Does PHPP Work ?

fclauson

Thought I would share this with you

PHPP for Jan suggested I would use 1086Kwh for the month (for heating) and
I used 330Kwh (approx)


using met.ie it says the average temp for my nearest station (Carlow) was only 0.1 above the average

so conclusion - house is performing much better than the PHPP model
Why - Don't know

sydthebeat

fclauson wrote: »

Thought I would share this with you

PHPP for Jan suggested I would use 1086Kwh for the month (for heating) and
I used 330Kwh (approx)


using met.ie it says the average temp for my nearest station (Carlow) was only 0.1 above the average

so conclusion - house is performing much better than the PHPP model
Why - Don't know

can i suggest that its because phpp defaults to the worst value on nearly all occasions??

Its completely different from DEAP in that respect where best values are encouraged.

fclauson

Good point - DEAP is giving 879Kwh

I have to own up - we did light the stove 4 or 5 times - but that will not account for the big discrepancy

Cooking, Parties, better Solar Gain, and talking a lot must have added the rest

sinnerboy

Solar gains may have been better in Wexford where you are than Carlow where the weather dataset is drawn from. Your internal gains maybe higher then PHPP calculates . 2 things off the top of the head....

sinnerboy

Nice "problem" all the same fc

fclauson

the model data for the house came from John Morehead - expert in exact local weather sets

As I have said in previous posts PHPP is mr average with a good spoon ful of being doomy and gloomy on data

over the next 20 years bet we will have a month where I use more than PHPP predicts

housebuilder1

Probably because you're using a fanatic danfoss heat pump there. Lol.
The you use a heat pump in your original calc or a boiler. If you used a boiler then it would explain the big difference.

Cavanjack

fclauson wrote: »

Thought I would share this with you

PHPP for Jan suggested I would use 1086Kwh for the month (for heating) and
I used 330Kwh (approx)


using met.ie it says the average temp for my nearest station (Carlow) was only 0.1 above the average

so conclusion - house is performing much better than the PHPP model
Why - Don't know

Just seen your house on passive house magazine. Looks the business.

fclauson

housebuilder1 wrote: »

Probably because you're using a fanatic danfoss heat pump there. Lol.
The you use a heat pump in your original calc or a boiler. If you used a boiler then it would explain the big difference.

all calcs based on a 9kwh HP which uses about 2kwh when running normally for UFH

fclauson

So I think I have made a mistake - the figure I quoted was primary energy used - of course I should have quoted energy output by the HP - which if its COP is 420% and this can be beleived moves the energy used up to 1300Kwh for Jan - which is now the wrong side of the PHPP calculation

Need to do some more measurements to check all this out

just do it

fclauson wrote: »

So I think I have made a mistake - the figure I quoted was primary energy used - of course I should have quoted energy output by the HP - which if its COP is 420% and this can be beleived moves the energy used up to 1300Kwh for Jan - which is now the wrong side of the PHPP calculation

Need to do some more measurements to check all this out

Looking at it another way 1,086/330 -> COP of 329%. This would still not be a bad COP for one of the two coldest darkest month of the year.