More mass I assume and they are designed to operate at 600C apparently.
A storage heater basically.
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A storage heater basically.
Weellll, the higher the temperature the more leakage you will have?
Hmmm, perhaps were I building a new house I might put a big sump in the middle, insulate it well and put a sand tank in there... certainly solves the problem of my solar panels controller switching off due to the tank temperature stat. How big would it need to be to store into the winter for a domestic house? Anyone done the maths?
Do you live above a mine shaft? Huge I should imagine
gaz1
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its not down to leakage its down to how much heat you would loose per day
hot water cylinders and solar cylinders loose a percentage over a day so when at higher temps its going to be days/months before your below the boiling temps of water depending on usage of coarse
whilst on the other hand you can also extra charge it by using the electric side of solar to top it up during the winter months
as long as you have a decent sized garden the sand solar unit is possible even if you was going to part submerge it there is other tech that can provide adequate insulation
chimney fire cement foam similar to firebrick up your chimney and other insulation properties in other materials its choosing the best that will last for 50 years +
even ground bore holing wont reach the temps of the sand battery or even the heated coils in the ground
we cant have a bore hole as there is mines in the area so alternatives must be used instead as we have the garden
Yes, heat leakage....
What solar diring the winter months? Like 10% of normal summer output?
So where's the maths? How big etc?
gaz1
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ive already provided you with a direct link to the info its not a model its already in use
as goes for the size of it ive also shown it
it also explains its usage and its charge cycles
as goes for what it supplies read up on it as its a small complex city it supplies with a good amount of buildings and a swimming pool and thats just on a read up
after that you could go searching on the test location and review some more
but like ive said ive taken a good look into this tech due to its high heat absorbsion and its storage time of months water cannot store heat as needs top ups often solar oil has a higher ratio of heat absorbsion so you can heat store that oil at a higher temperature itself
now i know water storage heat loss time
Most hot water cylinder manufacturers suggest that the water will lose between 1 kWh and 2.5 kWh of heat per day.
53c ( 127.4f )the temp drop per day is 8 degrees 45c you can make it less with more insulation
just so you know
i know rocket stoves can output 1000f in a simple format build but can reach over 2000f+ downdraft stoves also reach 2000f
as goes for the size of it ive also shown it
it also explains its usage and its charge cycles
as goes for what it supplies read up on it as its a small complex city it supplies with a good amount of buildings and a swimming pool and thats just on a read up
after that you could go searching on the test location and review some more
but like ive said ive taken a good look into this tech due to its high heat absorbsion and its storage time of months water cannot store heat as needs top ups often solar oil has a higher ratio of heat absorbsion so you can heat store that oil at a higher temperature itself
now i know water storage heat loss time
Most hot water cylinder manufacturers suggest that the water will lose between 1 kWh and 2.5 kWh of heat per day.
53c ( 127.4f )the temp drop per day is 8 degrees 45c you can make it less with more insulation
just so you know
i know rocket stoves can output 1000f in a simple format build but can reach over 2000f+ downdraft stoves also reach 2000f
Back to hear pumps for a second, since it sounds like there are some from the industry commenting. Round here they're promoting air source. Are there any figures for how well these perform when heating is most needed, in cold weather? For example last December outside air temperature went down to -16 Deg C. One day the higher temperature was -7. In other years we've had a February where it didn't go above zero for a whole month.
Without really knowing, I doubt that you're going to get a COP of 4 when the source air is at that sort of temperature.
Without really knowing, I doubt that you're going to get a COP of 4 when the source air is at that sort of temperature.
brewdexta
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In theory you can extract energy form something all the way down to absolute zero at -273c but I guess the COP may not be so good 
I believe heat pumps are basicaly just refrigeration units in reverse, if so this suggests they will work down to -22c same as your freezer does. However if they used different freons and other design changes, maybe lower than that. I guess it is diminishing returns.
All I know is that my brothers farm and holiday lets uses both ground and air source heat pumps and they are pleased with them and they live on the North York moors which can be a wee bit nippy at times
They moved out of the farmhouse recently, their daughter moved in with hubby and kids. They moved into a recent conversion of a newer farm building on their farm, so probably high levels of insulation and it uses UFH.
The air sound heat pump on this buildings keeps it well toasty, my SiL likes it warm. So much so that it split a wooden coffee table I made them. Another repair I need to get around too...
So the key is probably lots of insulation and a properly designed system.
I believe heat pumps are basicaly just refrigeration units in reverse, if so this suggests they will work down to -22c same as your freezer does. However if they used different freons and other design changes, maybe lower than that. I guess it is diminishing returns.
All I know is that my brothers farm and holiday lets uses both ground and air source heat pumps and they are pleased with them and they live on the North York moors which can be a wee bit nippy at times
They moved out of the farmhouse recently, their daughter moved in with hubby and kids. They moved into a recent conversion of a newer farm building on their farm, so probably high levels of insulation and it uses UFH.
The air sound heat pump on this buildings keeps it well toasty, my SiL likes it warm. So much so that it split a wooden coffee table I made them. Another repair I need to get around too...
So the key is probably lots of insulation and a properly designed system.
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Everyone needs to remember gas and oil are approx 1/4 the price of electricity so even if the heatpump really is 4x more efficient the running costs will just about match.
In many countries the cost of electricity is around the same as oil and gas hence heatpumps make more sense.
In many countries the cost of electricity is around the same as oil and gas hence heatpumps make more sense.
Blobber
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And thats the problem, very few houses in the UK are properly insulated and cant be properly insulated due to the construction, as for properly designed systems I doubt there are many installers that meet that criteria...
gaz1
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im going to say something that everyone should always remember
whilst many new builds dont have chimneys many chimneys have been taken out in old builds but they had there uses you find many are like flats all they have is electric
sealed insulated homes are the key to many new systems but they all have a major problem electricity
whilst those houses with chimneys can light a fire and get warm weather gas or by a wood stove the electricity houses cant so many people will be sat there huddled trying to keep warm
its no fun in 6hrs try 24hrs or even 48 or at worst a full week of no electricity supply then your suffering
try heating your food as its the same thing at least if you have a gas supply you can light the gas stove
whilst many new builds dont have chimneys many chimneys have been taken out in old builds but they had there uses you find many are like flats all they have is electric
sealed insulated homes are the key to many new systems but they all have a major problem electricity
whilst those houses with chimneys can light a fire and get warm weather gas or by a wood stove the electricity houses cant so many people will be sat there huddled trying to keep warm
its no fun in 6hrs try 24hrs or even 48 or at worst a full week of no electricity supply then your suffering
try heating your food as its the same thing at least if you have a gas supply you can light the gas stove
"We're all doomed, dooomed"
I jest of course, but you have a point - winter blizzards bring down overhead supplies (where I live), no wood burner, no leccy, you will be stuffed. I have one of those terribly inefficient woodburners...
And, to return to the OP, it continues, another old stone house getting ripped apart to fit PV - I wonder if they're getting a ASHP? Maybe not - its a solid wall house.
We went for 4 or 5 days with no electricity last winter. Luckily with the oil fired aga and woodburner we were fine.
gaz1
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however your oil fired aga wouldnt work as its electric fed so would be useless
so that would mean your left with the woodburner and need a generator to supply the oil fired aga
ive built myself a small rocket stove cooker just for this point at least i can cook on it as dosnt need electric to run it
julianthegypsy
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The same idiot that wouldn't give me a manual for our heat pump explained that we couldn't open up the fireplace because "we can't keep burning fossil fuels ", despite the fact that I make woodburners for a living and wood is clearly renewable, and when I asked what we should do in the event of a (frequent) power cut, said I should get a generator. I despair.
Probably the same idiot telling me I was daft not to rip my oil, water tank and PV out to fit his gshp...
Obviously these people are getting customers tho..
Morrisman
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And the 6 million tons of wood we import from the American every year, that should come under incineration too. They call it 'green' because it is 'renewable' but it is still burned.....
He said the Aga worked fine with the power cut though.... I imagine the oil is gravity fed - its hardly a complex setup. I dont know about Aga but many of the Rayburns were a wick based system -
My oil fired AGA works fine!
There is a slight drawback in that the thermostat is electrically controlled. If power fails it defaults to low. There is a manual over ride to switch it to high instead which is what I did.
The older mechanical ones were better.
Yes it has a wick
