Copper boilers - the over-looked energy enemy

Monday, 21 September 2009

Rotex, a German based manufacturer of heating systems, believes that it has the answer

As rocketing fuel prices begin to hit the nation’s pockets and homeowners look to reduce energy consumption still further, it could be that we are all missing a trick, as we overlook a vital part of nearly every domestic heating system – the humble copper cylinder.

It’s becoming increasingly obvious that it is a major contributor to energy loss, responsible for millions of pounds of wastage every year. Open the door to any airing cupboard and you can literally feel the energy wasting away and most of us simply accept it as the price we pay for keeping our clothes warm.

That warmth represents little more than lost heat. Being made from copper and constructed from such a conductive material, once water is heated it instantly begins to release that energy so, by the time you want hot water again, it’ll be lukewarm meaning it must once again be heated – and so the cycle goes on.

Methods like insulating the roof might partially prevent energy from escaping, but it would be more effective to stop it from getting that far in the first place. Even modern polyurethane foam – a highly effective insulant – that’s now placed around most cylinders fails to save the majority of the wasted energy.

Doing away with the common copper cylinder and its airing cupboard and replacing it with a more efficient system is the only answer if real energy and cost savings are to be made.

Traditional heat stores will suffer a heat loss in excess of 10 Kilowatt-Hours (kWh) in the first 24 hour period when water is stored at the standard 65C°. This loss means that, even when hot water or heating has not been used, the boiler is in a continuous cycle of reheating to combat the energy waste.

This results in needless energy usage, a meaningless loss in money terms and a senseless increase in carbon emissions.

Many in the heating industry would suggest that they have already replaced the copper cylinder but that does not necessarily mean energy savings. Products such as combi-boilers will heat water on demand and heat the home separately, seemingly avoiding the issue of waste. However, many of the systems are unsuitable if you require large amounts of hot water and so fail in providing a complete solution.

Rotex, a German based manufacturer of heating systems, believes that it has the answer. It has got rid of the copper cylinder and replaced it with a “plastic cube.” It is delivering a staggering 300% in energy savings, compared to many rival systems and could change the way we heat hot water in the UK – for ever.

Sanicube, as it is known, is a unique double skinned polypropylene thermal store offering an energy loss of only 1.3kWh over the first 24 hour period. This equates to temperature loss of just 3.5 degrees every day.

It works by throwing the copper cylinder principal into reverse. The cube is filled with water when installed and remains permanently sealed. It is heated to the required temperature using fossil or solar energy. Water is then run directly from a mains supply and is heated, only when it is needed, via an exchanger as it passes through the cube. There is an added bonus – potentially hazardous legionella bacteria are prevented from entering the hot water supply.

However, there is a long way to go before the industry is persuaded to give up its love of copper. Most still prefer the trusted and tried and energy savings seem secondary.

It must be accepted that every home needs a ready and adequate supply of hot water, for bathing, washing and cleaning. The means of providing this supply should ideally be energy efficient, environmentally friendly and maintenance free but there is no doubt that even the most efficient copper cylinder will only deliver a five to 15% saving and then only compared to other cylinders.

Building Regulations require all hot water storage cylinders to be insulated. This insulation is usually provided by a foam coating which maintains a heat loss not exceeding 1 W/L of capacity. Foams have been developed which are totally free of harmful CFCs so the system is greener than it used to be but is still unable to compare with alternative hot water methods.

Integrated thermal storage is the generic term for a British development which supplies both heating and mains pressure hot water in a more cost effective way. By dramatically reducing boiler cycling and giving much faster response times to demands for heat it can as mentioned earlier, reduce the fuel usage by between 5% and 15%.

Companies such as Rotex believe this is too little too late in the move to reduce energy consumption and intend to continue selling their brand of green heating until the industry changes.
If Government intervenes to force through such changes we may be saying goodbye to the copper cylinder for ever.