In fact this is the general difference between us, when I don't know something I will ask. If I know something about the subject I will recount my experience. Please explain why it is not a viable concept.
Practical economical Idea for reducing heating bills.
- Thread starter PhilipClarke
- Start date
In fact this is the general difference between us, when I don't know something I will ask. If I know something about the subject I will recount my experience. Please explain why it is not a viable concept.
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This thread and the ideas contained within are a total joke.
Yes, in summer a loft space gets extremely hot. The very time when you won't want that heat circulating around your house.
In the winter, loft spaces are cold. Very cold, hence frozen and burst pipes for those houses which have outdated water systems. You certainly wouldn't want freezing air circulating into your house in winter.
A cheap 20w extractor fan is pretty much useless with ducting over 2 or 3 metres. With 45 metres, the air resistance will be far too high to get any airflow.
Loft temperatures recorded over the last 3 months are of no relevance, unless you are the sort of person who uses their central heating 365 days a year. Personally, I turned mine off in March, and haven't used it since - no need to.
A room to dry clothes in, which then has a fan or some other ventilation? Not only a waste of a perfectly good room, but just asking for mould and damp, which will inevitably find it's way into the rest of your house. Solution - hang washing outside to dry. Cost of solution = zero.
Preheating water in a tank in the roof - total bust. As others have already pointed out, this is not permitted, mainly because doing so will cause bacteria to grow in the tank, legionella being the most probable. This will kill people.
Apart from that, no one with any sense would have tanks or plumbing pipes in the roof. Such systems are outdated, and far better alternatives have been available for years.
For most people, the biggest savings on heating and other energy costs can be had with just 2 things.
1. Insulate the house properly.
2. Adjust their lifestyle to use far less energy.
Yes, in summer a loft space gets extremely hot. The very time when you won't want that heat circulating around your house.
In the winter, loft spaces are cold. Very cold, hence frozen and burst pipes for those houses which have outdated water systems. You certainly wouldn't want freezing air circulating into your house in winter.
A cheap 20w extractor fan is pretty much useless with ducting over 2 or 3 metres. With 45 metres, the air resistance will be far too high to get any airflow.
Loft temperatures recorded over the last 3 months are of no relevance, unless you are the sort of person who uses their central heating 365 days a year. Personally, I turned mine off in March, and haven't used it since - no need to.
A room to dry clothes in, which then has a fan or some other ventilation? Not only a waste of a perfectly good room, but just asking for mould and damp, which will inevitably find it's way into the rest of your house. Solution - hang washing outside to dry. Cost of solution = zero.
Preheating water in a tank in the roof - total bust. As others have already pointed out, this is not permitted, mainly because doing so will cause bacteria to grow in the tank, legionella being the most probable. This will kill people.
Apart from that, no one with any sense would have tanks or plumbing pipes in the roof. Such systems are outdated, and far better alternatives have been available for years.
For most people, the biggest savings on heating and other energy costs can be had with just 2 things.
1. Insulate the house properly.
2. Adjust their lifestyle to use far less energy.
So you agree then that for 50% of the year the loft is hotter than the house and therefore can be used to heat up the air. The "it's not posssible" argument has been disproved by Nuire in one of the preceeding pages.
No-one suggested freezing the attic space in winter at any point.
I thought that the air resistance would be a problem too, but it's not, the manrose specs suggested that it would be, but presumably they require that the fan maintain a certain pressure on the outlet, hot air being less dense probably helps too.
I don't personally subscribe to the idea of using a room for air con and already mentioned the problems.
Water is allowed to be preheated in low pressure heat exchange systems already so that point is moot, pretty much everyone knows about legionnaire's disease, what you are saying is that the heating of water would not be allowed in an open tank system which was never suggested.
So that would be every point countered and no one's laughing.
No-one suggested freezing the attic space in winter at any point.
I thought that the air resistance would be a problem too, but it's not, the manrose specs suggested that it would be, but presumably they require that the fan maintain a certain pressure on the outlet, hot air being less dense probably helps too.
I don't personally subscribe to the idea of using a room for air con and already mentioned the problems.
Water is allowed to be preheated in low pressure heat exchange systems already so that point is moot, pretty much everyone knows about legionnaire's disease, what you are saying is that the heating of water would not be allowed in an open tank system which was never suggested.
So that would be every point countered and no one's laughing.
Surely this endorsement of your idea by our Mick should be sowing the first seeds of doubt re. the whole concept!
Quick, get in there before Alan Sugar does. Could be the start of something.
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Yes - but the air in the loft will be hot in the summer, when no one needs the air heating.
The Nuaire product has a duct which is less than 1m in length, and the primary purpose of it is to provide ventilation, not heating. While the manufacturers claim it can be used to move heat from the loft into the room below and therefore reduce the cost of heating the building, there is nothing on that website to suggest any external verification of their claims or any kind of properly controlled testing.
They do however supply a 500W electric heater to go with their ventilation device, which amazingly has no electrical interlock with the fan unit, only a warning in the instructions to 'ensure the fan is running before operating the heater'.
Neither did I - the fact is that in the winter, the air in a loft will be at or below freezing for a lot of the time. Therefore useless, since the air will be substantially colder than the rest of the property.
If you honestly believe that the airflow created by a sub £10 extractor fan connected to 45m of flexible duct will even be noticable, then you are deluding yourself. There is also the significant issue that a cheap fan designed for occasional use for short periods will very quickly fail if left switched on for hours at a time.
What is more likely is that any airflow detected at the end of the duct was simply due to a difference in air pressure between the loft and the rest of the house. Not caused by the fan, but caused by a slight breeze outside.
All of which are carefully designed & approved and are used in such a way to minimise bacteria growth. They also cost far more than your 'instant and cheap' option.
In that case, what is this?
D
Deleted member 105431
As is often the case phil, academics often have no idea of real world practice/common sense and come up with stupid ideas.
Heat recovery systems (not ashp or gshp which you get confused with) are already a much better solution.
Heat recovery systems (not ashp or gshp which you get confused with) are already a much better solution.
Yes and that section was for using the retrofit as a heat sink so that the hotter water would continue providing hotter air through the night, it was not mentioned at all that an enclosed mains flow would go through it, I remember dead pigeons in the loft tanks when I was growing up.
I get it, you don't think it's a practical idea, hopefully you'll be proved wrong, and if not in two years then I'll do it after I've finished the next business and sold it on. You are wrong about the airflow through the ducting there was a temperature differential measured and I bought 45 m as that length came from screwfix, it wasn't all used and there are a lot more direct routes through.
Which is why I left academia 17 years ago, although the academics Sergey Brin and Larry Page whose paper on algorithms which produced google would probably disagree with you. I don't like American culture in general but they excel at using their academics to produce practical ideas, DuPont - Carbon Fibre, Richard Feynman and the theory of Quantum Electro Dynamics which produced semi conductor technology; molecular excitation of atoms to higher energy states and then cascade energy drops producing the Laser.
Whereas in the UK we don't even try to make things work as this thread proves. Seriously, you and flameport if you didn't believe that 20 watts was sufficient could have placed more than one fan in the ducting and done a cost analysis compared to solar power, you could work out from a home radiator how long the boiler is required to be on to increase room temperature by 1 degree Celsius compared to how the energy required to move preheated air, while range of things could be done rather just rubbishing the theory, so good luck with your endeavours, and good luck to the dreamers who seem to think that starting/ running a business means giving away a larger portion to already wealthy people, which is another UK mentality I fail to grasp.
Knowing that hot air is less dense and is trying to rise would add to the problem of trying to push it downstairs, no?
T
thatbloke
Also blowing hot air into a cool room would cool the hot air rather than heat the cool air would it not?
I hope it works out for you Philip , the new build market might benefit from something like this and glass roofs might be an idea but I dont think I'd like ducting running all over my old place.
I hope it works out for you Philip , the new build market might benefit from something like this and glass roofs might be an idea but I dont think I'd like ducting running all over my old place.
There is no need to do any of that. The basic idea is wrong.
In the winter, when heat is required, the air in the loft will be freezing cold.
In the summer when the air in the loft is hot, you don't need the heat.
Using heated water to heat the air is far, far worse.
right just read your post
1 as pointed out winter when you need heat the attic is cold
2 preheat system already exsit ic called solar and works all year round
3 running fan electrical money saved on heating via gas will not be
made up as electricty is more costly than gas(gas power station)
4 other methords of conserving heat are better such as loft insulation
or new type double glassing and their know at type of render which
can be retro fitted to old housing stock
5 finally their one thing you missed we use to air to heat people house it
now considerd old hat as it was not very good
sorry but you idea as mentioned sucks and blows
1 as pointed out winter when you need heat the attic is cold
2 preheat system already exsit ic called solar and works all year round
3 running fan electrical money saved on heating via gas will not be
made up as electricty is more costly than gas(gas power station)
4 other methords of conserving heat are better such as loft insulation
or new type double glassing and their know at type of render which
can be retro fitted to old housing stock
5 finally their one thing you missed we use to air to heat people house it
now considerd old hat as it was not very good
sorry but you idea as mentioned sucks and blows
simply untrue
you have a fantastic idea but with many flaws
basically you are talking about a system that will only give a return for a few weeks a year when the conditions are exactly correct
without sophisticated control you can easily have a negative value because your gains depend so much on the output off the sun and the wind direction and rain all very unpredictable as we know
This is the last post before I unsubscribe from this thread as I have another business to run.
No what we need is an idea to reduce bills economically that doesn't cost £20k and takes 20 years to make the money back which you need a subsidy for.
These tell you how your bills are going up by the subsidies paid for people installing solar power.
http://www.theregister.co.uk/2010/06/17/spain_sustainability_scam/
http://www.theregister.co.uk/2011/06/08/green_stealth_taxes_driving_up_leccy_price/
No the idea is to use it as a heat sink, as it it just sites there in the attic reheating the attic, there would be no contact with the air.
point 1, saving money for 50% of the year is still better than nowt and this is more economical than anything else on the table.
point 2. Apart from at night, when an old hot water tank heated during the day can release back the energy into the attic. Also doesn't work well in winter and see the articles and it's not econmically feasible.
point 3. you missed the bit about using a small solar power marine briefcase to power the fan
point 4. I am not against glazing or insulation, a responsible environmental house engineer would draft proof the house first. (Which reminds me that the diagram on the Naire website shows a very odd positioning of the putlet fan in the hallway way when hot air rises and relies on draughts a lot.
point 5. It was less efficient to use heated hot air than to use gas to heat water, but it didn't mean it didn't work, nor should one dismiss this concept and just throw all the hot air out of the attic when it's free (which is much more efficient.
The law of entropy states that hot always goes to cold, even when human perception appears otherwise. The situating of radiators under windows is the craziest of ideas when put forward that it mixes the cold air coming in, cold air never comes in unless there is a draught and a wind, it also does nothing to improve convection as the heat goes straight out of the window, there is no escaping thermodynamics.
I can assure you that there will be no ducting running all over the place in any build and already I checked and confirmed that even on grade II buildings installation would be possible. It's a pity that I am not ready for this business because locally 7,000 new homes are going up and the council has dictated conditions to the builders due to carbon footprint legislation, and even saving money/ energy for 50% of the year reduces the footprint and therefore increases the council's funding. An economical idea would work with that, insisting that every home cost an extra 20k with solar panels would be laughed out of the building. But of course people here don't believe it can work even though the experiments have, and next year I'll do a full installation in my home (Edwardian) that will not look out of place, but first I have to draught proof some areas and apply some Hungarian double glazing techniques to the original sash windows. It's already insulated past current building regulations and equals it's predicted banding on the certificate, what I want to do is beat that certificate and change the benchmarks.
In three months I have not found any point where the air in the attic was not hotter than the ambient air. In an insulated room (actually any room) the cold air source is going to be the ambient, whether it be through a draught or opening a door, so using the attic to increase the ambient at all times will save energy.
As mentioned before sophisticated need only be a plug in thermostat and an extension lean, but then a wireless boiler thermostat is available for £69 with timer, so in reality the production of such a unit is going to be about £5 (based on me getting things built in Taiwan for the bicycle business to import so it may not be accurate) once you remove the timer and programming and just set it to trigger when the temperature of the room is cooler than the attic.
Anyone that really wants to learn about the subject (like why turning off your mobile phone transformers at the mains is a waste) and see some pretty weird ideas (like using electric car batteries as storage for the national grid) should read the work of Professor MacKay here
http://www.withouthotair.com/
It's a book that you can buy but he also made it available to read for free online.
I'm turning off the notifications as I think I've explained enough and the naysayers have said their piece and I really must work on the new business, which will be tool hire and I would not be betting on HSS or Travis Perkins, even though I have only £1000 start up capital and no experience in the business. I'm not seeking investment either, I really do not understand this "you need a dragon" or "the apprentice" or "the idea must be brand new and original". My second business was selling plastic lens caps which isn't ground breaking territory either. I am surprised by the mentality here overall, I would have expected DIYers to be building businesses as well as things, Warren Buffet one of the world's richest men, only ever invested in construction, even small business and to get one share in his overall parent company (Berkshire Hathaway, which is actually officially a carpet textile business that owns all the others) will cost you $111400.
No what we need is an idea to reduce bills economically that doesn't cost £20k and takes 20 years to make the money back which you need a subsidy for.
These tell you how your bills are going up by the subsidies paid for people installing solar power.
http://www.theregister.co.uk/2010/06/17/spain_sustainability_scam/
http://www.theregister.co.uk/2011/06/08/green_stealth_taxes_driving_up_leccy_price/
No the idea is to use it as a heat sink, as it it just sites there in the attic reheating the attic, there would be no contact with the air.
adlplumbing said:
point 1, saving money for 50% of the year is still better than nowt and this is more economical than anything else on the table.
point 2. Apart from at night, when an old hot water tank heated during the day can release back the energy into the attic. Also doesn't work well in winter and see the articles and it's not econmically feasible.
point 3. you missed the bit about using a small solar power marine briefcase to power the fan
point 4. I am not against glazing or insulation, a responsible environmental house engineer would draft proof the house first. (Which reminds me that the diagram on the Naire website shows a very odd positioning of the putlet fan in the hallway way when hot air rises and relies on draughts a lot.
point 5. It was less efficient to use heated hot air than to use gas to heat water, but it didn't mean it didn't work, nor should one dismiss this concept and just throw all the hot air out of the attic when it's free (which is much more efficient.
thatbloke said:
The law of entropy states that hot always goes to cold, even when human perception appears otherwise. The situating of radiators under windows is the craziest of ideas when put forward that it mixes the cold air coming in, cold air never comes in unless there is a draught and a wind, it also does nothing to improve convection as the heat goes straight out of the window, there is no escaping thermodynamics.
I can assure you that there will be no ducting running all over the place in any build and already I checked and confirmed that even on grade II buildings installation would be possible. It's a pity that I am not ready for this business because locally 7,000 new homes are going up and the council has dictated conditions to the builders due to carbon footprint legislation, and even saving money/ energy for 50% of the year reduces the footprint and therefore increases the council's funding. An economical idea would work with that, insisting that every home cost an extra 20k with solar panels would be laughed out of the building. But of course people here don't believe it can work even though the experiments have, and next year I'll do a full installation in my home (Edwardian) that will not look out of place, but first I have to draught proof some areas and apply some Hungarian double glazing techniques to the original sash windows. It's already insulated past current building regulations and equals it's predicted banding on the certificate, what I want to do is beat that certificate and change the benchmarks.
big-all said:
In three months I have not found any point where the air in the attic was not hotter than the ambient air. In an insulated room (actually any room) the cold air source is going to be the ambient, whether it be through a draught or opening a door, so using the attic to increase the ambient at all times will save energy.
As mentioned before sophisticated need only be a plug in thermostat and an extension lean, but then a wireless boiler thermostat is available for £69 with timer, so in reality the production of such a unit is going to be about £5 (based on me getting things built in Taiwan for the bicycle business to import so it may not be accurate) once you remove the timer and programming and just set it to trigger when the temperature of the room is cooler than the attic.
Anyone that really wants to learn about the subject (like why turning off your mobile phone transformers at the mains is a waste) and see some pretty weird ideas (like using electric car batteries as storage for the national grid) should read the work of Professor MacKay here
http://www.withouthotair.com/
It's a book that you can buy but he also made it available to read for free online.
I'm turning off the notifications as I think I've explained enough and the naysayers have said their piece and I really must work on the new business, which will be tool hire and I would not be betting on HSS or Travis Perkins, even though I have only £1000 start up capital and no experience in the business. I'm not seeking investment either, I really do not understand this "you need a dragon" or "the apprentice" or "the idea must be brand new and original". My second business was selling plastic lens caps which isn't ground breaking territory either. I am surprised by the mentality here overall, I would have expected DIYers to be building businesses as well as things, Warren Buffet one of the world's richest men, only ever invested in construction, even small business and to get one share in his overall parent company (Berkshire Hathaway, which is actually officially a carpet textile business that owns all the others) will cost you $111400.
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