Factors to consider before buying solar water heaters

A solar water heating system. They help reduce electricity bill. PHOTO | FILE | NATION MEDIA GROUP

What you need to know:

  • A tank should have a magnesium rod to absorb impurities in the water to minimise corrosion. The rod is cleaned after a year to ensure the safety of the tank.
  • To protect consumers from substandard products, industry players want the government to come up with regulations to govern importation of solar panels and electronic gadgets.

About two years ago when the government began enforcing a new regulation compelling property owners to instal solar water heating systems on their buildings, two things happened.

On one hand, businessmen rushed to import solar water heating systems to meet the anticipated big boom, and on the other dozens of property owners were burning their fingers after sinking millions of shillings to acquire sham water heating systems.

The directive, whose compliance deadline elapsed in November 2017, aimed at lowering demand for electricity and lifting pressure off the existing power generation plants by tapping into off-grid renewable energy solutions.

Thus the requirement for new buildings, or extensions, to be fitted with water heaters.

DEMAND

The solar water heating regulations of 2012 required owners of residential buildings with at least three bedrooms or whose hot water consumption exceeded 100 litres a day to instal a solar water heating system.

The regulation also targeted hotels, restaurants, hostels, lodges, boarding schools and colleges with over 200 students, and laundries that handle more than 20 kilos of clothes a day.

Mr Eric Ouma, a Nairobi resident, is one of the homeowners who have complied, hoping to cut down the electricity bill. He spent more than Sh2 million to put up the house.

According to International Energy Agency’s flagship publication, World Energy Outlook 2016, solar water heater technology, owing to enhanced efficiency and cost reduction, has been expanding at a rate of 17 per cent per year since 2000, and has been further forecast to account for the highest product demand in the coming decades.

QUALITY

Mr Ouma, however, says he has also tasted the bitter end of the stick. He approached a dealer in town who installed the kit at a reasonable cost. But it did not take long before the tank began leaking.

Normally, for residential buildings, a solar water heating system - which comprises a water tank and several tubes or flat plate collectors - is fitted on the rooftop.

If the equipment is of poor quality, the tank begins leaking and the water seeps past the roof to the ceiling, damaging it and your house.

To avoid similar situations, experts say consumers must be exposed to precautionary measures, for example product awareness, to safeguard their interests.

Providers advise that there are many factors, aside from cost, that homeowners need to consider when acquiring a water heating system.

TANK FEATURES

Manoj Bakshi - the chief executive officer and founder of Mayu Solar - says that technology used in welding the solar water tank is one of the most critical factor in determining the quality of the system.

He says the water tank, quality of the tank and welding technology used in designing the tank must also be considered.

It is advisable to go for tanks which have been welded through tungsten arch technology. This, he says, ensures that there are no leakages on either of the tank's ends.

“The tank should have a minimum of 1.5mm thickness for durability. Due to poor water quality in some areas, the rate of corrosion can be very high, which effectively affects the life of the tank; hence the importance of using a good quality tank,” Mr Bakshi, who has over a decade of experience in the industry, explains.

WATER CAPACITY

There are basically two types of solar heaters: pressure and non-pressure models. A pressure solar heater ensures good and constant water pressure, but the non-pressure one means the water is under low pressure.

“We always recommend pressurised systems because it has good pressure, takes hot water to different areas of the house at all times and minimises the risk of air locks in the plumbing system,” the Mayu Solar CEO says.

Since a typical Kenyan household may have many visitors over time thus increasing hot water consumption, it is always advisable for a homeowner to go for a system that has a capacity of 300 litres as opposed to a 200-litre system since the cost difference is minimal.

If one goes for a smaller tank that does not meet the household consumption, he/she will be compelled to use electricity to boil water, which eventually raises power bills.

Ideally, a tank should have a magnesium rod to absorb impurities in the water to minimise corrosion. The rod is cleaned after a year to ensure the safety of the tank.

RECOMMENDATIONS

The tank should also come with other features such as a pressure release valve so that whenever it gets to hot and the water is not being used the valve automatically opens to reduce pressure.

“If you manage solar water properly, you will save over 70 per cent on electrical energy. Mayu Solar highly recommends the heat pipe system technology. Because in this system the sunlight falls perpendicularly on the collectors, thus increasing efficiency. An added advantage is that water is not present in the tubes,” the expert explains.

For schools, hotels and all commercial developments, a centralised solar water heating system is recommended.

Once the system is installed, a digital intelligent controller is also a highly recommended additional accessory.

Its function is to display temperature inside the tank and for automatic programming settings.

“It is always important to work with licensed and qualified technicians when installing a solar water system, as it defeats the purpose to have high-quality products installed poorly,” says Mr Bakshi, adding that one of the most important things regarding certifications is adherence to solar key mark EN 12976.

RULES

To protect consumers from substandard products, industry players want the government to tighten regulations.

Dr Alice Kaudia, the former environment secretary, notes that the move will protect consumers from being reaped off and save the environment from unnecessary e-waste.

She also called for the establishment of extended producer responsibility polices to compel electronic manufacturers to take responsibility for management of the disposal of products.