Ground source heat pump

[Ktelobb]

Can anyone tell me if you have to request planning permission for renewable energy? We are hoping to use a ground source heat pump and I notice on the LPA website there is a form to complete for Renewable Energy Advice? Is this just for advice or for permission? 
many thanks 

[SteamyTea]

You should not need any for a GSHP, but do the sums carefully as, generally, and ASHP is better.

And for that you may need permission.

[Ktelobb]

Thankyou but an ASHP won’t be suitable for us as we are building a fairly large house, we also have the land to be able to insert a GSHP 

[SteamyTea]

The size of the house, and the associated heat load, is technology neutral.  It is just a case of sizing any method of thermal generation correctly.

Have you done an estimate of your heat load?

Unlike most combustion boilers, heat pumps work best when then are over size.  This is to do with the output temperature.

There is a lot of stuff on here about sizing heat pumps.

Edited October 21, 2019 by SteamyTea

[PeterW]

15 minutes ago, Ktelobb said:

Thankyou but an ASHP won’t be suitable for us as we are building a fairly large house

I would caution making such a statement ..! We have members on here with 3-400sqm houses that are heated with 6Kw heat pumps as they have built in inherent air tightness and thermal elements that ensure the building requires very little heat load.  
 

What size are you building, and what is the construction method ..??

[SteamyTea]

1 minute ago, PeterW said:

Kw

kW

 

[Ktelobb]

Sorry, I am only quoting what we’ve been advised, our house will be 465sqm brick built 

[joe90]

2 minutes ago, Ktelobb said:

Sorry, I am only quoting what we’ve been advised, our house will be 465sqm brick built 

 

Yes but what heat load, what insulation, airtightness, glazing etc, this all dictates your heat load. My new build is brick built but almost to passive levels and it’s heated with a 4kW ASHP.

[Jeremy Harris]

8 minutes ago, Ktelobb said:

Sorry, I am only quoting what we’ve been advised, our house will be 465sqm brick built 

 

 

Worth seeking better advice, I think, as the installed cost of a GSHP will be very significantly greater than that for an ASHP, for a very tiny improvement in performance (probably around 5% to 10%, in practice).  Many have found that when the installed cost difference between the two is compared with the running cost saving through life the GSHP still ends up being a great deal more expensive.  For us, the installed cost of a GSHP was around three times the cost of an ASHP, and the few pounds a year it would have saved in running cost wouldn't even have covered the increased servicing cost that a GSHP installation incurs, let along the big difference in initial cost.

 

As @SteamyTea mentioned earlier, the heating technology used is unrelated to the size of the house.  An ASHP would work every bit as well as a GSHP, or pretty much any other heat source, come to that.

[Ktelobb]

Sorry, I am only quoting what we’ve been advised, our house will be 465sqm brick built 

4 minutes ago, joe90 said:

 

Yes but what heat load, what insulation, airtightness, glazing etc, this all dictates your heat load. My new build is brick built but almost to passive levels and it’s heated with a 4kW ASHP.

We are not at that level of detail yet, my original question was just ‘do we need planning permission’ ! Thanks anyway 

[Jeremy Harris]

Just now, Ktelobb said:

Sorry, I am only quoting what we’ve been advised, our house will be 465sqm brick built 

We are not at that level of detail yet, my original question was just ‘do we need planning permission’ ! Thanks anyway 

 

 

As far as planning consent goes, then generally no, it's not an issue.  For a new build, an ASHP isn't normally an issue, either, especially as planners are now realising that in most cases ASHPs are very quiet (my experience has been that a modern inverter controlled ASHP is a lot quieter than the two GSHP installations I've experienced).  Noise is a consideration, as all inverter controlled ASHP are now very quiet indeed, whereas there are still a lot of pretty noisy GSHPs around.  We spent a week on holiday in a place with a GSHP that was so noisy it kept us awake at night.  The owner of that holiday let has now relocated the GSHP away from the building, in it's own (soundproofed) shed, in an attempt to reduce the noise level indoors.

[joe90]

Sorry @Ktelobb, as @JSHarris says above , we simply indicated an ASHP on the plan to show where it was but no specific application was made and it was not questioned. I too have the space fir a GSHP but the sums and the amount of work just did not add up (and I have my own JCB).

[Ktelobb]

Ok thanks for the advice, we shall look into both options further 

[Redoctober]

1 hour ago, JSHarris said:

 

 

As far as planning consent goes, then generally no, it's not an issue.  For a new build, an ASHP isn't normally an issue, either, especially as planners are now realising that in most cases ASHPs are very quiet (my experience has been that a modern inverter controlled ASHP is a lot quieter than the two GSHP installations I've experienced). 

 

Again, worth checking as I know In Scotland PP is or certainly was required, back in 2016. 

[Jeremy Harris]

1 hour ago, Redoctober said:

 

Again, worth checking as I know In Scotland PP is or certainly was required, back in 2016. 

 

 

If retrofitting to an existing house, then PP may be required (seems to be often ignored here, though), but if it's a new build then adding an ASHP is a NMA.  My planning consent had no ASHP, as we were, at that time, going to install a GSHP.  When I realised just how much more expensive a GSHP was going to be over an ASHP, I called the planning officer and asked if I needed to submit a new application.  He just asked for an amended plan showing the location of the ASHP outdoor unit, then emailed me to say he'd made a note in the file that there was now an ASHP included.  No fee payable, no forms to fill in, just a phone call and exchange of emails.

[Ed Davies]

4 hours ago, Ktelobb said:

Can anyone tell me if you have to request planning permission for renewable energy?

 

In general, yes, but a lot of installations can be allowed by permitted development. What's allowed by permitted development and the exact conditions vary a lot between countries. England and Wales are pretty similar to each other, Scotland is significantly different. Not sure about Northern Ireland. If you're in England then this is probably where to start:

 

https://www.planningportal.co.uk/info/200130/common_projects/27/heat_pumps

[Judy C]

The unit needs to meet certain requirements to be considered permitted development and your supplier should be able to supply the appropriate information.  Listed buildings do not have permitted development rights.

 

As for GSHP - the RHI payment is double, so some of the additional cost will be paid for by that.  GSHP last longer and are more efficient.   And if you put the unit in a garage, completely invisible.

[PeterW]

23 minutes ago, Judy C said:

GSHP last longer and are more efficient.

That is a slightly subjective statement, and the bigger issue with GSHP is cost, both initial capital and TCO. Overall life and cost per useful kWh produced for ASHP (including RHI) is better than for GSHP. 

[Jeremy Harris]

I agree with @PeterW .  If anything, I suspect a GSHP will have a shorter life, at least between repairs, as it uses an extra circulating pump to move brine around the collector loop.  A GSHP also has ongoing maintenance costs that an ASHP doesn't, because of the need to replace the brine periodically (which is pretty expensive) and the need to inspect the brine filter(s).   I know of a couple of GSHP installations, and both have been very costly, both to install and to maintain. 

 

There doesn't seem to  be much of an efficiency improvement over an ASHP, either, AFAICS.  One issue is that, although a GSHP operates with a very slightly lower Δ_T, this only really gives any advantage when the outside air temperature is lower than the collector temperature.  So a GSHP may run more efficiently than an ASHP when the air temperature is lower than about 8°C, but will run less efficiently when the air temperature is above about 8°C.  Mean winter temperature in much of the UK may not be much lower than 8°C for around half the heating season, so a GSHP may well work less efficiently than an ASHP then. 

 

The cost comparison for us was pretty compelling.  I originally planned to install a GSHP, but the lowest installed price, with me doing much of the installation work, was going to be around £9k.  I purchased and installed an ASHP for about £2k.  The GSHP was predicted to run at a COP of ~3.6 overall.  Our ASHP runs at a measured COP of 3.5 on average.  The RHI payments (which we didn't bother with) were going to be £84/year for 7 years, so not worth having for the additional installation premium we'd have had to pay to get them.  The difference between the actual ASHP COP and the predicted GSHP COP would take a couple of hundred years or so in energy cost savings to recover, plus we'd have had to pay for the GSHP servicing, brine changes, etc, which would alone have cost more than the energy savings.