Ground Source Heat Pumps

ccbrowning

Anyone in a new build home that has a GSHP? Buying a place that uses one and am curious about potential running costs. Four bedrooms, and underfloor heating on both of the floors. 

EPC is just a high B, but that’s because it is marked down due to having the heat pump. 

Reed_Richards

The EPC should give figures for the annual energy requirements for heating and hot water.   Add the two together and divide by 3 then multiply that by whatever you pay per kWh for your electricity.  That should give you a somewhat pessimistic estimate of the annual running cost.

A ground source heat pump should give you the best energy performance you can get.  It's crazy if that causes a mark down.

ccbrowning

The EPC also recommends solar hot water as the only improvement measure (house has PV), so it’s obviously an odd one.  

See the ratings above? Only ‘average’ with underfloor + gshp. 

I think the numbers are made up, too:

beardymarrow

Yeah, you have to wonder what would good be, if GSHP with underfloor was average. I wonder if it's because they've incorrectly selected "electric" as well which it assumes means there are electric heaters (in addition to the GSHP)? 

shinytop

I don't think the EPC calculations take account of the COP of the A/GSHP. It just assumes it's electric heating which gets marked down because it's expensive.  Daft I know.

The numbers don't look unreasonable for a new build.  Whats the area/size of the house?

Reed_Richards

I would have thought with those numbers and UFH throughout you could reasonably aspire to an annual energy consumption of 3000 kWh.  Which should cost something like £630 at current rates and excluding the standing charge.  I should be so lucky.  

ccbrowning

shinytop said:

I don't think the EPC calculations take account of the COP of the A/GSHP. It just assumes it's electric heating which gets marked down because it's expensive.  Daft I know.

The numbers don't look unreasonable for a new build.  Whats the area/size of the house?

208 m2 over two floors. 

Does seem like the whole EPC system is in need of updates, tho. Perhaps you’re right about how it is interpreting electric. Sure, it’s electric, but using electricity to heat water, etc. 

ccbrowning

Reed_Richards said:

I would have thought with those numbers and UFH throughout you could reasonably aspire to an annual energy consumption of 3000 kWh.  Which should cost something like £630 at current rates and excluding the standing charge.  I should be so lucky.  

We will have to see. I spend more currently for gas and electricity in my current home, which was built in 2014 and has gas-heated UFH just on the ground floor. I’ll report once we’re actually in the new place and get some real numbers. 

beardymarrow

ccbrowning said:

shinytop said:

I don't think the EPC calculations take account of the COP of the A/GSHP. It just assumes it's electric heating which gets marked down because it's expensive.  Daft I know.

The numbers don't look unreasonable for a new build.  Whats the area/size of the house?

208 m2 over two floors. 

Does seem like the whole EPC system is in need of updates, tho. Perhaps you’re right about how it is interpreting electric. Sure, it’s electric, but using electricity to heat water, etc. 

Ours is a little bit bigger than that (230m2} and we only have UFH in half the ground floor. We're consuming 15000kwh per year in total (not just for heating and hot water) so I'd say the 3000kwh would be optimistic, but the 12000kwh from the epc just for heating and hot water does seem pessimistic. If you budget for 12000 you'll hopefully be pleasantly surprised. Time will tell as you say. 

Reed_Richards

ccbrowning said:

I spend more currently for gas and electricity in my current home, which was built in 2014 and has gas-heated UFH just on the ground floor. I’ll report once we’re actually in the new place and get some real numbers. 

So how do the EPC figures for your current place compare?