Urn Jacket - What the best dressed Urns are wearing.

I work at a school where coffee and tea are available all day. It occurred to me that a lot of energy is being wasted keeping the urn on all day.   I carried out an experiment using first one layer and then two layers of batting in an urn jacket.

On 6 trials the urn used an average of 0.280kW/Hour, with one layer it was 0,215kW/h and 2 layers and a hat brought it down to 0,198kW/h.   This is a saving of 37%.   The saving is not so much in the initial boiling of the urn but in it maintaining its temperature.

The urn has to be fitted for size and holes for handles, controls and outlets.   I used velcro to connect padded strips above the handles and at the front top and bottom.   The eyes are just for fun.   The hat is a circular cushion with a hole in the middle, filled with polystyrene beads which help it settle down on the slightly domed surface of the lid. An elastic band was initially used to keep the jacket snug but is no longer necessary.

Meringue baskets

(using a solar cooker only)
Meringues cooked in a solar oven are superior to those cooked in a conventional oven. They stay fluffy and white and will impress all your friends. Meringue baskets can be filled with ice cream, cream, berries or anything that your imagination can suggest. These quantities make 3 – 6 baskets depending on size.

3 egg whites
1 cup sugar or castor sugar
1tsp lemon juice
Beat egg whites with one teaspoon of the sugar until stiff. Add the rest of the sugar gradually beating well in between. Use a piping bag to form baskets onto a baking tray which fits into your solar cooker. Start with a circular base and then pipe the sides on top of the base. Make meringue triangles for garnish. Cook in the solar cooker facing the sun for two to three hours. Fill with ice cream or other filling of your choice.

The biogel stove

The Biogel stove
Biogel stoves became very popular during the period of load shedding in South Africa. The fuel is an ethanol gel which is a renewable energy source ie it is not a fossil fuel. Most biogel stoves are very simple, having a reservoir for the fuel, an adjustable vent and a stable base for a pot to rest on. The most popular are double plate stoves which means one can cook two separate foods at once. At the time of writing the stoves and the gel were available at Pick and Pay stores.
Advantages of a Biogel stove
The stove has a wide flat base and can’t be knocked over.
Because the fuel is a gel, not a liquid, it can’t spill.
The vent controls the amount of air getting to the fuel so the stove can be adjusted for low, medium or high cooking.
There is no unpleasant smell, just a clean alcohol smell.
The stove is portable and easy to carry.
Disadvantages of a Biogel stove
Once the food is cooked, if all the biogel has not been used up, it can’t keep in the stove as it dries up. It is necessary therefore to know exactly how long you want the flame to last for and use the appropriate amount of gel (see table below)
Biogel fuel at present is more expensive than paraffin and so is more often used as a back up for electricity cuts in urban areas than as a normal method of cooking in poorer or rural areas where the increased safety would cut down the number of fire related accidents.
Table showing amount of Biogel to use for various times of cooking (measuring cups were used to measure gel)
Volume of Gel                                          Time of burning on high (minutes)

100ml	27
200ml	54
300ml	81
400ml	108
500ml	135

The Solar Cooker

The solar cooker I use is a Sunstove, available from Margaret Bennett . e mail at sunstove@iafrica.com.



This method of cooking is the only one which is totally free. It is extremely easy. Place the food in a black pot, place in the solar cooker which is facing the sun or facing north if you are going to leave it for a long time.
The Sunstove comes with a pot and an instruction booklet, including recipes. It is ideal for one pot cooking, stews, vegetables, rice, pap, mince dishes. It is not suitable for dishes requiring rapid boiling, eg pasta, frying or baking (except meringues)
A black pot is preferable, but not essential. The sunstove cooks even if there is only 30 minutes of sun per hour. Food needs to be put in the sun before 10am as that is the best time for cooking. It is also possible to place the food in the sun before work and leave the sunstove facing north. It will be ready by 2pm but still warm by 4pm. It might just need a bit of reheating later in the day.
Advantage of a solar cooker

1. Free energy
2. It is light and so portable and can be moved to where the sun is, or taken camping etc.
3. It is almost impossible to burn food.

Disadvantages of a solar cooker

1. The cooker only works when there is enough sunlight, therefore not at night and not in the rain. It cannot be used as the only source of cooking. It can only be an additional source of cooking and will always require a back-up. However, when it can be used it saves electricity or wood or other fuel.
2. Food left unattended for long periods can be stolen. (Of course if there are grannies in the community they can sit near all the solar cookers and guard the food and cookers)

General Guidelines

1. The sunstove is designed for a family of 4. It can take more than one pot but if cooking for a larger number of people it will be necessary to use more cookers.
2. For cooking fresh vegetables it is not necessary to add water. Food will cook in its own juice.
3. Food must be placed in the sun before 10am in the morning for best results.
4. (From Sunstove 2000 Booklet)(2)

a) You will need twice the normal cooking time or a bit longer
b) Stews and casseroles use less water.”
g) food will cook quicker in 2 smaller pots than one big one. Don’t leave a lot of airspace above your food.”

1. The pots will get extremely hot and the use of a pot holder or oven gloves is necessary for removing the pot from the solar cooker.

Temperatures reached by the Sun stove

Dec 29 2009                                    

Partly cloudy, Max 26°C                         
Time           Temp °C                                                                           

9.00	40
9.30	50
10.10	90
10.55	120
11.20	120
12.00	120

These were my two extremes. When there was 50% cloud cover the stove reached a maximum of 95°C, 25% cloud cover it reached a maximum of 110°C. Cooking with more than 50% cloud was not very successful and another source had to be used to complete the cooking.

The Hot Box

In days gone by farmers’ wives knew that if you heated up porridge to boiling point for five minutes before bed, it would continue cooking if the pot was placed in a box and completely surrounded by hay. The next morning there would be a
warm breakfast. They called it a Hay Box. This is the basis of the Hot Box, also sometimes known as the Wonder Box. It relies on the principle of insulation. Food heated through for five or ten minutes and then well insulated, will continue
to cook as the heat is kept in.
At the simplest, place the pot on a dish cloth on the middle of a blanket. Fold the blanket around and over the pot and put it in a corner out of the way. The Wonder Box consisted of a specially shaped cushion inside a box and was  marketed by various charities. Any good insulation can be used in a Hot Box, even balls of crumpled up newspaper.
How to use a Hot Box for cooking.
Use the smallest pot that will take the amount of food you are cooking. The fuller the pot , the more efficient the cooking. Any source of heating can be used:- open fire, biogel stove, gas, paraffin or electricity. Heat the food and
enough water in the pot with the lid on and allow to boil for 5 or 10 minutes. Switch off the heat and place the pot upright in the box so that it is surrounded by the insulation or cushion. Leave for the appropriate amount of time (at least one and a half hours but it will continue to stay hot for up to 10 hours).

Recipes

Rice
Boil 2 cups of water and 1tsp salt and a stock cube. Add one cup of rice and allow to boil for another 5 minutes with the lid on but allowing a small gap for steam to escape. Place in Hot Box for an hour and a half.

Mielie meal
Use the quantities of meal and water you would normally use for the consistency you require. Boil for 5 minutes and then keep in the Hot Box for at least an hour or until required.
Chicken and Lentil soup
Add 4 cups of water to a chicken carcass, 1 tsp salt, 1 chicken stock cube, 1 cup lentils, a chopped onion, chopped or grated carrot or any vegetables of your choice. Boil for ten minutes then place in Hot Box for at least 2 hours. Can start
it before work and come back for supper. Remove the bones, scraping off any chicken still adhering to them. Liquidise if you prefer a smoother soup.

Foods that can be cooked in a Hot Box
The Hot Box is ideal for foods that cook slowly. It is excellent for rice, stews, one pot meals, dried legumes, vegetables,
mealie meal, soups. It works well at keeping most things hot and is ideal for transporting a hot dish for eating with friends. It is not suitable for foods that need brisk boiling like pasta.

Simple ways to save power.

We are all aware of the fact that the pot or pan is not hot enough as soon as we switch the hot plate on. It takes a little while for the plate and pot to heat up. In the same way, it takes a little while for them to cool down so if we switch off the power about 5 minutes before the food is cooked, it will still continue cooking in the hot pot on the hot plate.
· Use the kettle sparingly. A kettle is rated at about 2 kilowatts. Boil only enough water for your needs. If you are making one cup of coffee, boil one cup of water. This reduces the amount of time the appliance is working. Another option is to use a thermos flask or pump pot. Boil a full kettle and then pour any unused boiling water into the pump pot. For the next two hours you can use the water for making coffee or if you need it really boiling for tea, pour it back into the kettle and it will take much less energy to heat it up the last couple of degrees.
· Use the microwave instead of the hot plate as often as possible. Most food cooks faster in a microwave.
· Other options are a pressure cooker (which cooks faster because the high pressure enables the temperature to get much higher) an electric frying pan or steamer, where different foods can cook at the same time by stacking up on top of one another.
· On an electric stove top, use pots and pans with flat bottoms to maximize surface area and use a hot plate the same size as the pot.
· If you have to use the oven, make sure the seals fit properly to reduce heat loss. Test by closing a piece of paper between the door and the oven. If the paper slips out, you could be losing a lot of heat. Replace the seal to avoid wasting energy and money.
· Cook more than one dish in the oven at a time or one pot dishes on a stove top.
· Consider cooking in bulk and freezing, using the microwave to heat the dish.
· Thaw food overnight in the fridge rather than in the microwave.
· Keep the lid on when possible to reduce heat loss
· Dishes requiring browning in an oven eg macaroni and cheese use a lot of electricity just to get the cheese topping browned. Five minutes under a TV grill will give the same result with far less energy consumption.









Macaroni Cheese browned under a TV grill

• It costs almost the same to buy a roast chicken from most supermarkets as a fresh one. You save not only the electricity that you would use to cook it, but also the human energy you would use.
• Use insulation. We are so used to the concept of warming up food quickly in a microwave that we no longer try to keep it hot. Any insulating material wrapped around a pot or dish will help keep it hotter for longer. Examples are – newspaper, corrugated cardboard, blankets, packaging materials. The Wonderbox is an example of how food can not only be kept warm but continue to cook without the use of any electricity at all.