Pre-insulated flexible piping makes a significant contribution to sound long-term energy management says Peter McEntee

Increased pressure on public and private finances in a climate of high fuel prices makes a strong case for better energy management. Economic necessity will force users to find more efficient ways to convert fossil fuels and other forms of energy into heat for warming homes, workplaces and other buildings.

The same pressures will help to cut carbon dioxide (CO₂) emissions, with considerable benefit for the environment.

If we are really serious about energy management in heating, we must look at complete systems. A modern energy efficient boiler, for example, is only as good as the radiators or underfloor heating arrays it serves - and the pipes that complete the heating circuit. In different words, a clean-burning gas or biomass boiler, ground or air-source heat pump, or solar collector will reduce a building owner's energy costs and CO₂ emissions, but the full efficiencies will not be realised if heat energy is lost between boiler and radiator, or if the radiator does not quickly produce the desired comfort levels.

Ensuring minimal heat loss

In certain commercial and institutional situations heating (and cooling water) water pipes may need to pass from one building to another. And, in many eco heating systems, hot water will need to travel from an outdoor heat pump into the heated building.

We may also see similar installations in new residential developments, where a large biomass boiler could provide more economical and environment friendly hot water than scores of individual gas boilers. In designing multi-building or community heating systems, special attention has to be paid to ensuring minimal heat loss between boiler and radiator, given that long distances and exclusively underground pipe runs are involved.

Traditionally, piping from boiler plants to satellite buildings was cast iron - later superseded by ductile iron - with heavy insulation and cladding. Metal pipes had a limited lifespan because they were susceptible to surface corrosion from the manufacturing process, and felt and foam insulation rapidly lost performance if it became saturated with water underground.

Development of pre-insulated 'plastic' piping has provided a real alternative to traditional underground hot water lines, offering zero corrosion plus reliable insulation over an expected lifespan of more than 100 years. Because it is flexible it is also simple to install and bends readily to accommodate obstructions or sharp changes in direction.

The range of Microflex pre-insulated pipes, for example, consists of one, two or four PE-Xa pipes surrounded by thermal insulation of micro-cellular cross-linked polyethylene foam in a closed cellular structure, with low water vapour diffusion and excellent resistance to extreme temperatures.

Pipes and insulation are contained in a corrugated HD-PE casing. A range of pipe and casing sizes suits varied requirements for circulation of heating water and hot or cold potable water. Flexible and lightweight, the pipes are easily laid in trenches. They are supplied in custom lengths up to 100m, and are easy to join or connect to indoor plumbing systems.

Pre-insulated piping is designed to save time and cost during installation and is completely maintenance free. By far the biggest advantage, however, is that heat wastage is negligible - even on extended pipe runs - so this contributes to sound, long-term energy management and reduced CO₂ emissions.

It is also future-proof, in that it complements today's technology in heating systems - and it will still be serviceable when boilers or other components are replaced with the advanced technology of future generations.

• The author is sales and marketing director of Watts Industries