Design features of the Xstream range of hot water cylinders - Vacustream development:

Material used in construction:

The hot water cylinder has a solid high strength corrosion resistant Derakane®  Epoxy Vinyl Ester inner tank. This product (Derakane®) is used globally in the storage of high temperature (100 °C plus) liquids, concentrated acids and aggressive alkaline products such as caustic soda. The product is also proven under high pressures. Derakane® is Food and Drug approved for use in potable water.

The Xstream range of hot water cylinders, in using the material characteristics of this material in the application of hot water storage has achieved the following distinct advantages: 

  • There is no need for an anode with the resultant maintenance costs in replacing it.
  • Glass and epoxy vinyl ester resin are poor conductors of heat, therefore heat loss is minimal.
  • Low heat losses ensure maximum utilization of energy absorbed.
  • High density polyurethane, injected between the inner tank and the outer glass reinforced UV stabilsed gelcoat casing, forms a chemical bond that results in a solid, rigid insulation barrier all around the inner tank.
  • The product is light and easy to install.


SABS Accreditation:

Hotmix (Pty) Ltd trading as Xstream Hot Water cylinders have ISO 9001:2001 accreditation - permit number LS 2042.

The 100 litre tank has been submitted to the SABS to be added to the rest of the Xstream range of hot water cylinders carrying the SABS mark. Manufacturing processes and materials used are similar to the rest of the SABS approved range of Xstream tanks.


Genergy Evacuated Tubes:

Genergy's evacuated tube technology uses patented "3-Hi" vacuum tubes.  The absorbing coating found on the inner layer determines how efficient the vacuum tube will operate.  The method and material of this coating will also define the life expectancy of the vacuum tube. 

Most vacuum tubes use a hi-tech reactive sputtering process to coat the inner tube.  Most commonly this coating is made from an aluminium and aluminium-nitrogen coating (Al-N/Al), which is the primary absorbing coating. 

The patented interference film coating "3 Hi" vacuum tubes use 3 systems to ensure the most effective heat absorption. This included a AL-N/AI layer but also a separate aluminium and copper layer.  

The added layer conducts heat better and also stabilizes the coating allowing for a much longer lifespan of 20 years or greater. 


Solar Water Heaters:

  1. Affordability and quality are the key consideration when selecting products. This is particularly true of low-income housing where future maintenance, repairs and replacement will present a challenge to the home owner and insurance cover is unlikely.
  2. The cheapest solar water heaters are generally Open Vented units which are imported, or assembled in SA from imported products. However, these systems come with draw-backs, including, questions about longevity, corrosion, overheated water supply, maintenance and of course the irony of the carbon emissions associated with importation. 
  3. There is also a growing local production and experimentation with different materials and products, some of which present solutions to the above concerns.
  • The recommended Open Vented SWH System:
  1. Through the Kuyasa experience and working closely with Xstream Geysers, we have assisted in the development of a robust open vented system that we are confident will provide the service levels and life-span required for our market.  While other systems may still come onto the market and the SWH manufacturing market in South African is dynamic, we are confidently able to recommend a product that has superior performance qualities, delivers balanced cold/hot pressure, 'safe' tempered water at between 50 and 60°C, approved water quality and (importantly) will last a very long time, with a life-time guarantee against corrosion.



Genergy Low Pressure 110 Liter Solar Water Heater

Genergy was contracted to supply 1500 units at the start of the Kuyasa CDM Project, this was due to the fact that there were no locally manufactured Solar Water Heaters at the time. 

Visit Genergy's Website for system specifications.

IsoBoard Ceiling Insulation

Visit the IsoBoard Website for physical properties.