Very impressive well done
Super stuff, for me it's not about a statistical improvement or even reduction of bills, it's about comfort. After 20yrs of attacking our 1970's semi the house is cosy, comfy and never cold, plenty of hot water on hand with minimal resources now needed to achieve this.
Just chatted with my BER assessor and he said that before the PV panels I was at A2 around 35 kWh/m2/year. When he added the PV panels it brought me from A2 to A1 and to -3kWh/m2/year.
I think the amount of I have also made a big difference 6.1kWp
D1 to B3 with a 6.84kW install.
Was that the only upgrades you had done since the previous BER assessment?
Originally a G, but have done several upgrades since then (over 6 years). Swapped out the storage heaters for an oil/solid fuel heating system with smart controls, led lights everywhere, new composite front door and pumped the walls with insulation, being the main jobs.
I asked the assessor if he could give me a provisional rating without the PV which was a D1, and the PV brought it up to the B3, but only just.
Really only another couple of inches of insulation to the attic is all that's left to do without spending a fortune.
We did a deep retrofit in 2018 on our 1930s terraced house.
Started with an icy cold D2 (267.6 kWh/m2/yr)
Thoroughly insulated, removed gas and fires, added heat pump and ventilation; which brought us to an A3 (66.96 kWh/m2/yr)
About to get a 5.85kw PV array, which should, based on the DEAP calculations mentioned earlier, bring us to an A1 (22.71 kWh/m2/yr)
Last BER rating was a C3. Since then, got new composite door, upgraded heating controls (zoned and better timing, etc), more efficinent grant vortex boiler, got rid of the electric shower, wood pellet stove (instead of multifuel). Am sure a 4.4kw system with Eddi will bring that up to the B's.
Mine went from D1 to B3 - 4.2kw E/W array+4.8kwh battery+ eddi water heater + newish gas boiler
Do ye pay the BER assessor fee each time you get some work done or is it 'part of the deal'? How much do they cost these days?
Mine cost €230 a few weeks ago in the midlands.
mine was €230 done on 03 May . (Mayo) Price was based on size of house .
Yeah €240 here in Cork a week or two ago
€380 for mine 😮
Pv is a great way to lift your BER because you get the benefit of the electricity energy Conversion factor of 2.08
Which means that every 1kw of electricity provided to the dwelling you get 2.08 of energy lift from it.
Like the opposite of how a storage heater apartment is cruxified due to its electric heating
10 bed house 😁
I recently got a new BER done post PV install. I have no idea how they do the calculations but went from a C1 to an A1. Cost was €195. No idea how it jumped that much or how the calculations were worked out.
What size PV system did you install?
7.2KW system.
And was any other work done apart from the Solar PV install?
Capped an open fire chimney apart from that nothing else.
Damn that's insane. I have C1 rating as well but they recommended 3.5 KW system. With all other changes I should expect A3.
Imagine if I got the other 3 wings done 😜
7.2 kw system, assuming 35 degree roof facing directly south, will be providing 6186 kwhr/y delivered energy to the dwelling.
This equates to 12,867 kwhr/y primary energy uplift.
That might be enough to bring a standard sized house from a C1 to an A3... but to go from C1 to A1 is quite incredible.
Well done but that just does not make sense, no point in going down a rabbit hole on it, the initial BER must have been way off is all I can think of
7.2kwP, surely the inverter would be the proper measurement point, a 6kW inverter can only do 6kW not 7.2kW.
There's actually the BER formula buried somewhere in this forum for PV improvement
I was quite quickly put back in my box when i said that you cannot have more solar than what the inverter is rated at. I was told it was very much possible, and I was shown a screenshot of same.
First off, ive used the BER formula to come up with the figures in my post.
im not sure what you are referring to above though.
im not suggesting a 7.2kwhr system is providing 12.8 kwhr electricity to the dwelling.
what im saying is, when it comes to the BER system, a 7.2kwhr system is calculated to provide 6186 kwhr/yr to the dwelling, and this benefits from the Electrical energy conversion factor of 2.08 ... so in the BER system that gives an energy uplift of 12,867 kwhr/yr and is the main reason PV systems give such significant BER uplifts.
Fantastic thread, some great info in here. We have a 70 year old mid terraced house that we have done alot of work / modernising to and brought it from a D2 to a C2.
A 4KWp system installed last month looks like it brings us close to a B3 (when included with 3 blocked / capped chimneys). External insulation in September brings us up to a high B1. Had hoped to break into the A's but that looks a stretch too far.
Question: I see reference to the "Electrical energy conversion factor" of 2.08. Should i be applying that to the output of the equation i.e. (0.8 x kWP x S x Zpv) x 2.08?
where did you get figures in your table?
