<b><b>Andrew Leech finds that the drive towards minimal carbon dioxide emissions is having a profound effect on greater energy efficiency in heating systems, not only in new build homes but also in refurbishment</b></b><br><b>Things are starting to change in the heating sector. The drive to reduce greenhouse gases is pushing innovation and imagination to its limits to find new ways of keeping us warm.</b><br><b>Vaillant&amp;’s sales and marketing director, Stephen Zouch, explains: &amp;“In our industry there have been few dramatic or revolutionary developments in recent years. But that is about to change, not just in the way boilers are manufactured, but also in the way they are powered. We have been working on some pretty groundbreaking technology to find alternatives to burning fossil fuels and the ultimate energy efficient product.&amp;” </b><br><b>The company&amp;’s Fuel Cell Heating Appliance (FCHA) has just been given the go-ahead for full-scale field trials across Europe. In its most simple form, it operates like a car battery, taking hydrogen and oxygen, which react electro-chemically, to produce heat and power with the only emission being water. </b><br><b>But the fuel cell is not the only radical technological advance Vaillant is planning. It has developed Zeolite - Greek for &amp;“boiling stone&amp;” - …