Frequently Asked Questions (F.A.Q) on Solar Hot Water
Below is a list of the common questions we are asked by customers when enquiring and considering the purchase of a Solar Hot Water system.We hope the list of these questions and answers helps your research on the viability of purchasing a Solar Hot Water system. Just click on one of the Subject Segments in the list below to be taken to the relevant FAQ's
he Clean Energy Centre are experts in Solar Hot Water and Solar Power, and we will do what ever is required to provide the right information you need to assist your decision. Please do not hesitate to Contact the Clean Energy Centre
to receive obligation free friendly assistance from a Clean Energy Centre consultant.
General questions on Solar Hot Water systems:
- It is quiet, uses clean energy and reduces electricity bills.
- It avoids the impacts of fossil fuel power stations such as greenhouse gas emissions and local air pollution.
- It can add value to your house, as more buyers are looking at energy efficiency and reducing the running costs of homes.
A solar hot water system converts sunlight into heat using special water pipe tubes or evacuated collector tubes and a hot water tank.
A solar power system uses silicon cells and light to produce electricity. A solar hot water system uses black pipes or evacuated tubes to collect the sun's clean energy to heat your water.
The science bit - When solar radiation or solar energy hits an object (you, me or a solar panel), the short-wave radiation is converted to long-wave radiation and this process creates heat.
In general, there are 2 types of solar panels for Solar Hot Water systems:
1. Glazed Flat Panels - simpler, less expensive, quite efficient.
2. Evacuated Tube - somewhat more efficient at capturing solar heat energy at low angles, but far more expensive.
Evacuated Tube Solar Hot Water panels are glass tubes containing a vacuum seal to deliver the ulitmate level of insultation. Copper pipes are positioned in the center of the glass tube and heat is drawn from the dark glass and absorbed into the copper pipes which share a manifold where a circulating pump moves the heated water into a insulated storage tank. This storage tank allows the water to be used during night and day. Flat plate collectors work using copper lines running in a glass covered collector which sometimes has a external storage tank right on the unit place on the roof. The hot water can then be drawn right from the tank.
While evacuated tube technology is more of an investment, the benefits certainly outweigh the cost! Any additional cost may also be offset by solar hot water rebates!
Evacuated tube collector based systems are the better choice:
Captures more sunlight more efficiently as they have a greater surface area exposed to the sun at any time
Are more efficient in the transferring heat
Can be used in freezing temperatures
If a tube breaks, it can be replaced
Excellent performance in overcast conditions on cloudy days
Require a smaller roof footprint compared to flat plate collectors
Do not have the corrosion problems several flat plate collectors on the market can have
The final decision depends on your investment budget and overall needs. A Clean Energy Centre Consultant has the expertise toassist you with information to make the right decision. To have a obligation free and friendly chat with a Clean Energy consultant; Contact the Clean Energy Centre.
Yes - most homes are suitable, particularly considering evacuated Tube Solar Hot Water systems are the most efficienct at heating water from the sun's clean nergy. If you have a N/NE/NW facing roof space, then most definately. Your internal plumbing will need to be checked for compatibility and this can be done through our free home survey and quote service.
It depends on your current hot water usage, but a rule of thumb is for 3-4 people; a 270 litre tank with 15 evacuated collector tubes, 4-6 people; a 340 litre tank with 32 evacuated collector tubes should be sufficient.
Pricing is affected by your eligibility for government rebates, the current value of Renewable Energy Certificates (RECs) which can change on a monthly basis, the current Solar Hot Water system cost, installation requirements, and your specific system needs.
A short conversation with a friendly Clean Energy Centre consultant will determine your specific rebate eligibility and system requirements, and can provide a quick indication of cost.
Closed loop system: Circulates glycol (antifreeze) fluid through the system without needing a water supply. Suc a system requires a heat exchanger to transfer heat into the water storage. Evacuated Tube Solar Hot Water systems typically use a closed-loop system.
Open-loop system: Circulates the water supply through the Solar Thermal Panel.
Questions on Savings and Pay-Back periods:
A gas solar hot water system in Brisbane could save up to $800 off your annual energy bills compared to an older electric hot water system, and up to 7 tons a year less greenhouse gas emissions. Solar hot water can be up to 87% efficient, that is you only use a bit more than 10% of the energy of an older electric or gas hot water heater.
There are several relatively inexpensive ways to reduce your hot water demands, including low flow shower heads and insulating hot water pipes and tanks. Domestic hot water is the second-highest energy cost in the typical household.
The calculation of long term cost and payback period for a household SWH system depends on a number of factors. Some of these are:
- Price of purchasing the Solar Hot Water system (more complex systems are more expensive)
- Efficiency of the Solar Hot Water system purchased
- Installation requirements and cost (position and roof height can affect the material and labour requirements)
- The state and government subsidy for installing a solar water heater
- Price of electricity per kWh
- The typical kWh of electricity used per month by a household
- Annual tax rebates or subsidy for using renewable energy
The solar hot water system will produce hot water every day. A solar hot water system is a long-term investment that can deliver a payback in as little as three years. As prices go up, the payback period will lengthen.
However, please keep in mind that Solar Hot Water systems are a similar price to many other home renovations and consumer goods, of which they will never pay themselves back e.g. home theatre, new carpet, swimming pool, a new kitchen or even a car. Solar Hot Water systems will save you over $500-$800 a year, whereas a typical hot water system will cost you over $500-$800 per year. So although a Solar Hot Water system might cost up to $2500 or more, after 3-6 years it has paid for itself in savings and delivers FREE hot water every day thereafter. A non solar system costs $1500 installed, but after 8 years can cost you around $7900 when the purchase price and running costs are considered.
Questions on Rebates:
Many solar companies claim to send surveyors to your home, but really they are only a salesperson. We properly survey your home and provide you with a tailored quotation based on your individual homes specifications.
Our trained consultants and technicians are just that, technicians. As a consultant; our mission is to help you make the right decision that takes into consideration not only your needs now, but also your future needs. Our objective is to save you money and see you satisfied beyondexpectations.
The complexity of making sure a home is suitable for a Solar Hot Water system requires experience to make the right recommendations. The Clean Energy Centre are experts in Clean Energy Solar Hot Water, we have many years of experience, and are happy to sit down with you and explain to you the technologies and options likely to best suit you.
If you are building a new home you are not eligible for a rebate, but for most other situations you will be eligible for a rebate when you are replacing or upgrading your hot water system to solar. A Clean Energy Centre consultant can confirm your rebate eligibility prior to placing your order.
Questions on Solar Hot Water system reliability:
Solar hot water systems do need bright sunlight to produce heat. There is usually enough energy to provide some hot water even on a rainy or overcast day. However, this is why a gas or electric back-up booster is important, just in case it is not quite enough for all of your hot water.
Yes, your solar hot water system will provide most or all of your hot water even if you lose power or gas, meaning you can have a hot shower anytime you want.
Actually, a lot of Clean Energy Centre customers have found they can turn off the electric or gas heating back-up booster, as the Solar Hot Water provides more than their water heating requirements.
This depends on the type of solar flat panel and the density of cloud. Flat panels do not contribute as much as Evacuated Tube Solar Hot Water systems in cloudy conditions. In moderate cloud density solar energy can still be collected and used. In heavy density cloud, probably not. If you take your solar calculator out on a cloudy day, you will find it will still work.
Solar hot water systems are covered by Australian standards and installed by trained professionals. The actual life of the solar hot water system is expected to be more than 25 years. Solar hot water has been used in Australia for over 40 years with many systems lasting over 30 years.
Yes. Solar hot water systems are designed so that they need little or no maintenance. Dust typically reduces output by less than 5% but since solar panels are sloped and curved, the rain keeps them clean. You may need to hose them down after long periods of little rain but it will make very little difference if you don’t.
Yes. Solar hot water panels and evacuated tubes are made of toughened glass and are generally indestructible. They are also sloped and curved so hail tends to glance off rather than hit directly. A single tube can be replaced in the event of damage without affecting the rest of the system, unlike flat plate solar hot water where the whole collector would have to be replaced.
As accredited installers, our installations comply with the Australian Standards for solar hot water systems and are done by qualified and trained plumbers and electricians.
Questions on how Solar Hot Water systems work:
No. The systems are designed to never reach above 85°.
There are two kinds of solar panels available today. A solar electric or photovoltaic panel captures the sun's light energy and converts it into electricity. A solar hot water or solar thermal panel captures the sun's heat energy and uses it to heat water for faucets and showers. This hot water can also be used to provide heat for your home with radiant tubing in your floors.
Here are the basic components of a closed loop system:
- Solar Panel(s) to capture solar energy.
- Circulation system to move a fluid between the panels to a storage tank
- Storage tank for the hot water
- Heat exchanger to transfer the heat from the sun-heated fluid to your water
- Backup heating system to give you hot water on cloudy days
- Control package to regulate the overall system operation
Solar Panels are flat boxes with tubing running through them and a glass cover. They are generally mounted on the roof, but can be on the ground or pole mounted. Fluid - either water or food grade glycol - flows through the tubes, collecting the sun's heat energy and carrying it via a plumbing line to a hot water tank in your utility room or basement. The number and total area of the collectors will be determined by your hot water needs. The collectors are supplied by the manufacturer or vendor of the solar hot water system.
In general, there are 2 types of solar panels for Solar Hot Water systems:
1. Glazed Flat Panels - simpler, less expensive, quite efficient.
2. Evacuated Tube - somewhat more efficient at capturing solar heat energy at low angles, but far more expensive.Usually a flat panels salesperson will state their system performs best and a sales person of Solar Evacuated Tubes will state the same. Independent testing has concluded that evacuated tubes perform best in the Australian climate and flat panels closely second. Evacuated Tubes are very effective in colder climates, and will even heat water in sub-zero temperatures. There are several examples of Evacuated Tube Solar Hot Water installations in the snow fields operating effectively.
The storage tank stores water that is heated first by the sun. If the temperature of this water is too low due to cloudy weather, then the backup heat source kicks in to bring the water up to temperature. There are many kinds and sizes of tanks at various prices. Their purpose is to store water that has been preheated by the captured solar heat so that you don't need to rely as much on heating it with some other energy source (e.g., electric, oil, gas, etc.).
The transfer of the heat from the fluid circulating in the pipe to the surrounding potable water is accomplished by a heat exchanger. Heat exchanges are used in several types of systems & are not always required. There are two basic types:
Internal Heat Exchanger - located inside the storage tank and included with the tank component of the system. So with this type you would not need to purchase an additional heat exchanger.
External Heat Exchanger - may be located free of the tank or attached to the outside of any tank. In systems that use an external heat exchanger, the tank and the heat exchanger are considered separate components.
All Clean Energy Centre Solar Hot Water Systems come with the required heat exchanger.
Yes, you need a backup source of heat for cloudy periods or in the winter when hot water use usually increases and the amount of heat taken from the sun generally decreases a bit. Most water storage tanks supplied with the Solar Hot Water system are supplied with an electric or gas back-up heating source which heats water when you need it. However, not all systems are supplied with this, and are unexpectedly an optional extra. Make sure you clarify this first prior to purchasing.
All Solar Hot Water Systems supplied by the Clean Energy Centre are supplied with a back-up water heating source.
The Clean Energy Centre provides complete solar hot water kits because they are a proven, simple and very cost effective technology for generating hot water. Although, for large commercial projects, we will design/build a system per your specifications. A well-designed system will provide 50-80% of a home's hot water needs (less in winter, more in summer), and can pay for itself in less than three years depending on how your water is currently being heated. After the payback period – all the hot water your system generates is FREE.
Questions on installing a Solar Hot Water system:
Very simply, old copper hot water tanks run very inefficiently, even when they were new. But after many years of use, lime scale will reduce their performance even further. When installing a Solar Hot Water system, it is important to install a modern more efficient tank to get the most out of your solar gain.
"Adding solar tubes to an old tank would be like converting your car to LPG and running it on semi flat tyres"
It depends on the council’s regulations, so it is best to check with your local council. We can do this for you.
No, but updating your Home and Contents insurance is a good idea if you have a solar system. As with all major household purchases, make sure that your solar hot water system is included.
North-facing roofs are ideal for solar power and solar hot water systems. However, most systems can work up to an angle of 45 degrees off North, or a system can be designed on a side-pitch array frame for West, and West Facing roofs. If installed onto flat roofs they can be tilted to face the sun.
A typical installation typically takes less than one day depending on your property. We will inspect your site to determine the ease of installation. The installation includes connection of the solar hot water system to your existing hot water pipes, to mains power, and to gas if using a gas booster.
Generall - only 4 - 5 hours. There can be exceptions to this - depending on the installation challanges encountered
Your roof has been designed to carry a lot of weight and most roofs will hold solar hot water systems without the need for reinforcement. The Clean Energy Centre consultant and installer will design your solar hot water system to take account of the roof structure. Solar hot water systems are waterproofed so the roof won’t leak.