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Steve Pester, BRE, reflects on the increasingly attractive prospect of BIPV

An interesting conference on Opportunities in Building-Integrated Photovoltaics (BIPV) was hosted by the Knowledge Transfer Network a few weeks ago.

When I first saw the invitation, I thought that to host such an event was a brave move, given the state of the BIPV market during the last five years. We have seen prolonged and fierce competition amongst module manufacturers, many of whom have gone to the wall, coupled with austerity measures at home and abroad. Against this kind of background, BIPV is often considered to be something of an unnecessary luxury. But it is not just that.

There seems to be a lack of understanding amongst non-industry people about what BIPV actually is; many assuming that panels on a frame on a roof must be ‘building-integrated’. Once you have cleared up that misunderstanding, there’s the range of BIPV product types to explain: roof tiles, glass facades, façade infills, windows, atria, sunshades, etc. The whole thing is rather complicated unless you are in the business.

Can architects help? Well, it is their reputations on the line if a roof covering lets water in or changes colour after 12 months, so with little information on BIPV as a reliable building product, who can blame them if they are not rushing to specify it?

The cost issue is partly perception (standard PV ‘payback’ calculations are not appropriate). BIPV will always be more expensive than standard modules, but the recent falls in the price of PV grade silicon mean that some BIPV products have also seen price declines. The new generations of PV materials, whilst yet to prove themselves in a conservative construction industry, promise even larger cost savings.