Something for Nothing?

Strangways

Strangways

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Yes
Well not exactly...

1kW of electricity consumed can give you up to 6kW of heat, so you are effectively getting 5kW for nothing. That's what the latest range of heat pumps can produce. In addition the government has reduced VAT on domestic heat pumps to only 5%, but how many people are aware of it?

We keep hearing how we should be green and cut energy costs and how we should use renewable energy, but how many people are actually aware of these systems?

I really would be interested to know if any of you are familiar with the 'Heat Pump' as an alternatve and extremely efficient energy source, because I just don't feel the government or energy suppliers are doing enough to increase awareness.

Your coments would be apprecated.
 
Never heard of it.

You might want to think about making this a poll - so you get both the yes and no answers?
 
I've never set up a poll, I wouldn't know where to start.

In simple terms a heat pump transfers heat from outside to inside as opposed to generating heat. The most common type is a reversable air conditioning unit that cools in the summer and heats in the winter. This is known as an air to air heat pump.
You can also have an air to water heat pump that transfers the heat from the outside air to an underfloor or radiator water system.
Ground source heat pumps are now becoming more common where the heat is taken from underground rather than outside air.
 
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Well all you do is install a heat pump unit aprox the size of a fridge freezer, dig a few trenches around your property to accommodate the pipework,if you can borrow some of the neighbours land all the better. You might want to fit larger than normal radiators as ordinary ones are no good for this system, and oh yeh to really benefit from it make sure your house is fully insulated, any cavity walls as well :D Did I mention about installing an immersion heater tank for topping up the temperature for the hot water :thinking:

Bargain I say, probably get any savings you make back in next to no time :lol:
 
u8myufo said:
Well all you do is install a heat pump unit aprox the size of a fridge freezer, dig a few trenches around your property to accommodate the pipework,if you can borrow some of the neighbours land all the better. You might want to fit larger than normal radiators as ordinary ones are no good for this system, and oh yeh to really benefit from it make sure your house is fully insulated, any cavity walls as well :D Did I mention about installing an immersion heater tank for topping up the temperature for the hot water :thinking:

Bargain I say, probably get any savings you make back in next to no time :lol:
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You have obviously looked into ground source heat pumps, and I agree that these are not best suited to domestic retrofits. However there are a lot of these starting to go into new builds as it is easy to install the pipework when the foundations are being built and the radiators can be sized to suit.
However the new air source heat pumps produce high enough water temperatures to suit existing radiator and hot water services. They are designed to replace existing boilers.

To benifit from any heating system you should insulate your house and even more so if you are paying full price for heat in the first place.
 
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Funky, so they use the 1k of lecky to pull heat from the ground and pipe it into the building like a backwards fridge.

I'm intruiged by this as we live in the sticks with a fair bit of land so it could work quite well, off to google the grants now
 
Of course we know little about this kind of thing, after all, won't that cause the government and all them energy companies to lose out on VAT and profits.

<---- Cynical mode off.
 
I can understand your cynicism Ian, but from my dealings with the government and the Carbon Trust on these issues it appears more likely to be a mixture of ignorance, incompetence and lack of communication.

Technology in efficient heat pumps that use renewable energy is moving very quickly and without doubt it will become far more widely used as more as more people become aware of the benifits.
 
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Yep Ground source heat pumps, basically its a fridge in reverse :bonk: very simple yet bloody brilliant
 
Yep, GSHP or Air source HP are great for new build, less convincing for retrofit, but can still be good, our local council has been retrofitting into its oap houses and says that they are very pleased withthe results. They are using flat panels in the earth rather than pipes to get round the space issue - be interesting to see how well the panels last. Best with a heat store and underfloor heating or high efficiency rads because the efficiency drops right off if you want high temps, so you prob still need some sort of top up heat source.

Good luck getting a COP of 6 - ask the supplier about the test conditions for that figure, between 3 and 4 is more like.

You also need to think about overall costs compared to eg high efficiency gas boilers. The grants are a bit of a waste of time on most green stuff - the suppliers pay so much to get on the scheme that they end up charging a fortune for the kit - if you are prepard to sort i t yourself then you can see some decent pricing - navitron etc.
 
who? said:
Yep, GSHP or Air source HP are great for new build, less convincing for retrofit, but can still be good, our local council has been retrofitting into its oap houses and says that they are very pleased withthe results. They are using flat panels in the earth rather than pipes to get round the space issue - be interesting to see how well the panels last. Best with a heat store and underfloor heating or high efficiency rads because the efficiency drops right off if you want high temps, so you prob still need some sort of top up heat source.

Good luck getting a COP of 6 - ask the supplier about the test conditions for that figure, between 3 and 4 is more like.

You also need to think about overall costs compared to eg high efficiency gas boilers. The grants are a bit of a waste of time on most green stuff - the suppliers pay so much to get on the scheme that they end up charging a fortune for the kit - if you are prepard to sort i t yourself then you can see some decent pricing - navitron etc.
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The COP of 6 is a Hitachi S series wall mounted air to air heat pump so it will be more efficient than an air to water. It's based on standard NEEMA conditions of 7 deg C outdoor temp and 20 deg C indoor.


The air to water heat pumps that they produce have a COP of 4 and can now produce water temperatures of 65 deg C. Their new units just take the place of an existing boiler.
 
We looked into getting a heat pump last year as they are both cost and energy efficient. I now live in Canada, which is maybe why I know what you're talking about, as they are quite popular here. It's basically a big box that is fitted to the outside of the house, and acts as a heater in winter and provides aircon in summer. We have duct vents for heating, fuelled by a gas furnace at present. Hopefully will splash out on one this year. They are about $6000, but there is a Government incentive here too.
 
minimeeze said:
We looked into getting a heat pump last year as they are both cost and energy efficient. I now live in Canada, which is maybe why I know what you're talking about, as they are quite popular here. It's basically a big box that is fitted to the outside of the house, and acts as a heater in winter and provides aircon in summer. We have duct vents for heating, fuelled by a gas furnace at present. Hopefully will splash out on one this year. They are about $6000, but there is a Government incentive here too.
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Are they all Japanese heat pumps in Canada?
 
I've been aware of them for years but not done anything as I've always intended to move home. I would consider it after moving though.

Strangways said:
The air to water heat pumps that they produce have a COP of 4 and can now produce water temperatures of 65 deg C. Their new units just take the place of an existing boiler.
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So, how much for purchase and install of one of those to replace a 90,000 BTU boiler? And what would it cost to run?

A new oil boiler in that range would cost me around £900 purchase, plus install and around £400/year to heat my home and provide hot water (one tank of 1000 litres / year for a 4-bed bungalow, obviously varies depending on the price of crude and the USD exchange rate)
 
Personally dealing with some of the systems at work there great for new builds but no the best thing for existing installlations, unless you want airconditioning then the reversable air ones are great.

But the cost of ground heat pumps for some domestic plots for me is pretty much a no go, but are a very good idea when building new blocks of flats, which with the current building regs the way they are is becoming very commonplace to see these units going in.
 
Strangways said:
The COP of 6 is a Hitachi S series wall mounted air to air heat pump so it will be more efficient than an air to water. It's based on standard NEEMA conditions of 7 deg C outdoor temp and 20 deg C indoor.


The air to water heat pumps that they produce have a COP of 4 and can now produce water temperatures of 65 deg C. Their new units just take the place of an existing boiler.
Click to expand...

Thats a substantial improvement on things since I looked then. Is that COP4 when producing 65c?

I was dubious of air/air because I'd heard poor reports about things when temps get low. What about performance at say -5 external/15 internal?
 
When you manage to get the truth out of any of the manufacturers of ground source or air source heat pumps they will admit that the payback period of a heat pump will be longer than the lifespan unless you are away from mains gas.

Rather than spend money on heat pump technology you are better off improving the insulation on your property and upgrading the controls on your heating system.

Heat pumps will only become viable where natural gas is available if the level of grant available is massively increased.
 
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