Q: What is solar water heating?
A: Solar Water Heating is a system for heating water using energy from the sun. Solar energy is collected by a panel that is connected by pipes to a hot water storage device such as a hot water cylinder.
Q:What are the benefits of solar water heating?
A: Solar water heaters can help save water heating costs by reducing the amount of electricity needed to heat water. By using sunlight to heat water instead of combustible sources or fossil fuel-produced electricity, fewer pollutants are being introduced into the environment. Solar energy is not affected by the current shortage of electricity and does not stop providing hot water during load shedding.
Q:How long do solar water heating units last?
A: The expected life of the equipment is 10 to 15 years. That said,they can last up to 40 years, but even if your solar water heating unit lasts a fraction of that time, it will have paid for itself many times over and will still be producing free sun power for your home.
Q: How much of my total hot water requirements can a solar water heater provide?
A: A solar water heater can provide between 50 and 90% of your total hot water requirements, depending on the climate and model of heater.
Q: If I replace a conventional geyser with a solar powered system, how much do I save on electricity consumption?
A: The electrical geyser uses 30% percent of your household's monthly electricity bill. Replacing your conventional geyser with a solar powered system will reduce that percentage of your electricity consumption by up to 70 percent.
Q: What happens in winter or on rainy days, when there isn't enough sunlight to heat the water?
A: Solar water tanks are well insulated and can keep water hot for a longer period of time. This ensures that there is always a tank full of hot water (and a back-up of hot water) in the early evenings/mornings provided the tank size is correct. An electrical back-up system is allowed on the programme provided it has a timer switch that ensures it does not operate during Eskom's peak demand periods.
Q: How hot can the water get?
A: Most solar systems heat the water to between 55-65º Celsius. You should have a timer installed with your system, as it has been shown that this will give you the maximum energy saving and ensure you have hot water in peak periods.
Q: What will the the total energy savings on my solar water-heating unit be?
A: Each piece of equipment has a different savings profile which depends on various elements such as geographical area, water usage profile, number of users and the size of the system. However, on a 200-litre system, the SABS average is 5.67 kW per day at 16MJ input power.
Q:Why is it important that a solar system be tested by SABS?
A: The specifications on solar water heaters focus on three main areas - quality, performance and safety. Testing systems verifies these requirements. As the payback periods are very important, it is vital that the solar water heater is of a quality that ensures the longevity of a system. The mechanical performance tests for hail, freezing and pulsation are conducted to ensure that the minimum quality standards are met. The performance tests are conducted to determine how well the system works, the safety test determines if all the safety requirements are met including electrical and mechanical safety criteria.
Q: Why is it important that solar systems get the SABS mark of approval?
A: The SABS mark takes the test report and adds an evaluation of the manufacturer's ability to consistently produce quality solar water heating units. This means that if the testing indicates a high quality, durable and safe solar water heater design, and the manufacturing quality audit indicates that the manufacturing facility can manufacture high quality products consistently, the SABS will allow the manufacturer to use the SABS mark.
Q: What is Eskom's involvement in the Shisa Solar solar water heating programme?
A: In order to reduce the growing demand for electricity, Eskom is embarking on energy efficiency and alternative energy programmes that promote energy savings on a large scale in order to mitigate system constraints. It currently offers a rebate on solar water heating units. The Shisa Solar programme includes this rebate and handles all the paperwork for you. With Shisa Solar, you also benefit from bulk discounts on solar water heaters, a narrowed-down selection of the best value solar water heaters (making your decision much easier), a list of pre-selected accredited installers in your area, and a free 5-year maintenance plan.
Q: Do I need to install a new geyser or can solar water heating units be added to the existing system?
A: Standard geysers are not designed to be utilised with solar collectors as they do not have sufficient inlets and their linings are often not designed to withstand the temperature experienced from solar energy.
The supplier should evaluate the existing geyser and, based on your needs, the supplier can evaluate the possibilities of using the existing system.
Q: Can I install the system myself?
A: The installation of a solar system, to qualify for the rebate incentive, has to be done by an approved installer. Even though the concept of the system may look simple, many areas can be damaged if the system is not installed by a qualified tradesman. Accredited suppliers register their installers and undertake to oversee the installations to ensure that they comply with the Shisa Solar programme, building regulations and other applicable legal requirements. Guarantees can also be lost if it becomes evident that someone without the correct technical expertise has tampered with the system.
Q: How much can it save in your typical electricity bill?
A: A geyser uses between 30% of the electricity used in a home. Typically taking overcast weather and usage patterns into account, 70% of this energy can be displaced by a solar system.