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57 minutes ago, Lord v said:

The other common issue with retro fit is radiator size - as they operate at lower temp you need larger emitters

In our case the heat pumps had separate internal 'false ceiling cassettes' (Daiken).  The big elephant in the room is simply that electricity costs roughly 5 times as much as gas per KW (or allowing for a gas boiler inefficiency about 4 times as much).  Heat pumps are (roughly) about 3 times better than basic electricity ........ so end up still slightly more expensive than gas.

 

1 hour ago, Lord v said:

Although more expensive the Ground source would be the way I would go personally

I agree - and looked at it for home but ........ although I have the area, the installation costs for the 'collecting pipes' was huge - and likely to be plagued by tree roots - and the trees are subject to preservation orders.  In addition, I have (because I live in quite a remote village) only an 80 Amp (about 20 KW) total electricity supply and only single phase.  To increase that and go 3 phase was very very expensive.  Then - at current prices (against mains gas)  - it was going to cost more to run and be very very expensive to install ...... so all round - a non starter.  I do have approx 30% oversize radiators because the (condensing gas) system was designed to operate at a flow temp of 55 - 60C - which works fine for all but the very coldest and windiest of weather.

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The problem with all these schemes IMO is they work reasonably well in small scale pilots but cannot be scaled up

Electric cars fall into that category, is there enough lithium in the world? what are the environmental implications of mining it?

they have just started mining lithium behind where we live in Cornwall. When I asked a local councillor how they got permission he said "money talks" there is a global shortage. So that bodes really well for the long term plans doesn't it?  

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1 hour ago, JohnfromUK said:

In our case the heat pumps had separate internal 'false ceiling cassettes' (Daiken).  The big elephant in the room is simply that electricity costs roughly 5 times as much as gas per KW (or allowing for a gas boiler inefficiency about 4 times as much).  Heat pumps are (roughly) about 3 times better than basic electricity ........ so end up still slightly more expensive than gas.

 

I agree - and looked at it for home but ........ although I have the area, the installation costs for the 'collecting pipes' was huge - and likely to be plagued by tree roots - and the trees are subject to preservation orders.  In addition, I have (because I live in quite a remote village) only an 80 Amp (about 20 KW) total electricity supply and only single phase.  To increase that and go 3 phase was very very expensive.  Then - at current prices (against mains gas)  - it was going to cost more to run and be very very expensive to install ...... so all round - a non starter.  I do have approx 30% oversize radiators because the (condensing gas) system was designed to operate at a flow temp of 55 - 60C - which works fine for all but the very coldest and windiest of weather.

Did you ever look at borehole installation of the ground loop? Although the drilling isn't cheap it's quicker and less disruptive. Just one 150mm hole about 70m deep will do the average house. If mains gas is readily available though it will never really stack up.

If I was given free range I would be pushing ground source heat arrays. As long as you don't over saturate the ground then they are more staple than a PV field and require far less maintenance. 

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Just now, Lord v said:

Did you ever look at borehole installation of the ground loop?

No, but as you say, with mains gas available it was really a 'no brainer'.  I also need a quite large power (present gas boiler is 42KW) and to get that with heat pumps is £££.  PV is not good (listed building) and surrounded by trees.

In a few years time heating and looking after older and listed buildings is going to be a big problem.  You are very restricted in what you can do - and insulation is only practical to a certain extent (walls in particular are not practical to insulate, and air leakage (drafts) are very hard to eliminate whilst keeping the ventilation necessary to prevent condensation and wood rot.  Many older buildings are very vulnerable to rising humidity and dry rot if ventilation is inadequate.

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13 hours ago, Vince Green said:

The problem with all these schemes IMO is they work reasonably well in small scale pilots but cannot be scaled up

Electric cars fall into that category, is there enough lithium in the world? what are the environmental implications of mining it?

they have just started mining lithium behind where we live in Cornwall. When I asked a local councillor how they got permission he said "money talks" there is a global shortage. So that bodes really well for the long term plans doesn't it?  

Give the miners a heads up - there's big buckets of tungsten ready for picking just north of Plymouth which would do us far more good than lithium. :good:

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14 hours ago, JohnfromUK said:

No, but as you say, with mains gas available it was really a 'no brainer'.  I also need a quite large power (present gas boiler is 42KW) and to get that with heat pumps is £££.  PV is not good (listed building) and surrounded by trees.

In a few years time heating and looking after older and listed buildings is going to be a big problem.  You are very restricted in what you can do - and insulation is only practical to a certain extent (walls in particular are not practical to insulate, and air leakage (drafts) are very hard to eliminate whilst keeping the ventilation necessary to prevent condensation and wood rot.  Many older buildings are very vulnerable to rising humidity and dry rot if ventilation is inadequate.

Yeah that's not a small boiler... 

Historic buildings are going to be a nightmare - under the current regs you get a free pass if the building is listed or historic but I don't know if that will continue (it certainly should). 

As you say - these buildings were 'designed' (or rather built on the premise) of far leakier (and in some cases damper) construction. Simply insulating by blocking up the gaps with insulation really isn't going to solve the problem and will almost certainly make the problem worse. 

Come up with a good solution to that and this time next year we will be millionaires Rodney.....

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