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Zenex Technologies Ltd

The company has worked for the past six years on the development of energy saving devices in the area of heating water for domestic and commercial applications. Current developed designs and products are on sale in the UK but only in small numbers to date, relative to the market potential.

A Zenex objective is to develop a viable and profitable business in the area of energy efficiency based on its inventions. At present it owns four patents and has six further patent applications pending.

One major area of development has been the Zenex GasSaver, awarded a UK patent in 2007, which comprises a condenser and heat exchangers which recover heat efficiently from boiler flue gases in heating and hot water systems. This device has been recognised, approved and defined by the Building Research Establishment as a generic device, being a ÔPassive Flue Gas Heat Recovery DeviceÕ, (PFGHRD), thus verifying its ability to recover and use heat energy which is otherwise lost to atmosphere. The Energy Savings Trust (EST) has approved the device as Energy Saving Recommended (ESR). It is supplied by boiler manufacturers Baxi and Alpha.

The energy savings are substantial. Independent studies show that gas bills and carbon emissions are reduced by 15% to 25% and the consumption of domestic hot water (DHW) is reduced by 5%. Zenex systems provide hotter water faster thus giving improved performance in addition to its savings.

1,600,000 new domestic ÔcondensingÕ boilers are installed in the UK each year. These are stated by Government and the manufacturers to have a SEDBUK ÔefficiencyÕ of 90% or over. SEDBUK is not the true efficiency in normal domestic use. In fact, modern boilers do not condense effectively.

The Government has a mandatory requirement that all domestic boilers should be ÔcondensingÕ, but there is no mandatory requirement for ÔcondensingÕ boilers to condense at all! This fact is illustrated by the plumes of hot moist gases which can be seen escaping from the flues of new domestic boilers.

It is a scientific fact that, if a boiler does not condense significantly and if the flue gas exit temperature is as high as 85degC, which is normal, then it cannot possibly be more than 85% efficient. In practice, the average efficiency of even the best new boiler is usually significantly lower than this. Tests by DEFRA have shown at least one figure as low as 30%.

The GasSaver effectively recovers the latent heat of condensation and also lowers the flue gas exit temperature to within 10 degrees above ambient by efficiently recovering the heat energy.

Further Zenex developments include the introduction of a cooling, mixing stage after the preheating of the incoming cold mains water prior to its input to the boiler and also an addition of a small cylinder of some 25 litres on the primary circuit to provide an additional pre-heat store. This results in a system with high performance, high efficiency and a reduction in domestic hot water use.

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