Snow is a good insulator, a bit like an oxymoron, it’s certainly counterintuitiveIf that was true then countrys with long snow cover would get almost no heat into the soil through the winter as the snow would reflect most of the sunlight
Snow is a good insulator, a bit like an oxymoron, it’s certainly counterintuitiveIf that was true then countrys with long snow cover would get almost no heat into the soil through the winter as the snow would reflect most of the sunlight
Have a look at any ground temperature graph relative to depth and seasons. You will see a significant rise in ground temperature of the first few metres during the months that have the higher solar radiation and air temperature. Even at depths of 5 metres you will see a temperature rise in the summer. It will lag the solar and air temperature inputs due to the huge mass of ground absorbing the energy so the peak will be a little later than at shallower depths but it is a definite peak.Think about going to the beech on a hot summer's day. Yes the sand will be hot on the surface but dig less than a foot down and sand quickly becomes cold. Soil is the same, dig down a foot or two and you'll find the temperature is much colder. This soil temperature a few feet down doesn't change much, in the height of summer or the middle of winter the temperature of the soil only a short distance from the surface remains largely the same temperature.
If the Sun warming the soil was how these system's worked then they would be terrible in the winter when you want them to work and brilliant at heating your house in the summer when you don't want them. Also these systems can work in reverse to cool your house in the summer, so you don't want to be trying to expel heat energy from the house into hot earth on warm summer's days.
These systems work like air-conditioning. They use a compressor to compress a liquid or gas, when you compress liquids and gasses they get hotter and increase in pressure. When you drop the pressure, you loose heat. So the compressor pushed the compressed hot fluid into the house. It then radiates the thermal energy into the house and looses pressure. The now cold fluid runs into the ground, heated buy ground temperature, to return to a normal temp, then the compressor warms it up again.
In a car air conditioning system the "house" would be the condenser under the bonnet, and the ground outside would be the evaporator in the cabin. condenser gets hot, cabin gets cold.
It doesn't matter how deep you go with the pipes because its the constant temperature you want. If the system was reliant in anyway from the heat of the sun then it wouldn't work at all on an over cast day or in the middle of the winter when the ground is frozen or covered in snow.
The pipes laid out across the garden is "easier" because you don't need a hole boring machine and ground survey to install the system, just bury the pipes a few feet down and be done with it. But it takes up far less space to just drill a vertical hole into the ground and fit all your pipes in a small patch of ground which is much better for modern houses with small gardens.
Looking at research papers the average 1m temperature for soil is 8.8'C in the north of Scotland and 12.7'c in the south of England.
Now answer this. If there is snow on the ground and puddles are literally frozen over with an air temperature of say -3'C then how can the sun be heating the earth below that to 12'C ?
This has nothing to do with Geothermal energy in terms of extreme depth and pressures leading to "geothermal energy" we're not dealing with Magma, but the earth is hot and it does not need the sun to stay hot. stick a temperature probe into the ground in a densely covered forest on a cold day and you'll still find a meter or two down that ~10'c temperature. In fact you have literally confirmed exactly my point in your post !!
So sorry but the sun has nothing to do with how a ground source heat pump works. Air source heat pumps as per the name suggests are much more susceptible to changes in the heat of the air caused by the heat of the sun and for that very reason, they are horribly inefficient and expensive to run.
Think driving around in your car with your windows open in the winter and running the aircon, that will give you some idea of how efficient an air source heat pump is.
The whole planet maintains its temperature, and there are studies of the ground under the Antarctic where the weather is in double digit minus figures and a couple of meters down its still a toasty 15°C where the sun isn’t shining for 6 months a year.Have a look at any ground temperature graph relative to depth and seasons. You will see a significant rise in ground temperature of the first few metres during the months that have the higher solar radiation and air temperature. Even at depths of 5 metres you will see a temperature rise in the summer. It will lag the solar and air temperature inputs due to the huge mass of ground absorbing the energy so the peak will be a little later than at shallower depths but it is a definite peak.
Think of the first 10 metres of ground as a giant heat sink that is constantly being fed from the sun, it heats up in summer and slowly releases that energy which can be taken by ground source heat systems in winter.
The whole planet maintains its temperature, and there are studies of the ground under the Antarctic where the weather is in double digit minus figures and a couple of meters down its still a toasty 15°C where the sun isn’t shining for 6 months a year.
Yes heat does come from the sun and it would be stupid to argue otherwise but there is also a lot of heat permeating up as well. A ground source heat pump does not need sun heated ground to work, it just needs the ground and pipes can be laid out across a large area or sunk horizontally into the ground without any effect on how the system functions
You seem to be missing the fact that the ground is acting as an accumulator for the solar energy.What your graph shows is that the deeper you go the less impact the seasons have on the ground temperature, almost like there might be heat coming from somewhere else ?
But weather you’re at ground level of 12 feet deep there is this average trend throughout the year of about 62F about 15-16C
In the Antarctic where the sun doesn’t shine for 6 months of the year and the air temperature is -40C and the ground is burried under feet of freezing cold snow, you dip a little below the surface and the temperature is 15C !
No ground source heat pumps do not rely on the sun to work, they rely on inherent heat that is in the ground that is not just from the sun but is there all the time no matter where you are in the world.
Even at the bottom of the deepest parts of the sea 30,000+ feet away from the surface and the sun, the temperature is still above freezing.
I will say it again heat pumps do not work by pumping the heat of the sun.
They will work even in the coldest parts of the world, they will work were the sun is unable to get to the ground, and as per the comment that started this conversation, they do not need the sun to “recharge” the heat of the ground in order to continue working.
You seem to be missing the fact that the ground is acting as an accumulator for the solar energy.What your graph shows is that the deeper you go the less impact the seasons have on the ground temperature, almost like there might be heat coming from somewhere else ?
But weather you’re at ground level of 12 feet deep there is this average trend throughout the year of about 62F about 15-16C
In the Antarctic where the sun doesn’t shine for 6 months of the year and the air temperature is -40C and the ground is burried under feet of freezing cold snow, you dip a little below the surface and the temperature is 15C !
No ground source heat pumps do not rely on the sun to work, they rely on inherent heat that is in the ground that is not just from the sun but is there all the time no matter where you are in the world.
Even at the bottom of the deepest parts of the sea 30,000+ feet away from the surface and the sun, the temperature is still above freezing.
I will say it again heat pumps do not work by pumping the heat of the sun.
They will work even in the coldest parts of the world, they will work were the sun is unable to get to the ground, and as per the comment that started this conversation, they do not need the sun to “recharge” the heat of the ground in order to continue working.
I’m not going to keep repeating myself so just to make this point one last time. your argument is floored ! again, In the antartic ground, where the sun doesn’t shine for 6 months of the year the air temperature is -40C and the ground is covered in a thick layer of snow and ice there is still a temperature constant a few feet down, when the temperature of the soil above it is at a constantly lower temperature.You seem to be missing the fact that the ground is acting as an accumulator for the solar energy.
Perhaps this will help. Note key words like solar energy
But if the soil heat was coming from the sun and needed to be replenished it would make the heat pump useless as the snow would stop any more heat getting into the soil as snow is great at reflecting solar rays being whiteSnow is a good insulator, a bit like an oxymoron, it’s certainly counterintuitive
Kensa supply both borehole and surface systems and their buried pipework mentioned would be the latter.I’m not going to keep repeating myself so just to make this point one last time. your argument is floored ! again, In the antartic ground, where the sun doesn’t shine for 6 months of the year the air temperature is -40C and the ground is covered in a thick layer of snow and ice there is still a temperature constant a few feet down, when the temperature of the soil above it is at a constantly lower temperature.
Again WITHOUT THE SUN THE GROUND STILL MAINTAINS A CONSTANT TEMPERATURE.
You found one website trying to flog these systems that supports your claim, but this does not account for the fact that they install these systems in vertical bore holes which at 100m deep are not subject to any variability in ground temperature.
This deeper temperature is ~10 - 15C and is constant the world over.
Yes the closer to the surface you are the ground is obviously going to be subject so some variability but when you actually want a heating system to work, the ground temperature effects of the sun are at their lowest. But it is not reliant on pumping the suns heat.
As highlight by many of the comments on here (I think maybe including your own) the temperature only goes up the deeper and further away from the sun you go.
Think of the top 10 metres of ground as a huge heat sink or accumulator which is warmed by the sun, mainly in the summer.But if the soil heat was coming from the sun and needed to be replenished it would make the heat pump useless as the snow would stop any more heat getting into the soil as snow is great at reflecting solar rays being white
Is the point I was making
So there for soil heat must be coming up from deeper below
I’ll keep referring you to my previous post.Kensa supply both borehole and surface systems and their buried pipework mentioned would be the latter.
Three more articles explaining where the energy comes from.
I believe you should be able to see the sources at the top.
There is a lot of heat coming from below, about 50% of the energy that heats the earth and atmosphere comes from the sun, the other 50% comes from the earth itself.There will be a small amount of heat coming from much deeper (which Andy refers to ) but if you look at my previous graph of seasonal ground temperatures relative to depth, you should be able to see that in the periods of high solar radiation / summer the temperature of this upper layer rises dramatically whereas if the heat was mainly coming from the earths core then it would be almost constant.
So, where does the energy come from? If you take the heat out of the soil, day after day around the pipes, then the soil will get colder and colder, the heat energy has to come back into the system from somewhere. I dont believe there is enough to say from below, as that would be effectively geothermal.Think about going to the beech on a hot summer's day. Yes the sand will be hot on the surface but dig less than a foot down and sand quickly becomes cold. Soil is the same, dig down a foot or two and you'll find the temperature is much colder. This soil temperature a few feet down doesn't change much, in the height of summer or the middle of winter the temperature of the soil only a short distance from the surface remains largely the same temperature.
If the Sun warming the soil was how these system's worked then they would be terrible in the winter when you want them to work and brilliant at heating your house in the summer when you don't want them. Also these systems can work in reverse to cool your house in the summer, so you don't want to be trying to expel heat energy from the house into hot earth on warm summer's days.
Yes, if designed that way. But many homes in the UK and 50 to 100 years old or more. Poorly insulated, and require ventillation to prevent dampnessWould you believe that a small house can be heated with a heat pump which only draws 0,8 - 1 kWh of energy? It also dries the indoor air, filters it and keeps it nice and warm. All other electric heaters can be shutdown. Each heater draws 0,6 kwh-1 kwh of energy already![]()
We literally live on a ball filled with liquid hot rock. So yes 50% of the heat energy we get here at the surface comes from the ground.So, where does the energy come from? If you take the heat out of the soil, day after day around the pipes, then the soil will get colder and colder, the heat energy has to come back into the system from somewhere. I dont believe there is enough to say from below, as that would be effectively geothermal.
These system as fitted near the surface, and that would imply that the energy comes from above. On a cold day then it can only be solar since the air temp may be very cold.
So again How does this explain the fact places with massive snow cover for long periods of the year still can use ground source heating? Snow can reflect 90% of solar radiation so how is the sun going to heat the soil back up?So, where does the energy come from? If you take the heat out of the soil, day after day around the pipes, then the soil will get colder and colder, the heat energy has to come back into the system from somewhere. I dont believe there is enough to say from below, as that would be effectively geothermal.
These system as fitted near the surface, and that would imply that the energy comes from above. On a cold day then it can only be solar since the air temp may be very cold.