Envirosun is Enviroheat’s sister brand in solar hot water heating
Envirosun has been manufacturing solar hot water products in Australia for decades now and has evolved into a market leader in quality, performance and affordability. Envirosun have a solar hot water heater to suit a wide range environments and climates.
Polyurethane is formed through the chemical reaction of two liquids with the mixture then injected into the contained space around the hot water storage tank and outer casing.
As the mixture is exposed to air, it expands to up to 10 times its liquid volume. In so doing it fills all of the contained space including the smallest of crevices. As the mixture dries it hardens to form a closed-cell structure that is a rigid and impermeable structure.
Compared to fibreglass insulation that allows air to permeate, polyurethane is airtight. The resulting insulating barrier works at three levels: the gases trapped in the cells resist conductive heat losses; the air-tight structure prevents convective heat loss otherwise caused by the flow of warm air to the cooler surrounds; and condensation heat loss, normally caused as warm air is introduced to cold air, are avoided
The solar hot water cylinders of all Envirosun storage tanks are encased within a polyurethane foam insulation system. The polyurethane mixture is pressure injected into the space between the cylinder and the external sheet metal casing.
The combination of metal and foam contributes to structural rigidity and is the basis of its excellent heat retention properties. Heat retention = more hot water for a longer period of time and that equates to money and energy cost savings
The solar absorption fins in our solar collectors are designed to absorb more of the sun’s energy and radiate less back to the environment as heat.
To achieve this they undergo a two-stage electroplating process. They are first plated with a layer of bright nickel and then re-treated with an over-coat of black chrome. This creates a ‘spectrally-selective surface’ that absorbs more solar radiation and re-emits less thermal energy. The underlying mechanisms are relatively simple. In the short wavelength part of the spectrum, the absorber behaves like a black surface and soaks up most of the sun’s energy. In the long wave length part of the spectrum, the absorber behaves like a silver surface and re-radiates little of its heat.
Envirosun’s black chrome absorbers plates have the highest efficiency solar selective coating available and they deliver performance gains about 20% above those available from such non-selective treatments and other brand solar hot water systems sold in New Zealand
Envirosun solar hot water panels are secured inside high grade coated aluminium frames to reduce any corrosive materials on your roof
Our collectors are fitted with solar glass that is highly translucent and very strong.
It’s intended as maximising the amount of solar energy that is captured by the collector absorber plates (panels) while protecting them from impact damage. To explain, this, it’s first necessary to understand how a solar collector uses the ‘greenhouse-effect’ phenomenon to heat water.
As the sun’s rays fall on the glass cover are a form of short wavelength radiation. Most of the solar radiation passes through the glass but some is reflected or absorbed. The transmitted portion of solar radiation that reaches the black copper absorber plate, heats it and the water that is contained inside the pipework. The hot absorber also re-radiates thermal energy (a form of long wavelength radiation) which, in the absence of a cover, would escape and allow the plate to cool. The glass cover, however, acts as a reflector of the long wavelength radiation and bounces it back to the absorber, thereby containing the heat. Glass that has higher iron levels absorbs more solar radiation and allows less to reach the absorber plates. Low-iron glass can transmit about 91% of the incident solar radiation. Envirosun solar glass is produced with very low levels of iron impurities. Envirosun solar glass is also tempered using a heat-treatment process
Electric incoloy elements
Gas instantaneous systems
Envirosun AS split system solar water heaters are also available. They come in 3 different to suit most home sizes 250 litre, 315 and our largest is 400 litre, these are known as the Envirosun “AS” solar hot water systems
Active systems only require the solar collectors to be installed on the roof with the storage tank situated at ground level or any other convenient and out-of-the-way location. The operating principle of these systems is relatively simple – when the solar collectors are able to add heat into the storage tank, a small pump is switched on to circulate hot-water from the collectors and replace it with cool water from the tank. Once the tank is full of hot-water, the pump is switched off, but ready for the next cycle.
While pumped systems have been around for many years, modern electronics and materials have brought improvements in both function and reliability. Today’s Envirosun AS systems adopt many of these technological advances and blend them with our collector technology, to create our range of high-performance active solar hot water systems.
The Envirosun AS Range of solar hot water systems uses a small circulating pump and electronic microprocessor to transfer the heat absorbed by the solar collector to the separate storage tank.
The circulating pump draws very little electrical power (less than 28 watts) and only operates when the microprocessor determines that there is a useful gain to be made.
The microprocessor takes information from temperature sensors on the solar collectors and in the storage tank. When the collectors are 6°C hotter than the water in the storage tank, the circulating pump is operated. When the differential falls to 4°C or lower, the pump is not operated. The microprocessor also uses the sensor information to control a suite of over-temperature protection modes:
- if the water in the storage tank reaches 70°C, the pump is stopped
- if the collector temperature reaches 190°C, the pump is cycled on to control the temperature to below 185°C
- if the collector temperature reaches 200°C the pump is not operated
- if the tank temperature has risen above 70°C and the collectors are cooler the pump is run