In order to play its role as a local authority who is the bulk distributor of electricity, NMBM takes several actions in analysing the current situation and forming action plans to face the challenge of climate change and rising greenhouse gas emissions. In this context NMBM developed the State of Energy Report, the Climate Change & Green Economic Action Plan, the IEP and a Municipal Energy baseline report.
Furthermore, NMBM introduces the Municipal Energy Management System and formed a Municipal Energy Management Group to systematically and continuously monitor, analyse and improve the municipality’s specific energy consumption by facilitating energy efficiency and energy saving measures.
Some of the initiatives are:
- Applying for EEDSM grant fund. Through the 2020/21 EEDSM fund NMBM replaced 1140 streetlight fittings at the N2 from 400W HPS to 180W LED. The project has a simple payback time of 2.8 Years and energy savings of 60%.
- Installation of smart meters at municipal buildings to monitor electricity consumption online and develop action plans.
- Traffic lights were changed: 14 000 bulbs replaced 75/55W replaced with 11/10W LEDs
- High mast lights: 400 Watt LEDs to replace the 1000-Watt HPS High Mast Lighting. Consumption reduced by 65%
- Streetlights: current process where thousands of old HPS lights have been replaced with more efficient LED lights.
The Department of Mineral Resources and Energy gazetted the 8th December 2020 an amendment to the National Energy Act, 1998, regulating the mandatory display and submission of Energy Performance Certificates (EPC) for buildings. This applies for municipal buildings net floor area of over 1000m2 as well as private owned buildings over 2000m2, that fall into following categories:
- A1, Entertainment and public assembly
- A2, Theatrical and indoor sport
- A3, Places of instruction
- G1, Offices
This amendment makes it mandatory for owner of those buildings to conduct an energy audit and to display an Energy Performance Certificate, issued by a SANS-accredited body.
For more information please also visit the SANEDI website:
3.1 Electric appliances
Electricity appliances also play a very important role in reducing electricity consumption. 1994 the European Union established an energy consumption label, which rates the energy efficiency of appliances from A (most efficient) to G (least efficient). As the companies produce each year more efficient appliances there are now also products with the energy efficiency class up to A+++ available.
Let's take the fridge as example. Often people run their fridge until it's not working anymore, which is good but not energy efficient and maybe also very expensive.
Old fridges often have the energy efficiency class C (or worse) and an average fridge with 120l cooling and 50l freezer consumes about 450kWh per year. At an electricity price of R2/kWh the electricity for this fridge will cost you R900 per year. A modern fridge with the same size and a Class A+++ will consume 130kWh/a, which is R260. That results in a yearly electricity saving of R640. When you got an old fridge or want to buy one, you should pay attention on the energy class, as it can save a lot of money each year. As the appliances get normally more expensive with higher energy efficiency classes one should compare not only the purchase price but should also take the running expenses into account.
The past years there was a huge development in the light industry. For a view years the compact fluorescent lamps (CFL) were called energy saving lamp and one should change the ordinary light bulbs with these to save money and energy. It is still a valuable solution compared to the incandescent light bulbs, but the past years a more efficient light has entered the market, the LED lights. The LED lights are available in all kind of forms, colours and different sockets.
They can even replace your fluorescent light tubes or halogen lights.
For example, a light bulb uses 50W, the CFL 15W and the LED lights use only 5W and produce the same amount of light (lumen). The life expectancy of those LED lights is also much higher than of a normal light bulb. Taking these advantages of a LED light into account the payback time of them is often less than 1 year.
Annual operating cost (based on R2/kw and 5hr operation per day)
15 000 - 20 000 hours
8 000 hours
= 4 years
1 200 hours
= 8 month
Yearly cost over life
3.3 Water heating
In a typical household the bulk of the consumed energy is used to head up water. The average hot water consumption of a person/day is about 30-50 litres. This includes showering, cooking, cleaning, dishes, etc. For a family with 2 kids this leaves you with a daily hot water consumption of about 150?litres. At?an electricity price of R2 this will cost you R470/month or R5,640/year. By installing a 200-litre solar geyser most of the electricity can be saved. A complete 200 litre system installed will cost you about R15,000 and assuming that you will only save about 70% of the so far used electricity this will give you a payback time of about 4 years. In many cases not a whole solar system has to be purchased and only solar panels are connected to the existing geyser (pump split system). If the old geyser is still in good conditions and well insulated this is a viable solution and can bring your payback time even further down.
The most common solution seen in SA is a Thermosiphon system, where the geyser is installed above the solar panel/tubes and the hot water circulates automatically. The left picture below shows a solar system for a flat roof. The right picture shows a pumped split system, where the geyser is inside the roof and also below the solar panel/tubes so a pump is required to circulate the water through the solar panel.