'Breath of Fresh air' on unthreaded today makes a suggestion that since Our Dear Deputy Leader seems intent on preventing us building sufficient generating capacity to power the country into the next decade we should be looking at installing our own back up systems. Over the years I've been keen to explore the various options, ruling the usual suspects out through expense or impracticality. I've been struck recently however by the advances in microCHP, with a Baxi system currently available (though apparently at high cost) and Worcester aiming at introducing a second generation system next year. These systems replace conventional gas boilers with a condensing boiler, but with an added stirling engine to produce electricity from the waste heat. Whilst not covering the whole needs of a modern house, the system seems to have the advantage of being readily fitted to many properties, and in the event of general power cuts provides enough power to light a house and cover essential needs.

There seems to be a lot of discussion about whether it's really 'renewable' or not, but notwithstanding that, it strikes me as being both useful and practical. Does anyone have any experience or deeper knowledge of these systems and their practicality?

Is there a feed-in tariff for such things? I'm not sure I necessarily approve, but there's no point in looking a gift horse in the mouth if it's available for more than wind or solar. Or does the fact that it works when you need it rule it out..?

Not so sure about a feed in tariff but I am fairly certain there is a boiler replacement grant available. Suppliers will have all the details.

I have also taken an interest in CHP but realise it is still in its infancy in the UK. I like the idea of one source of energy, gas, being able to provide both heat and electricity. If combined to an LPG storage tank theoretically it is possible to go completely off grid.

The current units generally state 80-90% efficiancy but that is combined. The electricity generation is usually around 27%. This not an over ruling factor for me but in the summer to generate electricty you still generate heat just when you don't need it. If I could find a unit that generates heat during the winter and utilises heat during the summer to generate electricity then the old wallet might make an appearance.

Yes, there is feed in tariff available for mCHP. I think for the first 30,000 installations, with a review after 12,000 have gone in. (Expectations seem to be that this will take until well into 2012.