Both condensing and the new CHP boilers are both highly efficient (over 90%). Condensing boilers recover extra heat from the exhausted steam that is normally lost with conventional boilers. CHP boilers work by turning the wasted heat from the exhaust steam into electricity using a Stirling Engine. They both are therefore less polluting than conventional boilers.

But does either system have an inherent advantage over the other?

One clear advantage for the CHP is that you would be able to make money by selling ‘ROCs’ that you could earn from the electricity produced with the CHP. It would also provide electricity to the home that may be cheaper than you can buy from the national grid ,depending on the relative gas price.

The downside is that the technology is largely untested, is also probably more expensive and has more parts to break than a condensing boiler. On the whole at the moment I personaly would go with a condensing boiler.

But fundamentally neither system is sustainable. They are efficient, but are still fossil fuel technologies.

The efficient technology being deployed in the boilers is great though. I would hope to see wood pellet boilers fitted Condensing or CHP technologies in the future.

Does anyone know if anybody is working on this at the moment?

Stuart