Today I spoke to Newark Cylinders - a positive conversation, wherein I was told that they could build to order a bespoke thermal store copper cylinder to my specifications, and turn the order around within a week - and within my budget too!

Unfortunately, the conversation with Baxi regarding the Ecogen microCHP boiler didn't go quite so well. I'd spoken to someone from Baxi at Ecobuild earlier this year, explained to him what we wanted to do (ie run an Ecogen via a thermal store, so we could programme the CHP timing independently of the hot water and space heating demand), and he seemed to think this was all fine. Of course, it was just an initial conversation at that point. Now we're at the point of actually ordering one, I made a call to clarify some technical details, and was told by another Baxi representative that this type of installation was "not supported" (sounds like software, doesn't it?) and could quite possibly invalidate the warranty. I then tried to call the guy who I spoke to at the trade show (I still have his business card), but his voicemail indicated he's on holiday until next week.

I then re-investigated the only other microCHP option, Whispergen. E.On have the sole UK distrbution rights to this product (a factor that helped me in selecting the Ecogen previously), but there's little mention of it on their website. Some extensive Googling was required, eventually yielding a contact name and number - but the number didn't work. I tried an alternate number and eventually got through to this guy's voicemail; left a message.

So depending on what these two people say when they return my calls, the heating strategy for the Withington Co-operative Eco-house may be back on the drawing-board next week!

Meanwhile, some good progress with the PIR insulating on-site today.