Questions about Energy Audits, Solar Power and LED Lighting

Solar power, Smart LED Lighting Solutions

Questions about Energy Audits

What is an Energy Audit?

An Energy Audit is a process requiring us to attach our unique Snitch Data Loggers to your DB board and measure your electrical data and measures daily kilowatt hours individually. Our process is unlike anything else because we combine the technical data with local weather data for your specific area.

For more info – Click here and visit our Services Page.

What does an Energy Audit (EA) cost?

The costs shown below are fully reimbursed back to you upon your acceptance of the quote produced from the EA.

Cost breakdown:

  1. R2500 – (1 to 20 line logger)
  2. R3250 – (21 to 30 lines – 2 loggers)
  3. R3970 – (31 to 40 lines – 2 loggers)
  4. R4500 – (41 to 50 lines – 3 loggers)

The above costs are based on the number of circuit breakers located within your DB board.

Example 1 – if your DB board has 10 or less circuit breakers or switches, then its a 10 line logger required.

Example 2 – If your DB board has between 11 & 20 circuit breakers, then its a 20 line logger required.

50 Circuit breakers or more will be quoted special rates on a case by case basis, (further discount will be given based on approval.) Energy audit costs will be Fully Refunded should you proceed with any option.

Do I need an Energy Audit to correctly size my Solar Power (PV) system for my home or building?

Yes ideally, the only time we cannot do an Electronic Energy Audit is if your home is still being built, we will then simulate one based on your current situation. The advantage is that all our Solar (PV) Solutions are modular so we can add on if needed.

Questions about Solar Water Heating

What important questions should I be asking Solar Water Heating Specialists?

Questions you should be asking Solar Water Heating specialists, installers or sales consultants before making a decisions about your installation.

  • You can ask if the solar company is registered with the Sustainable Energy Society South Africa or (SESSA)? We also advise checking to see if the are qualified to perform work within the Solar Water Heating industry.
  • Ask if the products they are proposing to install have the South African Bureau of Standards (SABS) approval?
  • We suggest that if references are not visible on a website, that you ask for existing client references or testimonials.
  • If the person you’re speaking to is a Supplier & Installer of various solar solutions, ask them if they are qualified Water-smiths or have relevant solar experience? Do they outsource the job or is it all done in-house?
  • If information is not available on their website, ask for more details or an explanation about the product or solution being proposed. Questions about the dimensions, type of thermal-collectors, tank insulation, plumbing quality and workmanship as well as the guarantee / warranty period associated with the product or solution.

Can the Solar Water Heating system be installed in frosty or low temperature areas?

Solterra mostly use our Nobel Systems which are indirect Solar Water Heating systems. The indirect system involves having a solution which is a mix of glycol, food-based anti-freeze and corrosion inhibitors flowing through it to avoid damaging the collectors, such as freezing and cracking. The water in the solar storage tank is heated by a heat transfer-er or heat ex-changer.

How often does the Solar Water Heating system require maintenance?

For optimal performance and savings, we recommend that you have your solar geyser serviced once a year. Our high quality Nobel Hyperion solar geysers come with a standard 10 year warranty, we extend this to 15 years based on a signed Service Agreement.

What happens during the winter season?

Our NOBEL Solar Geysers Systems are between 90% & 95% efficient, this means that even with little to no sunlight, the irradiation and UV factors are still enough to cause the Thermal Panels to heat the water in the system as they also rely on Solar radiation. If the water is not hot enough, the 2 Kw electric element will kick-in when the water drops 5º C below the set temperature, or you can manually override the system with a Geyser-wise Control Panel. In the end, it means more savings. We can give you a clearer picture on the amount of savings you can expect during winter months during a consultation.

Is a timer switch necessary for my Solar Water Heating system?

For maximum efficiency of your system, we recommend having a timer switch installed. This will help the system make full use of solar radiation during sunshine hours and ensures availability of hot water during bad weather.

What are the environmental and financial benefits of having a Solar Water Heating system installed?

Most of the electricity in homes is currently generated by burning fossil fuels, 40% of which is used for heating water. Solar Geysers use solar energy or solar power & irradiation, this reduces your carbon footprint as well as decreasing the demand from the South African power grid. In simpler terms, installing a solar geyser is akin to removing the carbon footprint of a small car.

How long does a Solar Water Heating system or Geyser last?

A high quality well installed solar water heating system such as our NOBEL Geyser, has a life expectancy between 15 to 20 years, and we recommend you have our annual Service Agreement.

Will my Solar Water Heating system work on cloudy days?

A 2 Kw electrical backup element is standard in our Solar Geysers. This will automatically switch on to heat your water during overcast or cloudy weather, when the thermostat detects more than a 5º C drop, it will revert to using the element to heat the water to the preset temperature.
The temperature of the hot water we take a bath or shower in, is between 41º C to 43º C while the thermostat is usually set at 55º C. Any sun shining through will heat the water to the preset temperature, reducing your electricity costs.

How do I know what size Solar Water Heating system I need?

As the water heating needs varies from household to household, we recommend that our specialists have an on-site consultation to determine your particular requirements. We have to make sure that the system is large enough to hold the capacity of hot water equivalent to a 24 hour need based on your household’s requirement. A smaller system would defeat the purpose of reducing electricity bills as more Eskom power will be used to heat the water.
We generally size Solar Geysers by way of 50 L of water per person per day, so for a family of 4 people, a 200 L geyser is required.

How hot will the water get using Solar Power?

An efficient solar geyser can reach up to 100º in summer and around 45º in winter. Our thermal panels are high pressure up to 400 Kpa. Our solar geysers are designed to ensure maximum efficiency throughout the year. The temperature control panel we suggest to be set at 55º so that the water does not get too hot. Very hot water is a safety hazard but also is a waste of energy.

Is there an Eskom rebate on your product?

No, this rebate fell away some years ago. All of our products are SABS approved.

Does the system have to be installed on the roof?

No. If your installation is to be installed on the roof, this is known as a Thermosyphon System. We supply and install systems for all roof-tops. A split or pumped system is for (in-roof) solutions, this requires an additional 12V TDC Solar Pump as part of the installation, (it comes with its own small PV panel and battery backup so not grid dependent.)

What is a Retro-fit?

A Retro-fit system is when we convert an existing ‘electric geyser’ by way of a modification into a solar heated system, this is cheaper than a Complete Solar Geyser solution. We only recommend this for electric geysers that are 2 years old or less due to the fact that they were not designed as solar geysers are and the pressure and efficiency is very different.

Do you install tube systems?

No, the tube system (also called the Evacuated tube system) was specifically designed to cater to the European climate, where the weather is colder than the weather in South Africa. This brings a new set of problems like the system losing balance, uncontrolled temperature and so forth which reduces the life expectancy of the system, with hail being the most obvious threat.

Do you install direct systems?

Yes, this is dependent on your geographical area. The direct system involves heating actual water that is being used within the geyser, the water flows directly through the collector in the tank instead of a Heat Transferor. The main reason we do not install many of these is due to water quality in certain areas of South Africa which are substandard. Poor quality water results in building up lime and calcifying the inside of the collector, eventually blocking pipes.

Questions about Solar Power (PV)

Can I use solar power to provide electricity for my entire home?

Yes, the only restriction being the space needed for solar power generation, battery backup and surplus recovery. Each (PV) panel is 1.8m long x 1m wide and weight 21 kilograms. So we do a site visit to ensure that enough space is available for a complete solar power system.

Do you have 3 phase systems on offer?

Yes we can supply 3 phase systems.

Do I require batteries?

You do not need to have batteries on a Smart Grid / Grid-tie System, this is for daytime generation only. Hybrid Systems will require a battery bank depending on your current requirements which are determined by way of an Energy Audit. Complete Island Systems are 100º off-grid and batteries are required in this instance. We can design different types of systems to cater to every need from Small Residential to Large Businesses, Hotels and Game Farms.

Can a home using this system be completely independent?

Yes, however it will not may not be financially beneficial to start with a Island System, we recommend a Hybrid System unless there is no Grid Power in the area.

Can you feed back into the grid?

Yes we have been able to feed back into the grid in some areas, this is only available to SSEG registered clients, applications can take up to 6 months to be approved. We would need to submit the application along with our Energy Audit and Data recordings.

What is the payback period for Solar Power?

Payback periods are determined by a number of factors. Solar Efficiencies are normally factored into the calculation and can be up to 5 years. The Photovoltaic (PV) system will also vary from 3 to 10 years depending on your current electricity usage and the geographical area you live in. There are escalating tariffs which will influence the payback. Most of the grid-tie systems however show an average ROI of around 3 to 5 years.

Questions about Heat Pumps

Can the Heater Pump be installed inside the roof?

No, heat pumps require a constant source of ambient air to work efficiently, they are also noisy and require maintenance, and gas refilling is part of this maintenance.

How is the geyser water heated by the heat pump?

Cold water is pumped into the heat pump through copper pipes from the geyser, the pipes which go back to the geyser carry the hot water. This continuous flow keeps on going until the water in the geyser rises up to the preset temperature of 50º C to 55º C.

Is the heat pump a replacement for the water geyser?

No, the heat pump’s function is to heat up the geyser where the water is stored. We only advise a heat pump installation if 1 of 2 conditions are apparent:

  1. No space for any Solar Geysers or Thermal Panels
  2. More than 1200 L of water needs to be heated at any one point, (best for large Hotels and Guest Lodges.

What % of savings in electricity costs can I expect using a heat pump?

The heat pump can save up to 27% in monthly electricity bills, this savings would have been paid to Eskom. Various regions will change and savings will also vary. (Solar Geysers will save up to 60%) so depending on your requirements, there are circumstances where Heat Pumps are the only option. Solterra – Cape Town will help you by way of a site visit.

Questions about Smart LED Lighting

What does LED stand for?

LED is an acronym for light-emitting diode.

How long do LEDs last?

LEDs are known to be very long lasting lighting products, typically lasting up to 50 000 hours. This is a longer life span than the incandescent (up to 50 times), 20 – 25 times longer than a halogen, and 8 – 10 times longer than your typical CFL. This means being used for 12 hours a day every day, an LED can last up to 11 years, and can last up to 17 years if used 8 hours or less per day.

Where can LEDs be used?

They can be used anywhere.

What are the advantages of LED compared to others?

To name a few, LEDs use less electricity and have very long lifecycles, they emit no UV radiation, and produce little heat. LEDs also contain no hazardous material like mercury and are shock-resistant, they work effectively in all weather conditions.

Is it worth the higher cost of LEDs compared to other lights?

Yes. As with any type of new technology, initial quality production costs are typically high. However, with increasing demand for LEDs, its prices have dramatically dropped and will continue to do so as demand keeps increasing. A point to keep in mind is that although the upfront cost is high, LEDs use up to 90% less electricity and are extremely durable. Factoring those into the equation, the upfront cost is quickly turned around into savings within 6 months to a year – this depends on the quantity of LED lamps you require.

Do LEDs produce enough light for me to replace my current bulbs?

Yes. LEDs available in the market now are replacing the incandescent bulbs of up to 100 Watts and more specialized LEDs are now available to replace high wattage ones as well. LED’s vary from the average 3 watts upwards. A GU10 or ‘down-lighter’ come in various white shades and cast light up to an angle of 100º, the average lumen is from 250 lumens upward.

Are LEDs environmentally friendly?

Yes. LEDs need less electricity thus reducing power plant emissions that typically run on fossil fuels. As opposed to CFLs, LEDs do not have mercury. LEDs also save up on solid waste as you don’t have to throw away 50 equivalent incandescent lights and produce much lesser heat than their counterparts. The US Department of Energy estimates that the increased adoption of the LEDs in the next 15 years will reduce power produced for lighting by 62%, prevent 258 million metric tons of carbon emission, reducing the number of power plants by 133 units. This is no different in South Africa.

Can LEDs be used in dimming systems or used with dimmers?

Yes. Most LEDs are listed as being dimmable, however some systems work with LEDs better than others. We recommend speaking to one of Solterra – Cape Town experts or call us for a site visit, we will best advise you on what there is in the market for your individual requirements.

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  • Hybrid pv solution with underfloor heating and a 200L solar geyser working perfectly.. Clients are #savingmoney every month. Well done #solterracapetown installations team.