a typical battery works well for not more than 3-4 years. In the case of renewable energy, where a power plant lasts for about 25 years, a battery bank to store the energy is a great idea but it also means a recurring expense of replacing the batteries every 3 years. This increases overall project costs over the lifetime. That being said, a well-designed battery bank connected to a solar power plant will ensure a steady supply of power thus eliminating the intermittent nature of the energy generated. In order to do that, the batteries need to be lighter, cheaper and have a higher energy density (more storage in reduced space). Many organizations are currently researching batteries, from mobile phone manufacturers to electric car makers.

Li-Ion battery (left) and lead acid battery (right)

While batteries are capable of storing electrical energy, thermal energy storage requires a completely different arrangement. In a solar thermal device, which is equally intermittent, the heat generated while the sun shines may be stored in special arrangements for later usage. It is in some way like a thermos flask that traps the heat in the coffee and keeps it warm for a long time. There have been many materials and compounds that have been explored which can store heat or cold and release it according to the user needs. These are primarily Phase Change Materials (PCMs) that change phase (solid – liquid –gas) when subject to heat or cold and stay in the new phase for a considerable time till the energy is removed externally. Salts have been researched for this purpose. Excess heat from say an oven can be pumped into an insulated chamber of salt using conventional heat transfer methods. This melts the salt (solid to liquid). Due to insulation of the chamber, the heat that has been put in remains in for a considerable time. The heat from the molten salt can be extracted later using conventional methods and utilized for various processes. A technology like this will enable solar water heaters to provide hot water even during the night. Phase change materials are various compounds that work in different temperature ranges. They can be selected according to the application whether it is heating or cooling. PCMs have found niche uses in a wide spectrum ranging from lunch boxes to Neonatology. PCMs last for about 3-4 years which again leads us to a recurring expense every 4 years when integrated with a RE setup. A lot of effort is being put to improve the cyclic performance and durability of PCMs.

We might have also noticed that stone and concrete floors tend to get really warm during summers. For example, anyone who has been to the Taj Mahal will remember the hot marble floor on which one has to walk barefoot. Getting inspired from these, research is being done on thermal energy storage in concrete and stone blocks.

In conclusion, it is evident that a breakthrough in energy storage, whether thermal or electrical is the key factor that will lead to extensive adaptation of renewable energy systems. By addressing the core disadvantage of RE, i.e. intermittent nature of RE, energy storage technology might make all the difference in the years to come. 

DIY - Solar Car

Yes! You read that right. We are going to build a car which runs only on solar energy! Well, a solar toy car to be exact.  If you are interested in playing around with solar panels, motors, wheels etc. then this article is for you. What better way to spend your leisure time building a solar toy car and flaunt your engineering skills with your friends and family, right?

This is a very simple yet exciting project for any class 8 and above student. With all the right components in place, it should take you anywhere between 1-2 hours to finish this. An instruction video is attached in the end and in case you get stuck somewhere, feel free to drop your queries in the comment section.

Let’s get started

You will need the following components. We bought our components from various places in Delhi NCR, like Chandni chowk , Sadar bazaar etc. you can order the components online and the link for each component is attached in the end.

	Component	Quantity
1	60 RPM DC motor	2
2	Dummy for the wheels	2
3	Wheels	4
4	3W solar panel	1
5	Soldering Iron	1
6	Wire stripper	1
7	Insulation tape	1
8	Soldering wire	1
9	Shoe box	1
10	Ruler	1
11	Connecting wire	1m
12	Tester or screw driver	1

This is how most of the components look like.

Once you have bought all the components and identified each of them, it should be fairly simple to finish the project.

Construction principle

This will be a four wheeled toy car. These wheels should be attached to the sides of a shoe box in the way shown in the picture below.  Make sure that the wheels are aligned i.e. the line joining the centre of the two wheels should be parallel to the side of the box (red line is parallel to the side of the box). Height of the wheel from the box edge is chosen in such a way that the cardboard doesn’t touch the ground when the car is resting on the wheels.

We need motors to run these wheels. A motor each is attached to both the back wheels. The other two wheels in the front are fixed with a dummy. These motors run on DC electricity and this will be provided by the 3W solar panel.

The job of the solar panel is to convert solar energy (sunlight) to electricity. Every solar panel has a junction box behind it. When you open the junction box, you will find two terminals namely a “positive +” and a “negative -“.

Connect wires to these terminals. The convention is to use a red wire for the positive and a black wire for the negative. This makes it easy to identify, helps avoid shorting and makes the connections easier. The other end of wires are connected to the motors as shown below. Use soldering iron to solder the wire on to the motors. A hump in the circuit diagram signifies there is no connection at that point. In this case, there is no connection between the black wire and the red wire.

To test if you have soldered properly, place the panel in direct sun light and see if both the motors rotate. Use trial and error to figure out the correct connection to the motors so that the car moves forward. Once you have figured the right combination, solder the joints and use insulation tape to cover the open ends.

The final product should look something like this.

or may be like this

Where to buy the components?

60 RPM geared DC motor

Motor Dummy

3W Solar Panel

Wheels

Wires

Soldering station

Check out the video

And here is a video of a solar toy car race that we conducted for school children: Solar Toy Car Race

Enjoy and let us know your experience with this

A green supply chain is the key to surviving the competition

The time is 15:00 hours. The production in the factory is going on, business as usual. The assembly line is churning out piece after piece. The QC team is inspecting each piece and separating the good ones from the bad ones. The shop floor supervisor is on his rounds. But for a change, he is accompanied by the top members of the HR and Compliance departments. They are scouting the place for potential NCs (non-compliances) in order to fix them. This is NOT a usual activity. The HR head doesn’t come to the shop floor unless it is something very important.

Outside the building, there is a team of workers cleaning up and organizing the huge front lawn, the waste segregation area is being sorted and labelled too and the hazardous waste area is being improved upon and so on.

Is this usual practice? Perhaps not. Most likely the MD or a major customer is showing up for a visit (read: audit) the next day. Does this sound familiar?

Industries in India, particularly the MSMEs and the OEM ancillaries are known to adopt such last minute corrective measures when it comes to compliance and sustainability. Many of them look at environmental compliance (EHS) as a hurdle that affects their day-to-day production targets. Such industries often look at the corrective measures as something that is painful to do as a result of which, the steps taken are often half-hearted and are temporary fixes (till the so called audit gets over)

Times are changing. With the advent of our Hon’ble PM’s Make in India campaign, more and more international companies are looking to setup shop in India. These international players and many Indian OEMs understand the importance of monitoring the impact on the environment by their production processes. Natural resources are limited and big companies realize that they are going to survive the competition only if the resources being put into their activities are used judiciously with minimum environmental impact along with substantial efforts to give something back to the nature. The Government policies have evolved to ensure large corporations indulge in socially and environmentally benefiting activities. While Corporate Social Responsibility (CSR) initiatives take care of the latter i.e. giving back to the nature/community, the former requires an effort not just from the company but also from its entire supply chain.

In the case of large companies or brands, the task of production is outsourced to the MSMEs entirely or in parts. This is where the major chunk of resources are being used. Once the piece is checked, packed and shipped to the Brand, there is hardly any natural resource used. Perhaps just the fuel for transportation. Major international brands, who don’t have a retail presence in India, have their supply chain here. This is particularly true in the garments and accessories sector. This essentially means that products being made in this country are going around all across the world. They have to meet international standards not just in terms of product quality but also in terms of process responsibility. Therefore, the big companies target their supply chain. They enforce the international standards on these MSMEs. Those who comply, stay in the business while those who can’t, lose out. These MSMEs may in turn push their vendors to go green in their processes or change their vendors altogether. Indian OEMs who export their products need to meet international standards and have been known to conduct elaborate green vendor development campaigns encouraging their suppliers to adopt energy and water efficient technology along with a strong check on pollution and waste management.

Another point of view is at a national level. The factories in India or the ones that will get setup thanks to the Make in India campaign will be exploiting the resource within this country. They will be impacting the local environment here. By using the limited and critical resources in an irresponsible way, one is paving way for a day in future when most or all of the resources and raw materials will have to be bought from more expensive sources. This will shoot up production costs which is how one loses out in competition to start with. From a national perspective, all the Indian industries contribute to the GDP or in other words, in some way they are the supply chain of India. Just like they step up their efforts towards greener production for business with international brands, they have to step up their efforts for the future of the country and nature.

It’s an Investment, not an Expenditure

All these efforts will certainly lead to some expenditure on the supplier’s part. They might have to retrofit their boiler or tie up with an agency for handling their waste. But it is more of an investment because not only such measures make the factory resource efficient and lead to financial savings in operations, but they also ensure that the factory stays in competition by continued, if not more, business from the OEM.

A factory adopting green and sustainable production practices has a huge marketing instrument in its kitty. International brands coming into the country from setting up a supply chain will look for vendors who are better adhered to international standards. This makes their job easy and gives the factory an edge over others who might not be that compliant. One must look at these efforts as investment put into business development.

Some common steps for resource efficiency

When it comes to sustainable practices, it is important to understand that not all efforts require money. Most factories need simple steps to improve efficiency and reduce environmental impact. These are the low-hanging fruits which require little to no investment. Simple steps can lead to huge impacts, such as
-          Encouraging shop floor workers to switch off the lights of the floor during lunch, or
-          Asking the maintenance team to do regular checks on leaking water and steam fixtures.
-          Periodic maintenance of machines is a simple but very powerful step towards efficiency.
Preventive maintenance is always better than corrective maintenance. Large OEMs are known to take a week of shut down just to do thorough maintenance of their equipment.

Once the low –hanging fruits are harvested, one may look at upgrades requiring investment. Some steps are:
-          LED lighting in the factory
-          Energy efficient drives for pumps, motors and compressors
-          Heat recovery and Thermal storage and so on.

 Health and Safety

While resource efficiency is one part of the entire process, health of the workers and safe practices form the other components.
-    Ensure the workers are trained to work in a prescribed safe manner and the necessary paraphernalia is available (protective equipment, first aid kits etc.)
-          Form a small team with representatives from all departments and conduct internal audits monthly. Identify NCs and correct them and review them regularly.
-          Conducting regular third party trainings on Environment, Health and Safety gives a different perspective on the status of things within the factory.
-          Conduct regular fire safety and disaster management drills
-          Benchmark best practices from competitors and develop unique practices drawing inspiration across various sectors.

In conclusion, it is easy to make a product but not so easy to make the same thing in an environmentally responsible way. Those who can do it, survive.

Wastage, Inflation and Carbon footprint

Agriculture sector is the largest employer in India with over 58% of rural population’s livelihood dependent on it, and contributing to 17% of India’s GDP.  In 2013-14 the agricultural food production was found to be 263 million tonnes, which is 8.7% higher than our demand of 230 million tonnes per year. Yet there are many questions cropping up, like,

      1.        Why are about 50% of Indian children reported under nourished?

     2.       Why does India rank 63 out of the 78 countries listed in the Global Hunger Index of 2013? (It ranks worse than neighbouring Sri Lanka, Bangladesh and Pakistan)

     3.       The supply of food is much higher than what is needed. By the law of supply and demand, the prices should have gone down. Why is there inflation in food?

   

      4.       What implication do these have on the environment?

The root cause is wastage. Yes, in a developing country with 50% children who are smaller for their age, we waste food and lots of it. The fact is that production wise, we have it pretty much covered. The losses in transportation and storage are the real devils. Lack of cold storage facility near the production areas, improper packaging, and lack of cheap, efficient and appropriate transportation means are major feeders to this evil. It was estimated that in 2013-14 India wasted 21 million tonnes of wheat alone, which is as much as the entire food production in Australia!

The production of food more than what is needed is meaningless since we waste so much that the actual available food is much lesser than what is needed. This is the reason why food inflation is rampant.

Even when assuming the demand for food is the same (which in all practical aspects is ever increasing) the price increases as there is simply not much food available in spite of producing huge quantities. Thanks to wastage. In the actual scenario, the price will only go further up as the demand for food keeps on increasing while we keep on wasting the food we produce.

As a result of this, everything becomes costlier. The poor farmer who worked hard to produce the food that gets wasted is not excluded from the list. The resources used to produce food gets costlier, as a result, the farmer is unable to churn out a healthy livelihood.

It takes somewhere between 500 liters to 4000 liters to produce a kg of wheat. Even going by the lower limit, by wasting 21 million tonnes of wheat, the country has wasted 10.5 trillion liters of water which is equivalent to the consumption of water by the entire population of Uttar Pradesh for a whole year! That is a lot of water. Using this much water in agriculture would have needed electricity for pumping it. All that electricity has gone waste leading to a whole lot of GHG emissions put out into the atmosphere for nothing. This extends to tonnes of coal wastefully burnt in our thermal power plants to produce the electricity used to pump the water.

By wasting food, we put a stress on the natural resources which are harnessed and mined to provide the raw materials for its production. This results in an increased Carbon and water footprint. Wasting animal products and meat leads to a much higher Carbon footprint than vegetables and fruits as meat and dairy require more resources.

Due to wastages, the actual food availability goes down thereby increasing the prices. We have to stop wasting food.

In order to do this, the supply chain needs to be improved at a national level. In India, we can see farmers transporting their produce on rickety, inefficient, non-refrigerated trucks, driving through the bad roads bearing the dust and heat. The cold chains used for storing the produce are far from the site of production. India needs more cold chains and they have to be at the site of production. Our country needs improved, refrigerated vehicles for transporting food. It needs better roads and better goods trains to play a part in reducing food wastage.  New technology that use thermal energy storage to reduce electricity expenses must also be explored.

At a personal level, each individual can take efforts to minimize food wastage. Simple practices include-

    1.       Buying smaller, usable quantities. Try not to throw away any raw food from the house. Pay attention to your family’s eating habits and buy accordingly.

      2.       Discourage family members from throwing away good food, both cooked and raw.

     3.       If a lot of edible food is left, give it off to those who need it. There are plenty of NGOs that can help you. You yourself can just walk out of the house and find someone who will be happy to eat that.

      4.       Reduce the intake of processed food. The more processed it is, the more resources it has used up in its journey to reach you. By extension, you will be wasting more resources if you waste processed food.

     5.       Never waste food in restaurants. Always get them packed and use it at home or give it away to someone in need.

Remember, when you waste food, you also waste water, energy, money and a poor family’s hard work. In addition to that you also contribute in increasing your Carbon footprint and rising inflation.

Stop food wastage. Stop it now!