30 July 2019
Part 4: Technical Series on Energy Efficiency
Media Release: Part 4: Technical Series on Energy Efficiency
Issued George Municipality, 16th July 2019
Caption: Fezeka Mkhaza
George Municipality has launched a “ World of Tomorrow Festival 2019” to help increase public awareness of the importance of energy efficiency and the nine participating schools will present a 15 minute drama production. This initiative will take the message through children - to the homes of George residents - via an Industrial Theatre Competition which will introduce and explore the topic of “How do you mitigate climate change with energy efficiency.”
The dramas will highlight the changes individual residences and schools can make to become more energy efficient, which in most cases, will assist with curbing the effect of Climate Change – a global topic. This project has come about as a result of the George Electrotechnical department participating in the second year of a National Energy Efficiency Demand program, which includes funding provided by the Department of Energy (DOE) for public awareness around climate change and energy efficiency. The five electrical engineering interns will be assisting with the project and will each contribute a technical article on the topic.
Tickets are available for the Primary School Production (31 July 2019) and the High School Drama Production (1 August 2019) from Heather Stead on 072 369 3304 with tickets costing R30 for adults and R20 for learners . Limited tickets are on sale for attendance at the Gala Evening Production on Friday 2 August 2019, please contact Chantel Edwards-Klose on 044 8019111. Gala tickets are R50 per adult and R20 for learners.
Primary Schools participating are St Marys Primary, Holy Cross Primary, Kretzenhoop Primary, Hibernia Primary and Heidedal Primary. High schools are George High, McKinley Reid School, Rundle College and Thembalethu High.
The project is still looking for sponsorship of prizes in the form of a financial prize or energy efficiency product, and any individual or businesses that would like to contribute is requested to make contact with Heather Stead on firstname.lastname@example.org or 072 369 3304.
Our fourth writer in this series is Fezeka Mkhaza has a National Diploma in Electrical Engineering from Walter Sisulu University and she is busy with her BTech in Electrical Engineering through UNISA while working as an intern at George Electrotechnical Services, Planning department.
Energy efficiency in Cooking
Energy efficiency is the goal to reduce the amount of energy required to provide products and services. Improvements in energy efficiency are generally achieved by adopting a more efficient technology or by application of commonly accepted methods to reduce energy consumptions. Reducing energy use, reduces energy costs and may result in a financial cost savings. Energy efficiency can be applied in cooking, lighting, water heating, spacing heating, etc. This article will take a look at the pros and cons of various cooking options as well as an indication of the monthlybe addressing energy efficiency in cooking.
Ethanol is a safe, clean and more efficient fuel than paraffin with no odor. It is a sustainable fuel and the operating costs are comparable to the going rate of paraffin. The consumption is between 0.171 to 0.250 liters per hour with the monthly operating cost at R180 (R90 per plate based on average of 3 hours of cooking on each per day). The fuel is more efficient than electricity, but it cooks slowly. Methanol fuels are still an emerging market reliant on government funding where the security and affordability of the fuel supply is not guaranteed.
The stove is made up of a galvanized or stainless steel base with a ceramic, heat-absorbing liner. It comes with a stainless steel grill and a stainless steel pot spacer. The liner is heated by either wood or charcoal. Once hot, it optimizes the heat. The clay liner significantly reduces burning fuel required, which in turn reduces smoke emissions; decreasing costs, carbon footprint and health risks. It is much safer than paraffin or gas stoves and uses only 7-15 pieces of charcoal to cook a meal for a family. The stove costs approximately R450 and has a lifespan of 10 years or more. The stove is compact and mobile but cannot be used indoors as it uses “dirty” fuels that negatively affect air quality. If not used safely it is a fire risk. In terms of energy savings, when wood is collected there are no fuel costs. When wood or coal is bought: 4kg Wood = R12 and 4kg Coal is R40. When using wood, 4 to five pieces of wood cooks the meal for the whole family. Two packets of wood (2 × 4kg) for the week are enough at R24.
Gas is convenient, clean and relatively safe operating at a high heat which reduces cooking time significantly. LPG is a clean burning fuel and reduces indoor air pollution. LPG stoves quickly supply heat and work more efficiently than wood and paraffin stoves. The simple and precise regulation simplifies the cooking process and can save time. The monthly operating cost can range between R700 and R1 100 per month- approximately R125 per plate. There is a great need for widespread household education and awareness on the safe and efficient use of this technology. LPG tank management is difficult (storage, transportation) due to their sizes with LPG operating costs high more suitable for the middle- to high-income earning households. Gas is not regulated so the costs can vary over time making this difficult to include in a municipal
programme. Gas costs range between R16 to R21 per kg. In a two burner cook stove, 0.03kg is consumed when cooking for an hour which equates to
R0.63. When cooking with electricity for an hour the equivalent cost is R0.678 making gas slightly cheaper than electricity for cooking.
The stove is made up of a rugged plastic body, with space inside for several cooking pots. The Perspex lid allows light in, but traps heat within the cooker. The cooker works best with black pots.
The outlay costs for purchasing such a cooker is approximately R650 with no monthly operating costs, it is safe, requires little supervision and can cook an entire meal at once.
The solar cooker however relies on the sunlight for cooking which makes it difficult to use during winter months or rainy days and cooking takes significantly longer than conventional methods. The solar cooker is unlikely to provide all of the cooking services needed by households and it can be perceived as slow and unreliable. If one is cooking for approximately 1 hour a day, with 3000W 4 plates stove, maybe using 2 plates at a time you will use 547.5kWh per year. Therefore your saving with a solar cooker, is R214 per year when one cooks at off peak and R491 at peak during Low season
The hot box is an insulated cooker made up of two poly-cotton bags filled with expanded polystyrene (EPS) balls, into which a pot of food brought to the boil can be placed. The hot box uses the principle of thermal insulation to continue the cooking process without needing additional heat.
EPS is ecologically harmless, contains no chlorofluorocarbons (CFCs) and is fully recyclable. The hot box can be self-made with cardboard and newspaper, or straw, or bought for between R260 to R360 per bag. The method saves on cooking time and energy but can be only be used to complement another form of energy. In terms of energy savings since the pot is brought to boil and then inserted in the hot box you can work on the use of 0.375kWh (boiling one plate for 30 minutes) at a cost of R0.1695. If the hot box is used for three days a week the cost equates to R0.51.
Last published 30 July 2019