Those upfront costs

£12000-£15000 to have the garden dug up, buy the heat pump and install underfloor pipes - the lower water temperatures produced by GSHP are best suited to underfloor heating.

So those government grants would need to be pretty substantial to beat the typical £3000-4000 cost of installing gas central heating. Start talking about a Combined Heat and Power gas boiler and you have a more achievable solution.

GSHP is currently best suited to new installations or replacing oil-fired boilers which are not in reach of the gas grid.

Pretty good

It is. We've had ours over here in Sweden for many years now, but the £10000 to bore the well and install the pump and heat-exchanger hurt. If i hadn't plumbed in the radiators myself it would have hurt a lot more. On the other hand, the value of the house went up and it's -12C outside, but the house is toasty!

The reg should have picked up the need for a cluebat here

A few problems with the report.

1. This type of installation requires drilling to a depth which in the UK is strictly regulated and requires a permit from the UK geological survey. So you have to fight for 6 months+ for a permit (and based on the trouble it takes to get a water well permit you are not likely to get it). After that you have to buy a unit abroad, find an installer (which in the UK again may require special permit, etc), etc.

2. The really cheap types of installation where you drill two boreholes put a stick of dynamite down on the bottom to crack the rock a bit and run water down, water up are unsuitable for the UK. Most of UK is unfortunately limestone or even worse - chalk. Compared to the UK Scandinavia sits on top of a nice granite shelf. There, the water pumped down is not going anywhere but coming up the neighbouring "up" borehole. In the UK the same water will dig a nice cavern where your house will subside or run off instead fo coming up via the other borehole.

However, the UK is still suitable for other types of heat pumps which are used in places around the world which sit on limestone like the mountain part of South of France, US Mid-west, etc):

1. Air-exchange heat pumps. An air exchange heat pump unfortunately is pretty useless under 5C. In the 5-15C (which is most of the year in the UK) it can provide the same efficiency boost as a ground bore (up to 3 times) to electric driven central heating and water. Not perfect, but way better than using "naked leccy". Probably marginally more cost effective than gas even at current prices.

2. Spring water exchange heat pumps. Same principle as the ground bore, but you use water from a nearby stream or river. If regulated properly (after all, we do not want to freeze all of our rivers, do we?) it is a viable option for 50%+ of the UK. So the flooding menace which you hate running through your piece of suburbia can suddenly become a source of heat to all inhabitants.

Other methods

Groundsource also works with vertical boreholes so the area of land required is actually quite small, if loads of these type of systems were installed then the price of boring would probably fall to less than that of digging lots of trenches on the surface.

There are also airsource heat pumps which work almost exactly like air-conditioning units in reverse, removing heat from the air outside and putting it inside (as hot water). These work even with air temps below 0C but are obviously less efficient than GSHP but much cheaper and easier to install.

These are the kind of decent energy saving thing people should have been persuaded to install years ago - not pathetic wind/solar where 1kW is about as good as they get for residential installations. With GSHP you could put in 6kW of electric and get 18kW of heat out constantly. A 12kW wind turbine would be huge in comparison both physically and cost-wise.

geo-sourced heat pumps

I am considering a geo-sourced heat pump when my 9 year old standard unit finally dies. The downside is I need to decide if I want to put out the $5-7K extra cost over a standard air-sourced heat pump.

Here in Florida the electricity savings can be pretty substantial. But like everything it's a matter of working out the cost/benefit ration and pay back time on the initial investment. At least here in the states most homes have a large enough lot to have room for the required wells to install the piping loop in.

Heat pumps are awesome

I really like the idea of having a heater that is up to about 500% efficient. (You put in 1kW of electrical energy, and get out about 5kW of heat!) Interestingly, today's technology appear to include air source heat pumps so you don't need the (expensive) ground exchange loop.

There are grants available under the LCBP programme of, apparently, 900 UKP minimum for an air source heat pump and 1200 minimum for a ground loop (for homeowners). OTOH a random search on t'interweb indicates that a new ground source heat pump costs about 10k UKP, so it's still bloody expensive. An air source heat pump appears to be about 6k.

Some other points

* GSHP work because the temperature of the ground about 1.5-2m down is pretty constant all year round.

* GSHPs do need a three phase supply to drive the motor as they typically need to pump a huge volume of anti-freeze through the pipes in the ground.

* The CoP for GSHPs is usually quoted as 4 but more typically its probably about 2.5-3 when you take into account the level of quality of the installation.

* If you don't have the land you can dig down, typically a 100m straight down. A bit more expensive to drill down but cheaper than buying the land!

* An alternative to GSHPs is ASHP where the A stands for Air. Basically an air-conditioner that can work in both directions. Not as efficient as GSHPs but useful in the situations where GSHPs can be installed.

* Nice idea about attaching fridges and other heat dumping equipment (air-conditioners) to the system since you could dump excess heat into the ground in summer ready to pull it out in the winter.

In Sweden…

Most of the installations are what we call "bedrock heat", or something along those lines. Instead of running pipes horizontally near the surface, you make a single deep hole down to where it's hotter. Takes less space that way.

Illustrations and easy to read Swedish info over at http://www.energimyndigheten.se/sv/Lattlast/Hur-ska-du-varma-upp-ditt-hus/Varmepump/

Ceci n'est pas un titre.

This isn't new to me, but it's good to see the light of reason dawning in a government-influencing institution like this. Let's see how long it takes our politicians to completely mess it up.

It's a very good fit for the UK as most of our older housing stock is Victorian (terraced) houses with gardens. Said gardens can be easily dug up to fit the necessary bits of piping.

It's not much use in high-rise city centres, but there's an awful lot of parkland dotted around London which could be used to provide shared heating and cooling systems for these areas too.

Welcome to the 21st century

I can't remember a series of Grand Designs where the majority of the new builds *didn't* use ground source heat pumps. Has somebody somewhere finally noticed?

If I understand the technology right, you can if necessary also use the ground in the summer as a source of cold, ie cut the energy cost of air conditioning.

How's about an honourable mention for air-sourced heat pumps too? We've all seen them, in the "twin pack" air conditioners used in offices and server rooms etc. Now reverse the plumbing to bring heat *in* from outside. Some of them even take heat from the outside air and put it into water for the traditional central heating. OK the air temperature tends to be a bit more variable than the ground, but in most parts of the UK most of the time it's perfectly practical.

Air sourced heat pump technology may not be quite as exciting as the ground source stuff but it is at least applicable to buildings which are already built. There are a lot of those about. No one's going to rebuild specifically so they can get a ground source heat pump, some people *might* invest a few thousand pounds (on the domestic scale, for an existing building) for an air source setup.

Usual government timeline

I first read about this sort of thing in the late 1960s, and I think pretty thoroughly understood the pros and cons.

So, it's taken our government 40 years to catch up.

Whoa, hang on here...

You rather breathlessy charge off from mentioning that GSHP is a good means for regulating home temperatures (which is true) into running freezers and ovens (which is not true). The problem is the Second Law of Thermodynamics; while there is a fairly small temperature difference between dwelling space and the heat source/sink underground, there is a much bigger difference between an oven or freezer and that same heat pipe. That means the efficiency of the system will drop off dramatically for these applications since the quality of the thermal energy is low compared to the magnitude of the temperature difference at the 'business end'.

Flames because, well, you know.

Geothermal?

Using the earth as a heat sink/source is all very well, but what about some serious heat: geothermal? Its not just for the Icelanders. Just a few kilometers beneath our feet, the fires of hell rage, just waiting for the LHC to... Oh wait, wrong rant.

As pointed out, the up-front costs are prohibitive, but governments and globocorps alike can easily finance such a project.

Heat/Cool

COP is fun - it's available energy after all!

The problem with GSHP...

Cost.

An acquaintance is building his own home from scratch, and was looking at various heating solutions, including GSHP.

Looked like it would cost over £10k to install, which he baulked at - and that was if he hired a digger and dug the trenches himself.

So then HM Govt, offer to cover 50% of the cost of *that*, rather than using stupid stamp duty 'holidays', and you might actually get somewhere.

Steven R

Home city?

I don't live in a city…

Basic parameters, please

A farmer who I know built himself a new house on his own land and installed a ground source heat pump system - but it cost a lot and needed quite a bit of land. So maybe we could do with some parameters so that I can work out if my 70ft x 20ft back garden is big enough and if my bank manager can afford it. Over Xmas I'm putting in that £1 a roll extra loft insulation that the govt is subsidising...

One catch

The ground is not an unlimited source of heat; one problem that GSHPs have had in the past is the ground around the extraction pipes freezing. Once that happens, efficiency drops dramatically. This is more of a problem in northern latitudes.

Once the freeze occurs, it takes a long time for the ground to thaw, forcing the use of conventional methods of heating, thereby reducing the savings and overall efficiency.

Incidentally, the current level of CO2 in the atmosphere is in the area of 0.0035%. The easiest ways to reduce it is to plant trees and tell environmental activists to shut up.

netgeek

Oh what a good idea!

yup - GSHP are a great idea. Until you start trying to find a suitable "govt approved contractor" whose price eats up any subsidy you might be given :(

Also, it's most suited to underfloor heating, as the water is best raised to about 30C rather than 70 for radiators. My own plans fell by the wayside when the cost (not including groundworks) when way over £7K.....and as for having the house converted to be suitable for underfloor - just the 30K!!

Great for a newbuild tho - and I'd recommend underfloor (water) heating, which is all that survived from the GSHP project in the new kitchen.

In the Garden

I was thinking of how my neighbours would react if I dug up my garden and buried stuff in it. Then I had a brilliant idea. I just need to put in an anonymous tip in that there are illegal immigrants in my rose bushes and some bunch of nosey parkers will come round and dig up the lot for me.

I get 2 bonuses then. Labour saved and a warm feeling that some part of our xenophobic system has been fooled into leaving the vulnerable alone for a while...

Energy efficiency

Remember that energy efficiency is just as important as your GSHP or other source of heating. It's not glamourous or headline grabbing, but If you can reduce the demand in the first place, then you can install a smaller system and save some cash...

Not that Green and Could be expensive

Unless you already have a deep underground network say the "Tube" or a deep mine for example, the green credentials wander slightly when cost of energy is cast against the cost to drive a Bore hole,deep enough...the cost of the geological survey with some guarantee that the return water just doesn't disappear sideways and a vain hope to get a reasonable return on the investment in ones own lifetime. It would help to ensure that you actually have a closer to the surface geologically active environment to start with, cue, pictures of arctic snows across fields of basalt. Its Economics My Boy Economics!!!!

About time

Every house owner I know here in Sweden has fitted a heat pump - cheap, plentiful hot water & heating, ultra reliable and a very quick ROI. It doesn't require much digging or space either.

Factories & offices in and around Stockholm use the same technology for cheap air conditioning. Also, power stations here use the waste heat from combustion to pump steam around the city through insulated pipes to provide heating to buildings. Incredibly efficient compared to dumping the heat though cooling towers. Plus they can store up to 48 hours worth of superheated steam in large tanks to cover ups and downs in heat production, sudden cold snaps etc.

It's old and proven technology and now would be a good time for Britain to invest in this kind of infrastructure and create some jobs at the same time.

Grand Designs

So some one watched a grand designs from a few years back.

Now let's hear more of this sort of thing...

... Forget all the pointless "Global Warming is Man Made", "No it isn't!", "Tis so!" arguments and let's just hear positive things that people can do to actually lower their energy consumption and save themselves money instead!

Lie, Dam lies & statistics

"Ground source heating is a rapidly growing technology that has the potential to produce at least 30 per cent of the country’s renewable heat needs"

I smell bullshit here.

1. Most new houses being built simply don't have the land required to stick one in, heck if it has a garden big enough to stick a barbie in, it's classed as a "executive" 5 bedroom house (3 bed in old money)

2. In highly populated areas, again you have issues. Tower blocks, houses that back directly onto public highways, shared ownership land, protected land etc etc....

Still ok for us that live in the sticks, but call me when I can get my money back in less than a few years, sounds selfish, but I'd rather pay £10k of the mortage and actually think about not having to worry if I can afford to go food shopping this week.

It isn't that expensive...

I have recently installed my own GSHP. It is hardwork but easy for a good DIYer.

Cost of mini digger hire, pipes, coolant, heat pump, underfloor heating pipework and manifold but not installation was £5.3k (£6.5k less £1.2k grant from government).

It runs of a single phase supply (not three phase) and heats a 4 bed house for around £300 to £350 per year and there are no maintenance costs if you can read a gauge once a year to check for leaks.

Yes you do need to install underfloor, it doesn't work well (efficiently) with radiators and yes you do need a very well insulated house to go with it.

We are very happy with out system and believe it was only about £1k more expensive than an oil fired system and will pay back within 2 years.

I have a GSHP...

... and it works really nicely. We had three 35m channels dug ~1.5m deep, a few metres apart and buried the coils in the back garden. These connect via a manifold to the heat pump itself in the utility room. That, in turn, is connected to the hot water system, and the underfloor heating system. We get all our space and water heating requirements fulfilled (5 bed semi) for around £100pcm - which compares well to the amount we were paying for LPG.

We could only do it because we already had the workmen in renovating the house, the back boiler had packed up and there's no gas in the village. It made sense to rip the old system out and get this installed.

Finding people who know how to size and plan for this kind of system is tricky, but I recommend the technology highly. It is an expensive retrofit and, as mentioned previously, there are many cheaper ways of saving money and making life more comfortable with insulation, draught-proofing, quality glazing, and attention to appliances.

Free consultation

Write a trivial story about a less than trivial subject and get 30 well informed comments for free. So, who at El Reg Towers has just bought a plot of land and is doing a new build? It's a tactic I use my self and don't mind seeing it here because I'm interested in the same stuff.

I thought Combined Heat and Power CHP was a useful thing to employ in the UK...

ASHP++

score another vote for air-sourced heat pumps here. You've also be well advised to hook in solar hot water, which is much cheaper and more efficient that PV, and produces useful supplementary heat even in gloomy Blighty.

one hitch with both schemes it that they both require you to fasten boxes to the outside of your house; the planning laws need to be amended so you can do it without the nimbys whining.

Pretty handy

I've recently seen these installed in a new build house and combined with a bit of consideration for the insulation and other related matters they work an absolute treat. Seeing how ice forms on the pump itself is quite something as well...

Very satisfied heat pump user.

We've had ours for four years and it is the best heating system we've ever had.

Land area is a consideration, but not as big as we had thought. The biggest part of the installation cost was digging the trenches for the collector coils - but this could be a DIY job, it's not sophisticated work.

You do need to attend to insulating the property, but that goes for any heating system.

An undefloor system is definitely an advantage, but modern heat pumps can run with hot side water temparatures of over 50 centigrade at good efficiency, so it's possible to use a combination of extra insulation and increased radiator size. Have a look at the manufacturers temparature differential vs efficiency curves.

Hot water is not a problem - ours delivers water at 50 centigrade plus, and will comfortably deliver enough of that to run a shower in "real time" - IE it can replace the hot water as fast as the shower uses it.

Add in the ability to use green electricity and the fact that the system is guaranteed for five years, has a rated life of 30 years and no servicing requirements (much better than boilers,because there's no nasty combustion, only a couple of rotary moving parts and all sealed).

You may need a three phase supply, but only for larger units. It's actually quite cheap to get that - somewhat to our surprise.

BTW, the comment about ground loops freezing is irrelevant - that's why they are filled with antifreeze!

Money saving my arse...

Difference between gas and gshp is £190 a year. So say it costs you the least amount for the installation. Assuming no repairs whatsoever, it'd take THIRTY FIVE YEARS to break even compared to running gas. If you're looking at the top end of the installation cost, you are looking at a SEVENTY YEAR period before breaking even. Obviously these are variable depending on the cost of gas. You're still going to need a gas boiler anyway to top up what it can't supply. And as the climate changes, are you actually even going to need it?

Yet another "money saving" idea pumped by the eco-mentalists which doesn't actually save money.