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PV In The SAP Calculation

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#1 vijay


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Posted 07 April 2016 - 04:17 PM

My plans have had a pass on the SAP calculations but they've asked if I want to include the PV panels as they are not needed to get the pass.

I doubt very much there would be anything worth it with a FIT t as the installation and return would be make that dead in the water. But I'm still hoping PV will be a worthwhile thing to have if I learn to use as many devices as I can during the day and also to heat water. Maybe PV batteries will be the next big thing too.

So should I include them in the SAP calculations? Is there any downside if I include them and then not install them in the future?



#2 Alphonsox


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Posted 07 April 2016 - 04:25 PM

It sounds like you have submitted the "planned build" SAP. You will need to submit a second "as built" SAP at the end of the build anyway which is what your EPC will be based on. If the two SAPs differ by a PV array then there won't be an issue as long as you still meet the base energy efficiency requirements.

#3 jsharris


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Posted 07 April 2016 - 04:40 PM

If you're going to fit them, then there is a slight advantage if including them in a new build, because there's no VAT, rather than the reduced rate 5% VAT. They will improve your SAP EER and EI, which may or may not be significant. Right now there's no value added to a house for having a high energy efficiency rating, but that may change in the future, it really depends a great deal on energy cost, and how that may change over time.

There's no downside in SAP terms in not including PV now, if you can get the DER below the TER without PV then that's all building control will be interested in, they don't usually care too much about the actual EER and EI rating, but some lenders (notably the Ecology Building Society) do attach importance to the EER, in fact they have refused to lend on builds with an EER below A100, which demands some form of renewable generation to achieve.

If fitting PV to a new build there are three potential installation cost savings over fitting it afterwards. The first I've mentioned, the small saving in VAT (which could be a greater saving if solar panels attract full rate VAT in future, as has been rumoured). The second is that you can fit the panels in the roof, which is neater and saves the cost of tiles/slates in the area where the panels fit. Finally there is a saving in scaffolding cost if fitting them from new, as the scaffolding will be in place for the roofers. If fitting panels afterwards then the cost of scaffolding would be incurred again.

Edited by jsharris, 07 April 2016 - 04:40 PM.

#4 vijay


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Posted 07 April 2016 - 05:32 PM

Thanks guys. I didn't realise there's another SAP test at the end but I guess it makes complete sense.

I plan to fit them and even more reason to do so now rather than later, so thank you :)