No way way too high.
 
Can you do external insulation?
 
Is it to be heated 24/7?
 
If you insulate then you have to meet building regs
 
To only do the bear minimum or less is short sighted and uneconomic on any reasonable timescale.

Marie
 
If you can organise the ground works yourself then a 7kW GSHP, including an integral hot water cylinder to save space, should cost between £8-9,000 + VAT.
 
the price should include supply and installation of the heat pump, all collector pipes and fluid, pressure testing of the coils and connection of the heat pump to your heating system.
 
AND there is still a grant available of £1,500 until the end of 2010 despite the withdrawal of the same under the LCBP.
 
It is essential when deciding on a system to make sure you get the radiators sized correctly. Triple rather than double rads might be needed where a heat pump is used.
 
Alternatively there is a high temperature heat pump system, but sadly no grant, where standard rads can be used. It costs a little more, but there would be no groundworks required.

My neighbour had a ground source, deep well, 125 meters type installed in his 150sq meter open plan villa. As he already had water rads, using a oil/wood fired furnace, there was only the job of removing the exixting furnace etc and oil tank. The new hole was drilled the first day, something like 8" diam, the 1st 6 meters were soil gravel etc so a steel pipe was installed down to granite rock. The 2nd day piping into the hole and to the house, including the exchange unit, and all was done by the evening, installed and up running, tons of hot water around 72C, and heating for the house despite outside temps of -25 this last winter. The total cost including everything and removal of existing rubbish, old tank etc etc etc....was £7652 + VAT. Of this sum, the labour charges were reduced by 50%, a government scheme, so the total cost was £6200 + VAT

Marie - you mention "We want to get ground-source heating" Yes! it is a good solution, but only if you already have an extremely well insulated house. With a heat-pump's limited max temperature (45 - 65 degrees) this will only be efficient with UFH if the insulation warrants it. So, I'd recommend - tackle the insulation first, then choose the most efficient heating system.
I know of one site where UFH is being fed with water at 70 C, by a boiler running flat out - and the heat is just leaking away. Another with a well insulated house have their heat pump output down to 35 C - and the house is cosy when -10 C outside. These sites are in the same area. Hope this helps to make the point.

The groundwork is simple, so not expensive. the cottage is small so suitable for it.
 
The worst thing about ground source is companies charging a fortune as if it's some sort of mystery. it isnt.... it's bloomin pipes in the ground, connected to a box in the untility room that makes the place warm.
 
there are some brilliant units on the market that dont get the exposure of the larger german names.......; message me if you want.

Marie, we put ground source heating into our new build two years ago, after having done our homework - we thought. It works beautifully but it is HORRIBLY expensive to run due to ever increasing electricity charges / we have a solar panel tied into the system and the house is very well insulated - spacious with underfloor heating and 4 bedrooms which are always UNheated-. If you are uber environmentally committed go ahead (the environmental bit though has to be questionable) but if you, like the majority of us, want to live without terrifying electricity bills go another route.Incredibly the media cites success stories related to cheap ground source heating but if you continue to investigate you will find it is most certainly a very expensive route to go down even though your house size may be a positive. Best wishes Mairi

Please, all HP users, enter your HP/consumption and construction data here:
 
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