Solar Water Heaters
Smart and sustainable. Solar water heaters keep your home supplied with free hot water from the sun.
What's in a solar heater?
A solar heater is made up of a tank and collectors. Collectors can be solar panels or solar tubes. These tubes catch sunlight and heat water.
In Singapore, it is cloudy, so it is better to use solar tubes instead of flat panels. The vacuum in tubes allow better heat retention.
How do solar heaters work?
Solar heaters collectors absorb free sunlight. Heat from the sun warms up water that runs through the collectors.
This heated water is stored in an insulated tank. In case of rainy or cloudy conditions, the solar heater will use a back up electric element to heat water.
Don't mix this up! Solar heaters are not PV panels.
They both collect sun energy, but the difference is:
• PV panels produce electricity.
• Solar heaters produce hot water.
There are many panels popping up in Singapore right now. You see them on HDB or building roof tops. As long as you don't see a tank, they are PV panels.
In Singapore, how many rainy days do we have? 20%, 30%, 40%, 50%?
If you guessed 50%, you are right. Our rainy climate affects solar efficiency. This is why solar heater efficiency in Singapore is not 100%, it is 50%.
Solar is still a renewable energy heater, but you should understand how our climate affects solar heaters before you commit. Solar will not run at full efficiency in Singapore.
But solar heaters are doing well in Australia!
100% agree! If u are installing a solar heater in Australia, it works very well.
In Australia, there are fewer clouds, and you get direct ultraviolet rays. That is a perfect climate for solar. That is also why in Australia, you get sunburns easily. In Singapore, you won't.
Part of making an informed decision is to understand this climate. The cost of solar is about $8,000. It is no small amount. If you are going to drop money like that, it is wise to do some research.
Many homeowners don’t know much about their solar heater.
We have met people who only know there is a tank there when it starts to leak. They are aware of the panel, but not the tank.
We have also met people who don’t know the solar heater has a heating element. They think the solar panel generates all the heat the heater needs.
It is shocking, but it is not their fault.
As the owner of a huge house, you are very busy.
You don't have time to figure out how the solar heater works! This is not your main job.
One day, your family tells you they have less hot water, so you call the service man. You are not at home to attend to the service guy. So, your helper takes the service man to the heater.
The service man checks the heater and says, if the family says there is no hot water, you can turn on this switch. Easy! So the helper turns on the switch whenever there is no hot water. Then bo daiji (no problem) already right?
You use the heater this way for a few years, until...
your tank leaks. Only then, do you realise you have been using high power electricity to heat 300 litres of water. (A normal 5-person family can get by with 100 liters.)
But no one tells you, so you don’t know. Out of convenience, you call the same solar people. They sell you a replacement solar heater. Now, the same problem will repeat.
But this happens if you are busy and have no time to care. You just pay the bills. You don't know where all the electricity is going to. How can you tell?
The truth is in Singapore, Solar uses a lot of electricity.
It is never too late to learn to save money.
Most people assume their solar heater never uses any electricity. That is not true. Assumptions are very dangerous. It will cause you thousands of losses spread out quietly over many years.
It is time you found out the truth. So you can make a decision if you want to go back to solar.
If your family is small, don't use solar. This is why.
We have worked with families in huge houses, with only 3 people in a landed home. They install a 300 lit solar tank. They feel it is good, because they don't run out of hot water.
But with a 300 lit solar tank, you are paying $8,000 for 3 people. That's crazy! Don't make this mistake!
Solar is not enough for large families.
Even 300 lit won’t be enough. This is when people start turning on the electric element. Before you know it, your heating bills will multiply.
A 300 lit electric heater drinks a crazy amount of energy. It is a clear over-spec situation. Most people like to over-spec the heater just to be safe, but we don’t do that here.
Custom solutions create the perfect fit
Your space constraints, shower habits and budget are important factors to consider. You need a heater expert for that.
Don't blindly go for a popular or trendy heater. That causes expensive mistakes, like installing a 300 lit solar for 3 people. It feels terrible when we see people being cheated this way.
We agree with NEA. In SG, Heat Pumps are better than Solar.
2025 Update: This is why our $300 NEA Climate Vouchers don't let you claim for solar heaters. Instead, they only allow you to claim for heat pumps.
NEA knows the efficiency of solar heaters are low in Singapore. This is why they don't promote solar heaters. There are too many clouds in Singapore for solar to be efficient.
How did heat pumps win in the end? 🐢
Solar vs. HP is like the story of the Tortoise vs. Rabbit. A tortoise and rabbit entered a race. Even though the rabbit was quick, he naps often. In the end, the tortoise won. His slow and steady pace, wins the race.
Though solar heaters have a higher efficiency of 100% vs. heat pumps 80%, solar (like the rabbit) is not consistent. In Singapore, solar heaters can’t work half the time. That is why the heat pump overall efficiency is higher.
Though AOS has solar, we recommend heat pumps.
Solar is still great for overseas markets. The downside is, they don't work in countries with heavy cloud cover. They don't work on hazy or rainy days.
Compare that with heat pumps, which work 24 hours, 7 days a week. Overall efficiency of heat pumps is 80% vs. solar's 50%. To find out more about heat pumps, click below.
