Baxi Ecogen micro-CHP

[openspaceman]

Does anyone have any knowledge of these boilers incorporating a stirling engined generator?

I think the lineage of the stirling genset here is from Phillips research post WW2 and then further developed by Sunpower before British Gas took an interest but then dropped it in around 2112.

My interest would be to use it November through to March top top up my growatt battery as well as provide heat, though I generally heat by logs.

[openspaceman]

An update; Baxi discontinued the ecogen, they say there was poor uptake. Microgen have a very similar unit on sale as a 6kW heat only unit made in China but not CE marked as yet.

[dan_b]

Years ago I almost jumped in and bought the "Flow" mCHP gas boiler - which would at that time have been tied into a feed in tariff payment as well. I even went on Flow's elec & gas tariff and was all set to buy it, but at the last minute got cold feet. Not long after, Flow scrapped the boiler project and then subsequently also went bust as a utility supplier. Bit of a shame but there you go.

[openspaceman]

Makes you wonder whether it was a lucky escape or not.

From what I read there were a number of failures of the actual stirling engine. Baxi don't say if it was that or the poor take up that decided them to cease production. Also we don't know how much they had to licence the technology for and what effect that had on the price.

On the surface it looked a good match for the deepest part of the winter as it would augment electricity from the panels and provide heat while it was running. From my perspective 6kW of heat is easily enough to keep this house warm and the extra utility of the electricity production makes good use of the gas energy.

There must be thousands of the ecogens still running out there but little feedback as to how well they perform.

[Stinsy]

Not sure they fitted many. Would be a lovely augment to a solar/battery system…

[openspaceman]

Would be a lovely augment to a solar/battery system…

Yes it appears to be a very good fit with my Solar PV and battery.

Not so much use for those of you with EVs.

The alternative would be Seebeck devices but from what I see they will not produce enough electricity unless you need a lot of heat.
I can envisage a little 4kW woodburner with watercooled TEGs and underfloor heating but that wood get 160W at best and how much would go in parasitic loads of a water pump?

[billi]

... a far as i know Valliant at one stage argued against the Stirling engine and had a cooperation with Honda gas engines for the ecoPOWER 1.0 micro-combined heat and power system , at the time i was very keen on CHP ideas , but none of those on the market , would have justified the costs for my idea of supplement the missing PV power in winter

[openspaceman]

In about 1980 Calor promoted the "totem" which was an asynchronous propane fueled generator powered off a fiat 1100 engine running at a constant 1500 rpm. It was sufficient to power and heat 4 modern well insulated new builds. The engines didn't last long. The firm I worked for came across one that ran a Scottish hotel briefly.

Now we have decent battery storage there is no need to the constant speed constant running but it would deliver too much power for a single dwelling (mind it might be about a match for a two EV household).

Given that lpg is cleaner than petrol, oil changes fewer and total run time would need to be no longer than a conventional ic engined car for the same mileage and a modern permanent magnet alternator and computer management would keep the engine on its sweet spot I think it may have legs.