We made it simpler, more robust, with greater reliability and longer life, and overcoming the problems of overheating.
There are many types of solar water heating system, all with the same aim of heating water using solar energy.
In the case of Ubersolar, the choice of design was to use the approach of split/ indirect/ forced circulation with a solar collector using evacuated tubes, and uniquely a vented solar manifold, in preference to other design types.
30 EVT Solar Collector
42 EVT Solar Collector (30+12)
60 EVT solar collector (30+30)
The reasons for this were:
We can use the home’s existing tanks (any make), enabling retrofits, rather than having to replace or use a new tank
We can avoid having tanks on roofs, which are frequently considered obtrusive, and may require structural reinforcement of the roof, but flat roof options are available
Split systems where the tank is separate to the solar collector enables far more flexibility; in locating the tank in a roof void, on a wall, in a cupboard or on the ground up to 20 metres away from the solar collector
Temperature control of hot water in the tanks is difficult, when the solar collector is integrated into the tank, or uses the solar thermal transfer process of thermos-syphon, (the principle of heat rises)
Increasing efficiency by using a solar pump and PV panel (forced circulation), which enables the pump to be turned ‘off’ when the tank temperature has been reached, and also increases the efficiency over thermo-syphon systems
By using vented solar manifolds, the temperature is limited in the manifolds to 99°C, in contrast to manifolds using evacuated tubes with heat pipe risers that can reach 260°C, or flat plate types that can reach 165°C. Such high temperatures in those solar collectors can result in component failure, lower reliability, increased maintenance requirements and reduced longevity
Overcoming the problems of stagnation, where no hot water is being extracted from the system, resulting in overheating of either the tank or the solar collector.
Incorporating ‘Plug and Play’ where the solar manifolds are joined together to make a solar collector of any size, to achieve the required electrical savings, and the required hot water output, all without overheating
Simplicity without compromise, achieving the aim of heating water using stock components, overcoming all of the shortcomings and problems of other design types and heat transfer
Cost, where the design and components result in more savings for less investment, providing a faster payback, higher return on investment, and longer life with far greater reliability.
Other solar water heating design types
Integrated HP tank with EVT (heat piper riser type)
High Pressure Close coupled / direct /thermo-syphon evacuated tubes & tank
High Pressure Close coupled / indirect/ flat plate/ thermos-syphon Thermo-siphon & tank
After years of research, multiple design types, extensive testing at the SABS, we achieved our goal with systems passed in 2014 and SABS Mark given in November 2014.