Preparing for Winter V

zeupater

kittie wrote: »

zeupater, what do you know about ground source heat pumps, apart from the expense? How big a garden would I need. I will be moving house and this is something I would seriously consider. Is it still efficient at temperatures of -15?

My `eco` rhi stove is wood pellet and there is a european wide shortage of the special pellets :mad: . I am allowed to use portable electric heaters and still get rhi but 10kg bags of these pellets are impossible to get at the moment and the situation may only get slightly better in summer

Hi

A good friend had a GSHP installed a while back and chose a coiled ground loop which takes up quite an area & made a real mess of the garden (understated .. it was wrecked!) as somewhere around 1000 cubic metres of soil needed to be shifted to lay, which took time to put right ....

We looked at a system (but didn't buy!) using standard parallel 'serpentine' trenches about 1-1.5m apart in a very well drained soil, and (from memory) would have needed around 100m of pipework/kWh.t ... we have a lawn which much larger than average which would take the required pipe-run, but most gardens just aren't big enough ...

You can go for vertical heat exchangers using bore-holes, but be prepared for a shock on the price. A(nother) friend had quotes for a heat-pump installation for his house in the middle of a village & it looked like the installer wanted to use the project as his retirement fund by (heavily) loading the drilling cost, not knowing that a number of the farming 'neighbours' had recently had new boreholes drilled for water supplies & had an idea of costs - of course, after the 'error' had been pointed out, the price came down considerably (>£10k reduction!) so it's worth looking into drilling costs before contacting anyone! ... anyway, that system seems to be working well too ...

Cheaper/simpler/less messy but (normally) lower efficiency option is to go for an ASHP system, but check the rated performance (COP) of the unit and only use an installer that really knows what they're doing as overall performance really does depend on total system design and set-up !

We have Log-burner, GCH, Solar Thermal, Solar PV and a small Air to Air heat-pump .... it might be useful to have a look at this thread on the G&E board to get an idea what a few of us are doing with PV & high efficiency small heat pumps to supplement other heat sources ... https://forums.moneysavingexpert.com/discussion/4715287

... as for performance at an ambient temperature of -15C, there shouldn't be much difference with a GSHP as long as that temperature isn't long-term as the ground is effectively acting as a solar thermal store. Many decent wet ASHP systems will work at -15C but there's a considerable reduction in performance ... there's a link to temperature performance charts for our unit somewhere in the thread link above if you're interested, but remember that it's a particularly high performing unit!

HTH
Z

[Deleted User]

thank you zeupater, I have changed my mind, none of these technologies are really financially worthwhile at my age, cost/ years. I don`t have a new home in sight yet but when I do will concentrate first on good insulation. We once had a det house, 50s I think, was freezing but hubbie was a structural engineer and quickly sorted external insulation, leaving that very important air gap. Rather different for me now and am assuming I may get a 70s house but I`ll see

tori.k

fuddle wrote: »

My grandma always wore a skirt and tights. I only ever saw her in slacks when she was going to travel. Her house was breeze block and very little else and was cold. There has to be something in skirts/tights for warmth.

So did an old boy builder we knew, he said he pinched his wife's old 70 denier tights when he was working as thermals were to hot

Wednesday2000

I'm not looking forward to it getting very cold!

Hot water bottles during the day and at night and I often wear leggings under my dresses as that help to keep me warm. I was wearing a scarf indoors when it was cold too!

I bought a halogen heater that I will use as well.

LadyhavershamLost

the small people are hunting for the hot water bottles in anticipation of the cold.....Not really had much need for them this winter - warm jim jams and fleecy blankets have been much used!
I thibk they night be at their dad's house - will have a hunt when I pop in tomorrow - (school uniform swap)

Am keeping a close eye on the weather sites.....

zeupater

kittie wrote: »

thank you zeupater, I have changed my mind, none of these technologies are really financially worthwhile at my age, cost/ years. I don`t have a new home in sight yet but when I do will concentrate first on good insulation. We once had a det house, 50s I think, was freezing but hubbie was a structural engineer and quickly sorted external insulation, leaving that very important air gap. Rather different for me now and am assuming I may get a 70s house but I`ll see

Hi

I agree on the insulation .... the cheapest form of energy is that which you don't need, so insulation is the priority .... we're really well insulated (eg ~500mm in the loft) and have very low annual bills, probably low enough to make some cry!! ..

You're right on the heat-pump front on a straightforward ROI basis, at the margins applied by (most) installers they make little sense if gas is available, but in remote areas reliant on oil or LPG they can be quite an attractive alternative. However, there is a scheme (RHI) which may help the figures, if you have a reasonable EPC rating the scheme helps by providing a level of support for a handful of years, so it may be worthwhile having a look into that before making a final decision, particularly if a Air-to-Water ASHP could provide a solution.

Our small heat pump is Air-to-Air and really high efficiency ... the idea is to run the unit mainly during the day during Spring & Autumn when there's plenty of sunshine & we don't need much heat other than to maintain indoor temperatures. This type of heat-pump isn't included within the RHI scheme, so there's no support, but they are a lot cheaper and normally a lot more efficient ... our unit is capable of providing around 6kWh of heat for every 1kWh of electricity used (COP6.0) if temperatures outside are typical for Spring/Autumn (~12-15°C), dropping to around a COP of 4.5 if it's freezing outside & around 3.5 at -15°C .... we're currently using it and it drawing ~370W & providing around 1.7kW of heat (-1C outside!) ... on our tariff it's still cheaper to use the heat-pump than gas in the evening when it's dark - it only has a heating capacity similar to a reasonable electric fan-heater so doesn't heat the whole house, but it's toasty warm where I'm sitting & the log-burner & GCH haven't been used for days & most of the day it's been running using our own solar generation, so for free! ...

HTH
Z

[Deleted User]

very interesting zeupater, I may be picking your brains re air to air in the future. At present I have an eco house PV, solar thermal, triple glazing, wood pellet stove. Impossible at present to get bags of pellets, european shortage so am temporarily using moveable electric heaters with thermostats.

What make of air to air do you have? I want to start keeping details in a notebook and I know you have done all the research

fuddle

The met office has issued a snow weather warning for us in the North East and Eastern side starting from Tuesday 3am. The weather models continue to produce charts that show it's highly likely that many parts of the country will have snow next week.

Any snow showers will accumulate and remain because there will be no chance of a thaw at all for the foreseeable future.

[Deleted User]

spot on fuddle you should be a weather presenter

Plus the snow underneath will compact and be frozen solid, will making walking and driving very dangerous as only major roads will be salted. If the snow plough goes through, like it did here in 2010, it further compacts the snow underneath and makes it much more dangerous again. A walking stick and crampons will help and an ice axe if living up a big hill . Roll over onto stomach and get your body over the axe, then dig it in as you slide. It will stop you but then you have to get up (imagine scrabbling legs) and you may be left hanging. Better get ready for cabin fever, it`s safer

I am bringing my makita batteries and charger into the house today plus my makita radio and makita lamps. Candles and matches are handy. Flask will be put on the countertop on sunday. All water containers in the freezer are solid, will add small ones today. Chocolate in store, biscuits made, plenty of books. Kindle fully charged and plug in phone accessible

mardatha

Already been dealing with it up north for a few weeks -
http://www.bbc.co.uk/news/uk-scotland-highlands-islands-43157972