Domestic air source and cold callers

[Morrisman]

Aren't the f**kwits put on earth by God to give us pleasure. Best to bait them into believing that you are interested and get excited at the prospect of an easy sale. When they are just about to peak, tell them to bugger off. Next month they will be selling something different.

Like the door knocking guy with the Irish accent, who told me that any double glazing over 8 years old had to be replaced with triple glazing, by law...... He wasn't amused when I laughed in his face.

Mind you, at 63 I'm the youngest resident in my street, so I'm sure his social profiling training must have convinced him we are all impressionable old f***wits in our area.....

I should have asked him for a quote, now my addled old brain thinks of it.

 

[Morrisman]

Heat people not places. I don't think any of these cold-calling installers have any idea about building physics. I've done a successful heat pump installation based around low-temperature underfloor background heat, with radiant panels for smaller specific areas where sedentary activities would take place. People don't overheat in the active bits or freeze in the stationary ones. The central heating concept is a big problem to my mind and a massive efficiency issue. q

How about thermal body warmer vests, powered by induction coils in every room? Heat the person, not the room?

Mate of mine has an electric heated waistcoat for cold days riding his bike, reckons it is the best thing since sliced bread, powered off a small battery pack in the pocket.

 

[Greeves246]

How about thermal body warmer vests, powered by induction coils in every room? Heat the person, not the room?

Mate of mine has an electric heated waistcoat for cold days riding his bike, reckons it is the best thing since sliced bread, powered off a small battery pack in the pocket.

I used to put an old newspaper inside a Belstaff back in the 60s for insulation but I never thought about using sliced bread.

 

[waddycall]

So when the temperature is around zero, it's useless, no?

No, just less efficient. Ground source heat pumps have their efficiency (COP) measured with an inlet from the ground at 0C and return to the ground at -3C.

 

[brewdexta]

There will be very little difference in the design of a heat pump underfloor heating system and a boiler underfloor heating system as the limitations are the maximum temperature that the pipe will accept and the screed / floor covering maximum permissible temp. The upper limit for the PEX pipe is about 50 C so ideally suited for a heat pump flow which is probably about 45 C without any temperature reduction. When using a gas boiler as the heat source, the maximum flow temperature is limited at the underfloor heating manifold by either local mixing valves or direct boiler temperature control so that the maximum pipe temperature is not exceeded. The density of the pipes would be to suit the area heat loss and wouldn't vary between either source.

Max temp of Pex is 200f or about 96c. The boiler we originally used mixed down to a max of 55c and the return temo safety relay was set to 60c. It was an early boiler designed for UFH with mixing valves built in.

 

[Mikes]

Max temp of Pex is 200f or about 96c. The boiler we originally used mixed down to a max of 55c and the return temo safety relay was set to 60c. It was an early boiler designed for UFH with mixing valves built in.

For years we always fitted a high temperature shut off valve as well as the 3-port mixing valve just in case the mixing valve failed open to the boiler circuit. Most manifolds don't even have the mixing valve now when supplied direct from a condensing boiler set to 50 C flow. Now no one wants to fit the additional valve as they all think no one will ever turn a boiler up! At least with a heat pump you know it isn't ever going to get that hot.

 

[Gazz292]

wait, so i can't fit a 3Kw solar PV array to my west / east facing roof and be able to weld and run the compressor at midnight for free, damn

I am planning on fitting a solar PV array one day, got a small roof that's south facing, and i'd like to get rid of the conservatory and replace that with an extension, so i may just about have room for a 4Kw PV array,

But i'm keeping the gas combi boiler for heating, i might fit electronic thermostatic rad valves to make it into a room by room zoned system tho, got concrete floors, so not sure how well that'd work with an 'underfloor' heating system,


I always wonder why they don't have a combined electric and hot water solar panel,
Solar PV panels reduce their output when they are hot, so why not have a pipe snaking on the back of them and pump coolant through it, absorb the heat from the panels and lower their temps so you get more electric output (maybe) and use that heated coolant to heat a thermal store or something.

 

[minimutly]

The residents saved on average 40% on their previous bills

Well I suppose that's an achievement in itself. Doesn't help though, without knowing what they were spending before, and on what.

 

[fizzy]

wait, so i can't fit a 3Kw solar PV array to my west / east facing roof and be able to weld and run the compressor at midnight for free, damn

I am planning on fitting a solar PV array one day, got a small roof that's south facing, and i'd like to get rid of the conservatory and replace that with an extension, so i may just about have room for a 4Kw PV array,

But i'm keeping the gas combi boiler for heating, i might fit electronic thermostatic rad valves to make it into a room by room zoned system tho, got concrete floors, so not sure how well that'd work with an 'underfloor' heating system,


I always wonder why they don't have a combined electric and hot water solar panel,
Solar PV panels reduce their output when they are hot, so why not have a pipe snaking on the back of them and pump coolant through it, absorb the heat from the panels and lower their temps so you get more electric output (maybe) and use that heated coolant to heat a thermal store or something.

They do exist - quite expensive and prone to problems.

 

[minimutly]

They do exist - quite expensive and prone to problems.

A little pointless just to pick up 2 or 3 percentage efficiency points...
best way is to use an immersion heater and controller so when the sun shines you get free hot water. Oh no, wait, lady next door had hers ripped out by the ASH "engineers", then to cap it all the solar panel guys pinched the old copper cylinder, I had to laugh...

 

[AdW]

Whats the depth of a heat source borehole out of interest?

That depends on the type of system that you want to install and the ground conditions.

An abstraction well for an open system needs to get comfortably into the aquifer and for a domestic well, 10-20 m below the depth at which the pump will be set is common. Perhaps less in good productive rock. The level of the pump will depend on the standing water level, the pumping rate required and the drawdown of the water surface when pumping. If recharge from the aquifer is slow, you can increase yield by drilling deeper (giving you more storage capacity in the well itself) and a greater surface area for recharge, but you need to be careful not to overshoot the aquifer into unproductive ground or into poor quality groundwater.

Groundwater in your well may be resting 25' down, but that might not represent the depth of mobile groundwater in the ground - it could be coming in from fractures or more permeable strata deeper in the well and just rising to rest at that level. A quick look at the expected geology would inform on the likelihood of that. Feel free to DM me your location.

Closed system boreholes may be shallower or deeper! That will depend on the number of linear meters of thermal loop required, the space available and the nature of the ground/groundwater regime. My experience of drilling contractors installing thermal loops is that they will only commit to install XXm total, this is to cover themselves in the event that a loop gets hung up in the hole and can't be persuaded further in or recovered - you can end up with more but shallower loops than intended. 100m deep holes are not uncommon.

 

[Kayos]

Well I suppose that's an achievement in itself. Doesn't help though, without knowing what they were spending before, and on what.

Electricity, it doesn't matter if you spend £2 or £200 a week, 40% is 40% and a significant saving

 

[Kayos]

That depends on the type of system that you want to install and the ground conditions.

An abstraction well for an open system needs to get comfortably into the aquifer and for a domestic well, 10-20 m below the depth at which the pump will be set is common. Perhaps less in good productive rock. The level of the pump will depend on the standing water level, the pumping rate required and the drawdown of the water surface when pumping. If recharge from the aquifer is slow, you can increase yield by drilling deeper (giving you more storage capacity in the well itself) and a greater surface area for recharge, but you need to be careful not to overshoot the aquifer into unproductive ground or into poor quality groundwater.

Groundwater in your well may be resting 25' down, but that might not represent the depth of mobile groundwater in the ground - it could be coming in from fractures or more permeable strata deeper in the well and just rising to rest at that level. A quick look at the expected geology would inform on the likelihood of that. Feel free to DM me your location.

Closed system boreholes may be shallower or deeper! That will depend on the number of linear meters of thermal loop required, the space available and the nature of the ground/groundwater regime. My experience of drilling contractors installing thermal loops is that they will only commit to install XXm total, this is to cover themselves in the event that a loop gets hung up in the hole and can't be persuaded further in or recovered - you can end up with more but shallower loops than intended. 100m deep holes are not uncommon.

Deepest we did was 300m, referred to as medium depth

We only pay drillers for completed loops, if it's 100m short they will be £4k down

More shallower boreholes doesn't always work as the pressure drop on the system becomes too high, the ground side pump can only consume 3% of the units total power so is limited in size

 

[minimutly]

Electricity, it doesn't matter if you spend £2 or £200 a week, 40% is 40% and a significant saving

Damn you can be a stubborn so and so sometimes.
It does matter, since the whole point of the post was to highlight these cold callers telling people they would be saving money on oil heating. But since you don't know, that's that. No one is doubting you're savings, but, oh I give up...
Actually I will say that 40% of £2 is actually, buggerall....

 

[Kayos]

Damn you can be a stubborn so and so sometimes.
It does matter, since the whole point of the post was to highlight these cold callers telling people they would be saving money on oil heating. But since you don't know, that's that. No one is doubting you're savings, but, oh I give up...
Actually I will say that 40% of £2 is actually, buggerall....

I'm just tired of the drivel posted about heat pumps

Sign an NDA and I will share the full M&V report for one of my projects

There is a reason I can't post specifics, but if you sign the NDA, then neither can you

 

[minimutly]

I'm just tired of the drivel posted about heat pumps

Sign an NDA and I will share the full M&V report for one of my projects

There is a reason I can't post specifics, but if you sign the NDA, then neither can you

Thanks. As posted above I have no reason to doubt your claimed savings, but I would dispute any claims that a single dwelling domestic system will outperform (on running cost terms) an existing oil system. Until someone can post these numbers I remain sceptic.
Thanks.

 

[minimutly]

Fizzy,

Dinorwig @ 9.1GWh is 4 times the capacity of this battery? (no ‘/‘ in GWh, btw - no such unit as GW/h)

The single advantage of a battery is the response time - Dinorwig takes about 20s if the turbines are already spinning (probably a minute, if not). Dinorwig can supply 1728MW - nearly half a GW than this battery (without extra upgrade to the grid connection)

Ffestiniog pumped hydro can add another 360MW with a capacity of nearly 1.5GWh. Both those installations will be working long after the battery has been changed a few times, Inexpect,

Even so, this battery is yet another aid to avoid power outages, balance the grid and act as an energy store. Another piece of the national grid supply.

It could never supply enough power to run the whole grid - even for one second, so the 3 1/2 minute ‘analogy’ is a joke. What Scenario can you foresee where all of the UK power would need to be replaced within a few seconds? We now have nuclear plants as base load as well as fossil fuel generation as dispatchable output. Only the renewables are not quite as predictable - but are quite well forecast most of the time. Then there are umpteen HVDC International connectors.

So what is your problem? I don’t see it, the National grid don’t see it. Only you and a few others cry about it.

I’ll tell you about an issue I’m seeing occasionally, as a result of the slackening of the regulations around disconnecting from the grid if it fails -
So originally the G59 regulations were really tight and the dno s if anything pushed them tighter, so when there was a grid brown-out, or a fault somewhere out there far away, the turbine, or whatever you had turning the generator would trip. After a time it would auto reset, provided you have designed the system correctly.
Now we have been told to modify the settings to a new g59/3, or for new sites g99. This massively relaxed the settings to prevent another outage such as happened in the south east around 4 years ago. All hunky dory then? Actually no, what I’ve seen is we are getting occasional current overloads, taking the generator ACB out. This does not reset. To date I’ve never identified a fault for this - so what’s going on?
Well here is my answer - when we now get a brown-out, rather than an auto resetting trip the turbine (and generator) keep on spinning. Now in theory thengenerator, being a rotating machine must stay synced to the grid. However, if the brown out is long enough, and deep enough, the turbine will start to speed up. Result? An out of synch generator, when the grid comes back up.
This has now happened enough times on various sites for me to be pretty sure that this is correct. Happily, inverter machines hooked up to batteries (some wind turbines also) do not share this speeding up characteristic, but for turbine generators I believe it’s a major issue.

 

[gaz1]

from some info it would be the opposite way

to make a grid fully collapse is to hurt it at the high point of generation between 4-6 when everyone is getting home

so if everyone in the uk sick and tired of the energy bills all turned off there power at full tilt they would cause alot of damage as the grid has been powered up to provide this power at this time, if it has no where to go

it will start to blow transformers, substations as they will start to over heat as power is still being produced, the electric power generation boards will be screaming at them to shut things down

mps and others have suggested a time of 10pm of everyone shut off there power at this time but that wouldnt cause the damage to teach the energy suppliers a lesson

once the transformers and substations start tripping out its going to be a while before power is restored

only at reconnection would anyone thats suppling the network be out of synch from a black out therefore during a black out you should disconnect from the grid to stop power being pulled from your system

otherwise theres a high chance you would receive an energy spike down the grid due to being out of synch with the network

 

[willie.macleod]

from some info it would be the opposite way

to make a grid fully collapse is to hurt it at the high point of generation between 4-6 when everyone is getting home

so if everyone in the uk sick and tired of the energy bills all turned off there power at full tilt they would cause alot of damage as the grid has been powered up to provide this power at this time, if it has no where to go

I think the chances of getting enough folk to engage with this destructive idea is minimal, given the choice between making a protest or having their tea most will choose tea....

 

[fizzy]

Fizzy,

Dinorwig @ 9.1GWh is 4 times the capacity of this battery? (no ‘/‘ in GWh, btw - no such unit as GW/h)

The single advantage of a battery is the response time - Dinorwig takes about 20s if the turbines are already spinning (probably a minute, if not). Dinorwig can supply 1728MW - nearly half a GW than this battery (without extra upgrade to the grid connection)

Ffestiniog pumped hydro can add another 360MW with a capacity of nearly 1.5GWh. Both those installations will be working long after the battery has been changed a few times, Inexpect,

Even so, this battery is yet another aid to avoid power outages, balance the grid and act as an energy store. Another piece of the national grid supply.

It could never supply enough power to run the whole grid - even for one second, so the 3 1/2 minute ‘analogy’ is a joke. What Scenario can you foresee where all of the UK power would need to be replaced within a few seconds? We now have nuclear plants as base load as well as fossil fuel generation as dispatchable output. Only the renewables are not quite as predictable - but are quite well forecast most of the time. Then there are umpteen HVDC International connectors.

So what is your problem? I don’t see it, the National grid don’t see it. Only you and a few others cry about it.

We hardly have any nuclear left that's the problem!. What picks up the slack? Gas. Gas power stations are expected to just "switch on" hence why our bills were so high when gas prices shot up. Many people - and the politicians- actually seem to believe we can go 100% renewables and use batteries to pick up the slack for 10 days in Winter with no wind. Never going to happen! Germany also seems to think they can go all out for renewables when in fact, instead of gas, they burn loads of filthy lignite instead.
If we want to be serious about cutting CO2 we need to stop burning fossil fuels and go all out for more nuclear like France. People like Putin and the Arabs can't hold a gun to our heads then either.