@editor

Thanks Mars...Our system is made by Grant and will be a 17kw unit. We are also looking at PV and battery storage to hopefully offset some of the increase in electricity use. I will update the forum as the installation progresses.

Regards Chris 

@chris-richardson I’ve been thinking about the grant one as well, i was recommended the Ecodan 14kw but i was concerned that my potential installer talked about it being close which tells me that the thing would potentially be working at full power all the time just to meet demand ! The 17kw feels like a better fit for me ! 

Hi, I'm Chris from Kemnay 😀 just outside Inverurie about 20 miles from Aberdeen.

We have a 1966 ex council semi (with a huge garage) which we've been slowly been modifying since we arrived about 15 years ago. It has a 5m single story,flat roofed  kitchen extension at the back and the old kitchen is converted into a third bedroom.

First in 2008 we added underfloor heating as 1. I'd just "underfloored" our old house a Victorian place in Boscombe. 2. the large rads and the number of them were taking up so much room in what felt like, after Boscombe, a small house. The kitchen extension was 1970's so had a concrete base a 6 in air gap and then a suspended floor. Perfect for UFH.The rest of the ground floor was suspended floor but with a good depth of crawl space underneath. Removing the old insulation was the worst..lying on your back with the old glass fibres getting everywhere.. but we managed to run the 16mm UFH heat pipes in 4 zones under the floor and tacked them next to the joists. I'd seen on a TV programme  Home designs, about multi layer foil insulation called Tri Iso and bought 4 rolls of this to staple to the joists and create a mostly draught free area for the UFH to operate in. This worked fairly well for 15 years.

The response time was fairly good and the house fairly warm but I knew I'd eventually have to do something better, so in 2017 my brother and I re designed the ground floor including lifting all the floor boards and removing, carefully the old Tri Iso. We replaced it with sterling board and on top of that we added black plastic sheeting, then 200mm of polysterene insulation then we clipped the existing pipes into place and covered them with kiln dried sand (Homebase even tried to sell me KD sand that they'd stored uncovered outside!!!)  and laid engineered oak boards over that. the result is that whilst the heating timew isn't as quick as the pipes in air, the heat storage and release is longer and thus works better for an even temperature. Its a bit of work to do, but if you're renovating the house anyway.. you may as well. the only thing I would have changed was to use pipe in plate instead of clips,, where the pipes are clipped into aluminium plates to aid the heat transfer.

The next thing (in 2009) we did was solar thermal as that was relatively "easy" to do. 20x 42mmNavitron tubes. It involved digging out a 3m x1.5m x1.5m hole under the floor as our little house didn't have enough room for a tank, unfortunately that meant a 3m run from the panel to the cheap 120 lit unvented single coil tank. we ran the hot feed into the cold feed of out Baxi 105e which worked really well, the combi no longer had to heat water from 5 or 6 degrees more often than not it was about 18c in the winter before the boiler ould start to heat it. The solar thermal has evolved by adding tubes in various combinations until now we have 1 x20 56mm and 2 x 10 56mm Navitron in a square runing into a 250lit twin coil Power flow copper cylinder (copper to kill Leigoinella and higher thermal transfer properties) with extra insulation. (made by McDonaldEngineers) With the initial stainless cylinder acting as a heatsink (and feeding the big tank)  if the big cylinder gets above 75C ish with a remote sensing TRV style diverter. We plan to add power to the older tanks immersion  and use Agiles plunging tariff with an IFTTT switch to heat that tank when the price is below 0P removed link

The thermal works really well and this winter have always had water above 20C base temp, measured at the hot flow pipe and of course this reduces the workload on the heat pump so that if we do have water below 30c af the hot flow pipe on top of the tank in the evening when we go to bed, we'll just push the button to let the heat pump do its work overnight. As Summer approaches we need to do that less and less. Cost wise, if you have enough roof and internal space for the tank and routeing the pipes, It's much cheaper than solar PV probably about £1500 for a small setup. Our setup over 10 years has cost £3932.69 but that includes the 250lit tank which was £2500, but worth every penny as the heat stays where it should be, in the tank. (and of course there's the RHI at £107 a quarter.) chose Navitron tubes against flat plate as they are much more efficient from almost 180 degrees whereas the flat plate only have the slight advantage of perhaps looking nicer.

In 2018 after I retired we added 5.6kWh of Solar PV to the garage roof (45 degrees bearing 144 magnetic) runing a Fronius primo 4kWh inverter into a Victron multiplus and CCGX and together with 2 x 2.2kWh of Aquion salt water batteries our initial setup was complete.

However we soon realised that in the Summer the PV wasn't like the Thermal and didn't continue to produce power into the afternoon (the thermal will produce heat on a good day even after the panels are in shadow) The drop off at 1300 was amazing. The inverter is limited to 4kW but drops to 2 kW in an hour and a further kW by 1500 and by 1700 is only producing 7-800w.

We decided to put panels on the other NW facing roof of the garage but faced the additional cost of a DNO aplication and another inverter. so we initially went with a compromise 4x 333w panels charging the batteries directly and not needing the extra expense and wall space ( which is in short suply at the moment) of another inverter and the paperwork of DNO application. I managed to pick up another 3 x second hand Aquions from Kent giving a theroetical 11kWh storage capacity ( I think, because they had about 3000 cycles on them the actual storage is about 8-9kWh) so now for 4.5 hours charging on the cheapest Agile rate I get most if not all day use on the cheap rate.  Screenshot below of the last 4 days load shifting.

During the building work a couple of years ago we insulated the dormers and roof and "stupidly" allowed the builder to choose the dormer windows. with hindsight this was a big mistake and now face the probability of replacing them as they are the place where the heat loss and cold gain happens and as a result the top floor never gets above 18c in the winter unless the sun is shining. We also had a Samsung 9kW version 5 Heat Pump installed to replace the gas boiler and had the big cylinder put in at the same time. That has worked fairly well, although we have never got the advertised 55C out of the heating side of it and the temperature drop in the 3m between the pump and the UFH manifold is about 7C. but with the few days of -15C this year and  the fact that we haven't had to run it H24 yet has given us the confidence toremove the (safety net) disconnected gas boiler from the wall as we don't think we will need it.

Heap pump was bought using the home energy Scotland loan and get enough RHI to pay for the loan, so it effectively costs nothing and it is much cheaper to run than the gas boiler in

2010 we used 9774 kWh of electric and 18000kWh gas costing £1524 (with 2 kids) in

2017 4450 and 15000 costing £1009 (no kids)  in

2020 we 5544 and just 200 and £720

Thanks to the RHI the solar is in profit next year

The heat pump saves money over the gas and so I regard it as being in profit now as the outlay loan is being paid by the RHI.

The Solar PV is a little more difficult to determine. If I take purely cost and income it will be in profit 2033. But the batteries are allowing me to load shift to such an extent that every day, well every day but 1, I have saved over the standard Octopus tariff regularly 7-10p and sometimes as much as much as 19p! So, I reckon perhaps 2026/27 I will be in profit with that

The next thing to do is to replace and extend the kitchen. It's built with 6in breeze blocks laid on their side so a solid wall with little insulation on the inside.

This Autumn we're going to replace and extend using SIP panels and triple glazed windows which with replacing the windows upstairs will mean we finally get rid of all the draughts and cold spots.

Next year the plan is to underfloor heat the room above the garage, from the Heat pump and create enough wall space to enable the 2nd inverter and associated PV.

Sorry its so long and apologies for the spelling mistakes.

Oh and I almost forgot. Last year I took the plunge and went electric with transport as well. I took advantage of the Scottish goverment interest free loan and bought a Model 3. thats costs £480 a month and about 5p a mile to run over the winter and 2p a mile in the summer where I use excess PV to charge.

I hope this is of use to you.

Greetings green fellows 🙂

I am Julian and been contributing to Mars YouTube and previous forum.  I am married to Jackie.  We have a 21 year old daughter.  Moved to current new bungalow 20 years ago.  We had 4kW of solar PV 9 years ago.  Best investment ever. Following our first smart meter, we have reduced our electric usage from 5500kWh to 4500kWh to about 2700kWh when the PV arrived. We added a Solic 200 electric diverter fitted to heat h removed link

We've gradually improved the building fabric.  With 300mm of loft insulation.  And triple glazing - we have a lot of glass - the home is supposed to look like a glass house.  We have glass roof in the sitting room and dining room, which was replaced with a more thermally efficient one 5 years go.  Since we heat with oil (new oil boiler 7 years ago), these changes have reduced our oil consumption from about 2000L annually to somewhere between 1200-1500L.

2 years ago we swapped my wife's Mini Countryman mk1 for a PHEV mk2 model.  We had a Zappi mk1 charge point fitted.  Having only driven about 10,000 miles, we estimate 8,000 of those miles to be pure EV (yes we haven't been far with Covid).  This convinced me when I sold my Mini JCW to buy a pure EV - a Honda e.  The Mini is on a lease and will be replaced by another pure EV - have a deposit on the new Ioniq 5 type 45.

And I have placed an order to replace our oil boiler with an ASHP from Daikin.  An 18kW model, with a Mixergy h/w cylinder (still investigating), this will mean the home is fully electric.

I look forward to lots of green and low carbon discussions

Hi Peeps, Ian Chapman here, gas enginneer looking to expand my knowledge on all things green.

😎

Welcome @idchappy, great to have to have you here. 

Hi I’m new looking for info on if air source heat pump is right for us . Thanks 

Welcome @nredshaw. I'm sure we'll be able to give you some information to help you, but you'll need to post some more information about your location and your house.

Chris

@nredshaw Hi and Welcome and as @Chris-in-kemney said we are happy to share our experience and advice but if you let us know what your current setup is and what you would like to achieve then we can help point you in the right direction look for the section marked ASHP 

Welcome to the forums @nredshaw. As the guys have said, please start a new topic here and we'll be happy to answer your questions: https://renewableheatinghub.co.uk/forums/renewable-heating-air-source-heap-pumps-ashps

@editor thanks for the welcome all I’ve posted in the ashp section hope it in the right place move it if it’s not and if you need any more info or pictures sent to pm etc let me know thanks all 

@nredshaw, it's been posted in the right place. Will have a look at your questions in detail tomorrow and reply.