The energy costs of electricity and gas are dramatically high when a person is in the initial stages of cooking when the water has not boiled. You can devise a cheap and simple pressure cooker with ease by covering the cooking pan or vessel that you are using by covering it with a lid to increase the pressure which lowers the boiling point. I have discovered that covering food reduces the energy cost by half.
Yes, this has been a tried and proven method for saving on time and on energy whether it may be gas or electricity that is used for the cooking process. It's very convenient that you put whatever you need to cook in the pressure cooker and cover it set your timer and leave it to cook. Under pressure, whatever you are cooking will be ready in a significantly smaller period of time compared to the non-pressurized way of cooking. One drawback of cooking with pressure is that when the cooking process is done you will have to let the pot cool a for a while, losing valuable time before you may open, if not the contents would explode and cause harm to come to you.
That is so true, @remnant . Covering the cooking pot/vessel with a tight lid does speed up boiling/cooking time and may reduce gas consumption by half. The heat also helps ensure that the food is cooked well and evenly. I only use the real pressure cooker for beef or hard meat parts like knuckles or legs. For everything else, I use the right size of cooking pot with the matching lid. I don't have a deep fryer at home but I can achieve the same level of frying by simply covering a pot with a see-through glass lid while cooking. I also end up saving on cooking oil with this method.
We have rice cooker, LPG stove. We are using rice cooker when we are running out of gas. We use LPG stove when there is no electricity. And these two sets of cooking equipment aren't available or we can to save money on LPG, on electricity, we have a dirty kitchen. This is where we use our cooking steel pot or caldron enough to cook rice for a family of 7 members. We use an open fire to cook our food. This caldron has a lid and handle with enough fire could boil the rice for 15 to 20 minutes and it has to take another 5 to 10 minutes to complete steam the rice and be ready to be eaten.
It’s not only in boiling water that you need the lid of the pan or pot. When I am frying, the moment I pour the cooking, the lid is already in place so the heating of the pan is faster. And when I place the meat for frying, the cover is also in place all the time which makes cooking faster and not messy (sometimes the oil would spatter). Another way to save on fuel of the stove is to control the fire – use medium fire when the cooking is halfway and use low fire when nearing to finish your cooking. You only use high fire at the start because when the pot is already boiling then there is no need for high fire.
I often found that when shallow frying say fish, if I cover it immediately then it gets boiled/steamed rather than fried, something that does not get me the desired results. The best way is to remove water from the fish thoroughly, put the flame on the highest and then put fish in hot oil. That way it doesn't stick to the pan nor does it break, gets evenly cooked and doesn't splutter oil. It also saves on the longer cooking time. Closing the lid while frying encourages water droplets to fall on your fish and hence it results in boiled fish and oil splutter and longer cooking time.
I have never tried to pressure cook myself but always was interested in the product and the phenomenon for quite a while. As many have already said it can make cooking a lot more easier and is a cheaper option when it comes to cooking. The cost of the pressure cooker itself might seem a bit high price but it will pay off itself in time.