Earth Notes: On the Ecobuild Exhibition (2012)

Lots and lots and lots of PV, and rather less LED lighting than I expected. A good showing of triple (or even quad) glazing, eg from Russell, and other building fodder from glulam to roof fixings and insulation (such as STEICOzell blown pine wood-fibre), although maybe less aimed at self-build and more at professionals, I am not sure.

Unlike other 'eco' shows that I have visited, there did not seem to be any attempt to provoke impulse purchases (you cannot very well lug a 2-tonne thermal store home on the tube and then work out where to put it), and fewer dubious suppliers of 'snake oil' products and granite counter-tops.

There was lots of interesting technology to view, and senior people on hand to talk about it.

Almost the first thing to catch my eye was the PowerRouter grid-interactive inverter/backup, which at the simplest can be an uninterruptible power supply for your whole house. If you live out in the Styx and your grid power drops out frequently, this can keep you running from your microgeneration and batteries. The application I have in mind in minimising carbon footprint by shifting loads from times when the grid carbon intensity is high and/or when we are not generating from our PV, to when it is low such as in the wee hours of the morning. Nedap's Lithium-battery version (which would have the required energy efficiency in and out of batteries to be worthwhile from a carbon point of view) is under development.

Later on I found the Russell stand and had a chance to look at the Alu-clad triple-glazing, which requires no maintenance and thus given my level of attention a viable alternative to the uPVC double-glazing everywhere in the house already, much of which is old and with busted seals (ie misted up). Time to get a quote methinks...

I was pleased to see Romag at Ecobuild, and buttonholed their Technical Director, Kevin Webster, who has humoured me in the past putting together a quote for domestic double-glazing with some embedded PV for shade and generation in a west-facing room. It was good to see some of that style of glazing on display, but my eye was also caught by some 'colour' PV cells they were showing with a clever interference/diffraction layer on top which makes the cells appear (for example) a spectacular pink. Some efficiency is lost, and the cells cost more to prepare, but this opens op more aesthetic possibilities for facades or show-piece elements where the PV is a highlight rather than something to be hidden away.

Smart Isolator

Santon Switch Gear had a rather neat isolator box which is probably smarter than me, and will not let you open the box or unplug cables or do many other unwise things unless in the disconnected position. The AC and DC disconnects are interlinked too. Plastics engineering at its finest!

I spoke to Darius Kirevicius at the stand of 833 Solar showing off their Gallium-doped monocrystalline silicon PV. The use of Gallium (instead of, say, Boron) as a dopant drops the bandgap voltage a tiny bit and lines it up better with the received light spectrum, (thus improving efficiency) and adds some resistance to oxidation, from my understanding. Interesting stuff and I shall do some more research.

I gathered that Helios strategia wholesaled about 70MWp each of PV panels and inverters last year including maybe 3MWp/month of Panasonic/Sanyo HIT PV. That is into several EU markets, not just the UK by any means. From them, buying in bulk, one might hope for prices well below £1.30/Wp even for HIT kit.

Plug-in Solar (DIY/incremental PV system) had a neat scheme where you can assemble a system incrementally to dip your toe in without making a massive outlay, but I would be worried that they'd fall foul of G83/Part-P/FiT rules and at such time as you wanted to get it MCS accredited to receive FiTs the kit might not be counted as either new or MCS installed and thus might not be eligible. On the stand they did not seem clear and so this one is worth a little more research too, I think.