Tuesday, March 31, 2020
Monday, March 30, 2020
How to make a solar oven
HOW TO MAKE A SOLAR OVEN
Use the sun's energy to heat up A TASTY TREAt with this simple solar oven! Have you ever heard the expression that it's so hot out you could fry an egg on the SIDEWALK? Have you ever wondered if it's true? Find out with this easy, fun, and delicious solar oven science project that uses only household items and a pizza box. Plus, learn about absorption , insulation, and the sun's energy.
Want even more solar energy science? Check out these solar energy science projects. And for another edible science project that teaches about insulation, make Baked Alaska.
What You Need:
Cardboard pizza box (the kind DELIVERED PIZZA comes in)
BOX KNIFE or scissors
Aluminum foil
CLEAR TAPE
Plastic WRAP (a HEAVY-DUTY or FREEZER ZIP LOCK BAG will also work)
Black CONSTRUCTION PAPER
Newspapers
Ruler or wooden spoon
Thermometer
An adult to help with cutting
Recipe Ideas
SOLAR OVEN RECIPES
Or buy a SUN SPOT SOLAR OVEN KIT>>
What You Do:
1 Use a box knife or sharp scissors to cut a FLAP in the lid of the pizza box. Cut along three sides, leaving about an INCH between the sides of the flap and the edges of the lid. Fold this flap out so that it stands up when the box lid is closed.
2. Cover the inner side of the flap with aluminum foil so that it will reflect rays from the sun. To do this, TIGHTLY WRAP FOIL AROUND THE FLAP, then tape it to the back, or outer side of the flap.
3. Use clear plastic wrap to create an AIRTIGHT WINDOW for sunlight to enter into the box. Do this by opening the box and taping a double layer of plastic wrap over the opening you made when you cut the flap in the lid. Leave about an inch of plastic OVERLAP around the sides and TAPE each side DOWN securely, SEALING OUT AIR. If you use a plastic bag, cut out a square big enough to cover the opening, and tape one layer over the opening.
4. LINE THE BOTTOM OF THE BOX WITH black construction paper—black absorbs heat. The black surface is where YOUR FOOD WILL BE SET TO COOK. How much you need will depend on the size of the pizza box you're using to make your solar oven.
5. To insulate your oven so it holds in more heat, ROLL UP sheets of newspaper and place them on the bottom of the box. Tape them down so that they form a border around the cooking area. It may be helpful to also TAPE THE ROLLS CLOSED first. The newspaper rolls should make it so that the lid can still close, but THERE IS A SEAL INSIDE OF THE BOX, so air cannot escape.
6. The best hours to set up your solar oven are when THE SUN IS HIGH OVERHEAD - from 11 am to 3 pm. Take it outside to a sunny spot and adjust the flap until the most sunlight possible is REFLECTING OFF THE ALUMINUM FOIL AND ONTO THE PLASTIC-COVERED WINDOW. USE A RULER TO PROP THE FLAP AT THE RIGHT ANGLE. You may want to ANGLE THE ENTIRE BOX by using a ROLLED UP TOWEL.
7. You can make toast by buttering a slice of bread then letting the sun do the rest. Cooking a hot dog or making NACHOS WITH CHIPS AND CHEESE are also fun treats to make in your solar oven! It would also work great to heat up leftovers. So the paper at the bottom doesn't get dirty, put what you would like to cook on a CLEAR PLASTIC OR GLASS PLATE. A pie plate would work well. Place the thermometer inside your oven before you close it, so you can check the temperature [??? Isn't it risky for fitting the whole thing].
8. To take food out of the oven, open up the lid of the pizza box, and using OVEN MITTS OR POTHOLDERS, lift the glass dish out of the oven.
What Happened:
The heat from the sun is trapped inside of your pizza box solar oven, and it starts getting very hot. Ovens like this one are called COLLECTOR BOXES, because they collect the sunlight inside. As it sits out in the sun, your oven eventually heats up enough to melt cheese, or cook a hot dog!
How does it happen? Rays of light are coming to the earth at an angle. The foil reflects the ray, and bounces it directly into the opening of the box. Once it has gone through the plastic wrap, it heats up the air that is trapped inside. The black paper absorbs the heat at the bottom of the oven, and the newspaper make sure that the heat stays where it is, instead of ESCAPING OUT the sides of the oven.
Your solar oven CAN REACH ABOUT 200° F on a sunny day and will take longer to heat things than a conventional oven. Although this method will take longer, it is very easy to use, and IT IS SAFE TO LEAVE ALONE while the energy from the sun cooks your food.
We made a cheese roll up by melting cheese on a CORN TORTILLA. It took about 45 minutes for our cheese to melt and the tortilla to become soft. The internal temperature of our pizza box solar oven was 125° F.
If you do not want to wait long to have a solar-cooked dish, try HEATING UP SOMETHING That HAS ALREADY BEEN COOKED, like LEFTOVERS, or a can of soup. Putting solid food in a glass dish and liquids in a heavy plastic zip lock bag works well. You can also PRE-HEAT YOUR OVEN BY SETTING IT IN DIRECT SUN FOR UP TO AN HOUR.
Other recipes you may want to try are making baked potatoes, rice with vegetables, CHOCOLATE FONDUE, S'MORES, and roasted apples with cinnamon and sugar.
Even on partly cloudy days there may be enough heat and light from the sun TO SLOW COOK a special dish.
Here are a few tips for having success with your solar oven:
Stir liquids (if you're cooking something like fondue, rice, or soup) every 10 minutes. You can rotate solid food every 10-15 minutes as well, so IT COOKS EVENLY.
Reposition your solar oven when needed, so that IT FACES DIRECT SUNLIGHT. You SHOULD BE CHECKING periodically on your oven, TO MAKE SURE it is in the sun.
Make sure that the foil-covered flap is reflecting light into the pizza box, through the plastic-covered window.
To experiment further with solar cooking, make your own SOLAR PURIFIER with this science project!
For more ready-to-go science projects, see Solar & Alternative Energy Kits.
Source: https://www.homesciencetools.com/article/how-to-build-a-solar-oven-project/
HOW TO MAKE A SOLAR OVEN FROM AN OLD ANTENNA DISH
Solar ovens are very eco-friendly cooking methods and are used all over the world. People actually use this to cook dinner and things. So whether or not this is long-time or just for fun, solar ovens are very neat things to make.
Steps
1
Obtain an old satellite dish. Make sure it's in ok condition.
2
Gather your materials. You'll need the dish, aluminum foil, insulation (e.g. newspaper), black paper, a STAND, and some tape.
3
Lay the dish on the ground. Fold up your insulation so it's a triangle that's the shape of one of the ribs. Tape it together.
4
Now for the foil. Make sure it's flat! Otherwise it will not reflect AS WELL. Put it (shiny side up) on the insulation and Tape Or Glue it to the satellite.
5
Repeat the previous two steps until covered.
6
Now is the time for the paper. Tape the black paper to the outside of the dish. (This step is actually optional, so skip it if you don't want it.)
7
STAND IT ON THE STAND, directing to the sun. You now can cook all the food you want using the focus on the sun.
Source. (with pics):
https://www.wikihow.com/Make-a-Solar-Oven--from-an-Old-Antenna-Dish?amp=1
posted from Bloggeroid
Friday, March 27, 2020
7 Best Solar Power Banks in 2020 (Review)
5 Tips for Choosing a Solar Power Bank
When going to purchase a portable solar power bank, there are many questions that may arise as you check on the products. If you have any doubts about which factors you should take into account when choosing one of these products, then you will find these tips very useful.
Check the Battery Capacity
Maybe the most important factor of any solar power bank is the capacity that the lithium battery has.
The battery capacity represents the amount of energy that can be stored inside the backup battery and is generally expressed using mAh or Wh units.
A portable solar power bank could have as low as 2000mAh of battery capacity which could be enough to charge your device (probably a single charge of a cellphone), this can be classified as a small solar power bank.
On the other hand, the device could also have as much energy capacity as 50000mAh which could be enough to charge tablets, charge your smartphone or laptop several times. This can be classified as a large solar power bank.
As you can presume, cost and also weight vary according to these facts. Therefore, you must select the solar power bank taking into account the purpose for which you are going to use it.
If you are going to use this external battery for your daily life on the city or town and you simply want to have a backup battery in case you RUN OUT OF POWER, then you will probably only need a simple 2000mAh portable solar power bank.
However, if you are looking to have a backup battery that lasts for days while being off-grid on a camping trip or when going hiking, then you will need a larger solar power bank with capacities between 10000-50000mAh depending on the number of days.
Also, remember that a large capacity always demands more time to charge completely.
Think About Portability
The main idea of a portable solar power bank is to provide a reliable power source while being off-grid, but without representing any important sacrifice in the process of carrying the device from one place to another.
Top portable solar chargers should take this fact into account and offer the small, lightweight, and easy to carry solution.
If you are evaluating several options, then consider which ones are foldable, which power bank includes a STEEL LOOP to hang it on the backpack WHILE YOU WALK (it’s crucial to take advantage of the time to charge the battery while you walk), and which one is smaller.
Another important fact must be taken into account in portability is related to durability. Since it will probably be performing in outdoor activities, it is very important that the battery and the solar panel have a protective cover against water, dust, and shocks
Verify Solar Panel SPECS
The main purpose of choosing a solar power bank battery charger is that it charges the battery using the Sun’s energy without depending merely on power from the grid.
Since the main source of power here is the solar panel, it is crucial to examine the quality of the solar cells.
Efficiency is the most important factor here. If efficiency is low, the device will need larger portable solar panels and much more time to get the battery fully charged, which impacts portability.
No other brand in the world offers a better efficiency for solar cells than SunPower. Therefore, if you have to choose between a solar charger power bank with SunPower solar panels and another product that is less expensive but that uses unknown solar panels, the best choice is to go with the SunPower one.
How Many Available USB charging Ports Does the Solar Power Bank Have?
One of the greatest features a power bank can have is to be able to charge multiple devices at the same time.
Most power banks will have dual USB ports. However, you will find some that may have three USB ports included of different types and for different devices.
This is very useful as it means that within the same time range you could charge your laptop, your smartphone, and your iPad. If the solar power bank you are evaluating, only has a single USB port, then it is not worth it.
Additional Features
As usual, the extra feature that the manufacturer wants to add to the power bank always balances the equation.
Features such as LED indicators, LED LIGHT MODES OF OPERATION, steel loops for hanging, aesthetic design, Quick Charge 3.0 USB ports, and included accessories such as a USB cable or an adapter are always factors that could help you take a decision.
How Much Should I Expect to Pay for a Top Solar Power Bank?
As we mentioned before, the price will be directly related to the battery capacity, but also to the solar panel technology and the brand.
A good quality solar power bank should never cost more than 60 USD.
Price ranges for power banks with capacities between 10000mAh and 20000mAh should be located between 20USD and 30 USD. Over 20000mAh you could expect prices to rise to 40-50USD.
What Devices Can I Charge?
In most cases, solar power banks are used to charge the following electronic devices:
- Smartphones
- Laptops
- Tablets
- iPhones
- iPads
- GoPro Camera
- GPS
- Portable speakers
- Portable radios
The possibility to charge an electronic device or not will depend on the USB port type of the solar power bank. Most products have a universal USB output, but some have micro-USB or type C charging ports. In any case, you can always look for an adapter to connect your phone.
What Phones Are Compatible?
Most cell phones are compatible with solar power banks because most cell phones can get connected to a universal USB port. Therefore, you can use a power bank to charge smartphones such as:
- iPhone X, 8 7, 6.
- Samsung Galaxy S8
- Samsung S8 Plus
- LG Stylus 2
- Windows Phones
- Sony Xperia Z2
- Nokia 1 Plus
- And many more
Every smartphone has a lithium-ion battery that you can check on the specs of your phone. All you need to do to verify whether or not your solar power bank is suitable to charge your phone. First, check the battery capacity of the smartphone in mAh.
Then, divide the battery capacity of the power bank when its fully charged by the energy needed by the smartphone. You will then will find the number of times that the power bank can charge your phone.
Also, take into account the type of charging ports that the smartphone needs and see if the USB solar power bank includes it. If not, simply purchase an additional adapter.
Another fact that you could take into account, which is not limiting but worth knowing, are the AMPERES that your cell phone needs to charge.
Universal USB outputs have a 2A output, however, you may find some with 2.1 A, 2.4A or even 3A. This will influence the charging speed of the mobile phones, but could also impact the performance of the battery since cell phones are designed with a specific NOMINAL electric current.
Check the battery specs of your smartphone to see if the nominal electric current demanded is lower or higher than the one of the USB port, if it is lower, then there is no problem, the power bank will only provide the current that the phone needs. But, if it’s higher, consider looking for another power bank.
Roughly How Long Does a Full Charge Last?
The answer to this question varies from user to user, from power bank to power bank, and from smartphone to smartphone.
Basically, the battery capacity determines how long the fully charged power bank will last.
As an average range to take into account, a fully-charged 24000mAh solar power bank should be able to charge an iPhone or a Samsung phone at least 8-10 times. Considering that the battery of a smartphone should last at least 1 day under continuous use, then we can say that the solar power bank should last around 1 week.
However, if you use the external battery to charge multiple devices, then the charger won’t last as long. Consider if you are looking for a solar power bank for laptop or if what you want is a cell phone solar power bank. This will influence the decision of the battery capacity.
Roughly How Long Does a Full Charge Take?
As with the previous statement, the battery capacity determines the charging capability.
Solar power is a source of energy that varies according to climatological conditions. Therefore, establishing charging times is not an easy task.
However, based on recommendations from manufacturers, we can establish some charging range.
For instance, for a 20000mAh power bank, requires between 60-70 hours to charge (around 3 days) only using solar energy as a primary resource.
Another way to estimate this is to apply the following expression
Time to charge= (Solar power bank capacity) / (solar panel power)
If we are dealing with a solar power bank of nearly 10,000mAh and we have a 2W panel, then:
Remember that 5V is related to the voltage at which the battery gets charged and 0.8 is a factor referred to losses in solar energy into electrical conversion.
If you have access to a POWER OUTLET, use it. You could end up reducing charging times by 5-6 hours. Before taking any trip, fully charge your solar power bank by plugging it into an outlet, and use solar energy as a CONSTANT RECHARGE SOURCE while you are outdoors.
posted from Bloggeroid
Thursday, March 26, 2020
Hey Jude, Song by The Beatles
Hey Jude
Song by The Beatles
Hey Jude, don't make it bad
Take a sad song and make it better
Remember to let her into your heart
Then you can start to make it better
Hey Jude, don't be afraid
You were made to go out and get her
The minute you let her under your skin
Then you begin to make it better
And anytime you feel the pain
Hey Jude, refrain
Don't carry the world upon your shoulders
For well you know that it's a fool
Who plays it cool
By making his world a little colder
Na-na-na, na, na
Na-na-na, na
Hey Jude, don't let me down
You have found her, now go and get her (let it out and let it in)
Remember to let her into your heart (hey Jude)
Then you can start to make it better
So let it out and let it in
Hey Jude, begin
You're waiting for someone to perform with
And don't you know that it's…
posted from Bloggeroid
Tuesday, March 24, 2020
Copper kills bacteria and viruses. Why aren’t our surfaces covered in it?
Civilizations have recognized copper’s antimicrobial properties for centuries. It’s time to bring the material back.
These ancient civilizations were referring to COPPER, a material that cultures across the globe have recognized as vital to our health for more than 5,000 years. When INFLUENZAS, bacteria like E. coli, superbugs like MRSA, or even coronaviruses land on most hard surfaces, they can live for up to four to five days. But when they land on copper, and COPPER ALLOYS LIKE BRASS, they begin to die within minutes and are undetectable within hours. “We’ve seen viruses just BLOW APART.” says Bill Keevil, professor of environmental healthcare at the University of Southampton. “They land on copper and it just degrades them.”
No wonder that in India, people have been drinking out of copper cups for millennia. Even here in the United States, A COPPER LINE BRINGS IN YOUR DRINKING WATER. Copper is a natural, passive, antimicrobial material. It can self-sterilize its surface without the need for electricity or BLEACH.
Copper BOOMED during the Industrial Revolution as a material for objects, FIXTURES, and buildings. Copper is still widely used in POWER NETWORKS—the copper market is, in fact, growing because the material is such an effective CONDUCTOR. But the material has been PUSHED OUT OF many building applications by a wave of new materials from the 20th century. Plastics, TEMPERED GLASS, aluminum, and STAINLESS STEEL are the materials of modernity—used for everything from architecture to Apple products. Brass DOOR KNOBS and HANDRAILS WENT OUT OF STYLE as architects and designers opted for SLEEKER-LOOKING (and often cheaper) materials.
Now Keevil believes it’s time to bring copper back in public spaces, and hospitals in particular. In the face of an unavoidable future full of global pandemics, we should be using copper in healthcare, PUBLIC TRANSIT, and even our homes. And while it’s too late to stop COVID-19, it’s not too early to think about our next pandemic.
The benefits of copper, quantified
We should have seen it coming, and in reality, someone did.
In 1983, medical researcher Phyllis J. Kuhn wrote the first critique of the disappearance of copper she’d noticed in hospitals. During a training exercise on hygiene at Hamot Medical center in Pittsburgh, students SWABBED various surfaces around the hospital, including toilets bowls and door knobs. She noticed the toilets were clean of microbes, while some of the fixtures were particularly dirty and grew dangerous bacteria when allowed to multiply on AGAR PLATES.
“Sleek and shining stainless steel doorknobs and PUSH PLATES look REASSURINGLY clean on a hospital door. By contrast, doorknobs and push plates of TARNISHED BRASS look dirty and CONTAMINATING,” she wrote at the time. “But even when tarnished, brass—an alloy typically of 67% copper and 33% zinc—[kills bacteria], while stainless steel—about 88% iron and 12% chromium—does little to IMPEDE bacterial growth.”
Ultimately, she wrapped her paper up with a simple enough conclusion for the entire healthcare system to follow. “If your hospital is being renovated, try to retain OLD BRASS HARDWARE or have it REPEATED; if you have STAINLESS STEEL HARDWARE, make certain that it is disinfected daily, especially in critical-care areas.”
Decades later, and ADMITTEDLY with funding from the Copper Development Association (a copper industry trade group), Keevil has pushed Kuhn’s research further. Working in his lab with some of the most feared pathogens in the world, he has demonstrated that not only does copper kill bacteria efficiently; it also kills viruses. (In 2015, he even demonstrated this phenomenon with a precursor to COVID-19, coronavirus 229E)..”
ABOUT THE AUTHOR
posted from Bloggeroid