With the global population at a steady rise, there is uncertainty about our ability to provide resources for the future generation. Food, water and energy are necessities. We shall be focusing on the energy part. Cooking gas is the main fuel used today to power cookers.
Being a product of an unrenewable resource, there are fears that it may eventually run out. Apart from that, it doesn't come for free--we have to buy it. This is why we should try to reduce our daily usage of cooking gas. For both environmental and financial reasons.
I made a pot enclosure with the purpose of fixing the energy waste crisis, especially in the kitchen. When we cook, not all the energy is used to cook the food. Some is given off, hence, wasted. This pot enclosure made out of fabric and plastic bags is a tool to use in your kitchen when you want to save cooking gas. It is perfect for simmering. Once food in a pot has been on the fire for a while, the fire can be switched off and the pot put into this pot enclosure, away from the fire. This pot enclosure is capable of trapping the heat in, preventing it from getting lost to the outside environment. The trapped heat further cooks the food and keeps it warm even in the absence of external heat. This method of cooking in the enclosed space with trapped heat is more cost-efficient and at the same time, keeps food hot longer.
With no mechanical parts or grand cost, this easy object can be made in less than thirty minutes with little sewing skills. Even if you clueless at hand-sewing, a sewing machine will do the job.
The pot enclosure operates using simple physics. It uses layers of insulation to keep heat trapped. A plus is you also get to reuse plastic waste in the process. It will cost you close to nothing to develop it and begin saving money and energy in your home.
Step 1: What You Need.
To get started, gather the following.
-Black fabric and white fabric. (Can be bought in a fabric shop or online stores. Which ever type you use is up to you, just make sure it's heat resistant and with little air spaces. I think leather will be best. You can use whichever one you have though )
-A pair of scissors.
-Needle and fishing line or thread. (If using fishing line, get that which is 0.25mm thick.)
-plastic bags. (No need for new ones. The used/old ones will do just fine.)
-Chalk (Any color which will be visible on your fabric .)
In case of the fabrics and plastic, the quantity you choose will depend on the size of the enclosure you are trying to make. How big do you want it?
Step 2: Measuring and Cutting.
Considering you are making this pot enclosure for a particular pot, you will have to measure the size of the pot before commencing. Get a ruler and measure the diameter of the pot's interior. With that done, it is time for a little math. Multiply the value of the diameter by three. In my case, I got the diameter as 20cm. 20×20=60cm. This value will be the dimensions (both length and width) I will use when cutting my fabric.
Spread the black fabric on a flat surface. Spread it out and smooth all wrinkles. With the previous multiplication value in mind, sketch lines on the fabric using the chalk. With equal length and width, you should draw a perfect square. This lines are just there to aid you during the cutting process.
Grab your scissors and begin cutting.
Purpose of fabric: This black fabric shall serve as the interior layer of the enclosure. It's well known that black traps heat, reason why we are using it not another color.
Step 3: Add Plastic Bags
Plastic bags should be lightly filled with air and knotted. Not too much air, just a little. Then line them on the black fabric in a square-shaped manner. They need not cover the entire fabric but they should be centralized. In the absence of plastic bags, bubble wrap is an alternative.
Purpose of plastic bags/ bubble wrap: Bubble wrap has little air bubbles, making them a great insulating material. The plastic bags are mildly inflated to make it as much of an insulator as the bubble wrap. This will form the central part and is essential to keeping heat in.
Step 4: Cover and Sew.
Cut out some of the white fabric. It need not be same dimensions as the black fabric. It will still be fine if it's smaller and just enough to cover the portion with the plastic bags. Get your needle and fishing line or thread or sewing machine and sew the materials together. Using fishing line is preferable over thread because it is stronger and almost invisible.
Purpose of white fabric: If heat ever permeates the black fabric layer and that of the plastic bag, this will reflect the heat back into the enclosure which in turn gives the heat back to the pot. Simple physics.
Step 5: Forming the Point of Entry.
This is still a rectangular piece of material. We have to make it pot-shaped and create a point of entrance and exit if the pot. We will do this using pleats, just like those on a skirt. Thread a needle (Length should be same as that used in earlier measurements). Hold the fabrics by the edge and stick in the needle. Giving four inches of space as you repeatedly stick and remove the needle all round the fabric. Pulling should drag the edges together around the central point, hence forming somewhat of a sphere( View picture to see what I mean)
Cut needle and tie knots on either side. When you pull each side of the thread in opposite directions, it closes like the aperture of a camera. It can be opened by tugging at the centre
Step 6: Ready for Use.
It is now ready for use. Simply remove a boiling pot from the fire and place in the enclosure. Close tightly. You'll notice that the pot's content remain getting cooked due to the enclosed heat. In this closed space, the food or whatever gets simmered by the heat for longer and remains hot.
*Note: Effectiveness of heat entrapment is directly proportional to the absence of any air spaces once the enclosure is sealed.