John Doe 2 | 06/08/2023 11:47:53 |
![]() 441 forum posts 29 photos | Duncan; No, it isn't !! I think an 'h' went missing, i.e. 6kWh per day, (per bore-hole), but I cannot remember now where I saw that figure. Somewhere down an internet rabbit hole no doubt. To quote from Wikipedia: "Since a heat pump moves three to five times more heat energy than the electric energy it consumes, the total energy output is much greater than the electrical input. This results in net thermal efficiencies greater than 300% as compared to radiant electric heat being 100% efficient. Traditional combustion furnaces and electric heaters can never exceed 100% efficiency. Ground source heat pumps can reduce energy consumption – and corresponding air pollution emissions – up to 72% compared to electric resistance heating with standard air-conditioning equipment".[24] And: "Ground source heat pumps are recognized as one of the most efficient heating and cooling systems on the market. They are often the second-most cost-effective solution in extreme climates (after co-generation), despite reductions in thermal efficiency due to ground temperature. (The ground source is warmer in climates that need strong air conditioning, and cooler in climates that need strong heating.) The financial viability of these systems depends on the adequate sizing of ground heat exchangers (GHEs), which generally contribute the most to the overall capital costs of GSHP systems".[57] |
blowlamp | 06/08/2023 13:28:19 |
![]() 1885 forum posts 111 photos | The most efficient ground sourced heat supply we have is oil, coal and wood.
Martin. |
Ed Dinning 1 | 06/08/2023 21:04:21 |
39 forum posts | Hi Folks, I seem to have prompted a lively discussion on these topics!
Summarising, we are engineers , used to thinking in a logical way and finding a solution to problems.
There is an Engineering saying, that "dross rises to the surface", from the preceding discussions I conclude that this has happened in public life; politicians of all shades, and their political advisors are guilty of this. From personal experience the higher echelons of the civil service are similarly mired. It is a great pity there are not more Engineers going into public service, finance and the law or should that be justice?
Think carefully when you next cast your vote, but as Churchill said "Democracy is the worst system, apart from all the others!
Ed |
SillyOldDuffer | 06/08/2023 21:33:26 |
10668 forum posts 2415 photos | Posted by blowlamp on 06/08/2023 13:28:19:
The most efficient ground sourced heat supply we have is oil, coal and wood.
Martin. Three wrongs in one sentence! I won't explain why because Brandolini's Law applies. I'm confident Martin can't justify his claims, but I sure we all want him to try. Watch this space! Dave |
JA | 06/08/2023 21:49:14 |
![]() 1605 forum posts 83 photos | Posted by Ed Dinning 1 on 06/08/2023 21:04:21:
Hi Folks, I seem to have prompted a lively discussion on these topics! It is a great pity there are not more Engineers going into public service, finance and the law or should that be justice? Think carefully when you next cast your vote, but as Churchill said "Democracy is the worst system, apart from all the others! Ed Well done Ed. You have kept quite a few members out of their workshops (if they still have one). Engineers are not stupid enough to go into politics. I agree with Churchill although I do not think much of the man. George Orwell said something like "there is only one thing worse than voting and that is not voting". JA Edited By JA on 06/08/2023 21:50:36 |
Chuck Taper | 06/08/2023 23:55:56 |
![]() 95 forum posts 37 photos | Posted by Tony Pratt 1 on 03/08/2023 10:41:08:
Posted by Chuck Taper on 03/08/2023 10:35:36:
Major embolism inducing rant: There is no uncontrolled worldwide population growth. In fact (global) population growth is slowing and will begin to decline mid century.
Mr Chuck taper, how in gods name [sorry god] do you know population growth will slow and decline by mid century. Tony
Start here https://population.un.org/wpp/Graphs/Probabilistic/POP/TOT/900
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Ady1 | 07/08/2023 01:03:33 |
![]() 6137 forum posts 893 photos | I seriously doubt that human population growth will ever stop The poor reproduce at an amazing rate and capitalism always produces loads of poor people Arab countries double every 30 years, Africa is a disaster zone, South America is trying to flit to North America China is trying to help by digging up and burning the entire planet to try and emulate the wests level of wealth and stabilise its population Pompei was a huge eye opener for me It used to be a moderate town with Herculaneum up the coast a bit Now the entire area is completely blanketed with houses apart from the immediate caldera around Vesuvius The human rat has expanded at a phenomenal rate AD79 Pompeii is going to look like a minor incident if that thing blows again I found the google picture, it's here Edited By Ady1 on 07/08/2023 01:07:26 |
derek hall 1 | 07/08/2023 07:19:09 |
322 forum posts | What happened to Tidal Energy? In the Severn river the tidal range is the second highest in the world. We are an island surrounded by strong tida water, surely there is a way to harness this without too much stress on the environment? Or is it that the money isn't there due the the usual short sightedness of the politicians. It's taken years to agree to a new power station at Sizewell, it will take years to build it. HS2 is well over budget and is now a smaller project than it was originally planned. Crossrail took years to build went over budget and time to construct was longer than planned. It seems any major project or change to infrastructure we cannot do very well anymore, the issue with all these grand schemes is that takes much longer to build and costs more than original costs. I guess it's due to lack of strategic long term planning or is it a lack of knowledgeable qualified people at the top who are capable of making informed decisions.? |
Robert Atkinson 2 | 07/08/2023 07:51:30 |
![]() 1891 forum posts 37 photos | Much of cost and delays to these major projects is due to opposition from various groups and the complex planning approval process. Nuclear, is currently the only viable mid-term solution to base load power production. This position would be strengthened if their excess power is used to produce hydrogen. This could be used to run gasturbines for peak load response. There is a huge amount of money being made from carbon off-setting, biomass etc. IMHO there is too much emphasis on hitting numeric targets rather than finding real solutuons. Even without the carbon of harvesting, processing and shipping (often across the atlantic) of wood pellet "biomass" it produces more CO2 per kWh produced than burnng gas.... At last in the news recently there has been some coverage of the shortcomings of the power network to accept additional power into the network and supply it to were needed like motorway EV charging stations. This is my personal opinion and may not reflect that of my employer or other organisation I may be associated with. (I do some work on this stuff as part of my day job and a disclamer is required). Robert. |
Michael Gilligan | 07/08/2023 07:58:09 |
![]() 23121 forum posts 1360 photos | Posted by derek hall 1 on 07/08/2023 07:19:09:
What happened to Tidal Energy? In the Severn river the tidal range is the second highest in the world. We are an island surrounded by strong tida water, surely there is a way to harness this without too much stress on the environment? […] . I’m not so sure about that, derek Most of us are probably old enough to remember the popularisation of Chaos Theory and its powerful anecdotal image of the beat of a butterfly’s wing. In our headlong rush to extract ‘renewable’ energy from every available nook & cranny … I wonder what we might trigger next. MichaelG. |
Anthony Knights | 07/08/2023 08:17:02 |
681 forum posts 260 photos | I seem to remember reading some where that extracting energy from the tides would slow the earth's rotation down? |
Nigel McBurney 1 | 07/08/2023 09:35:28 |
![]() 1101 forum posts 3 photos | Does the investment on solar panels,various source heat pumps really pay off , the initial cost is high,whats their life before replacement is necessary? already there are complaints that servicing is a problem,my neighbour has solar panels but the controls and battery take up a surprising amount of internal dwelling space and already he is thinking about battery fire risk and looking at possibly placing the battery outdoors . I run my heating on oil,plus woodburner ,the boiler is the latest type as I could not find a relacement of the old type ,the new boiler uses the same amount of fuel,though I have heard the new gas boilers are more efficient, plus the new boiler is not so reliable,already had new oil pump.Woodburning is not cheap unless there is a free or cheap supply of wood,and to process and store wood to its well dry at times I have stored up to 100 cu yards of wood possibly more, plus a good log splitter is required plus a lot of work, Being out in the sticks a woodburner has served us well in times of power cuts and the current cost of oil.the earth wouls get along quite well by itself without humans, a few events over hundreds of million years has caused major wipeout of life but the planet has survived,though now its obvious that the earth can ony sustain a certain number of humans, only a collision with a lump of rock from space or a plague will regain the natural balance, nature seems to balance itself until man interferes, the black death did reduce the poulation perhaps another event could reduce the population by 50% and save us, .
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Ady1 | 07/08/2023 09:54:02 |
![]() 6137 forum posts 893 photos | Once we get off-planet we'll be fine We need a Frank Whittle 2 to invent warp drive then Musk-Intergalactic for transport All the gadgets and gizmos like fusion and crop splicing are only going to delay the inevitable for a species stuck in a glass bowl slowly getting grottier and grottier until it becomes uninhabitable |
Clive Steer | 07/08/2023 10:14:17 |
227 forum posts 4 photos | I think there is a certain amount of hype about all the "alternative" sources of energy. For instance heat pumps are being hailed as the saviour and efficiencies of 300% are being quoted. However these are the best and actuals may be less when outside air temp is low and may reduce to zero if OAT is very low. The downside of this is that just when you need heat it can't supply it. There are also difficulties heating to the 40C needed for our style of wet convection radiator systems. Better efficiency may be obtained if convection radiators are "blown" or hot air used directly. However the biggest problem is that a large proportion of our housing stock has poor thermal performance which can be very costly to improve. I'm not sure that even modern houses are built to the best thermal performance achievable at moderate cost so these properties will become too costly in the future. If we all move to heat pumps plus electric cars our Grid will have to double or even triple in capacity. The plan is a good idea but we should have started it 50 years ago! CS |
John Haine | 07/08/2023 10:25:39 |
5563 forum posts 322 photos | Posted by Anthony Knights on 07/08/2023 08:17:02:
I seem to remember reading some where that extracting energy from the tides would slow the earth's rotation down? Well, sine ALL the energy in the tides is already dissipated by hydrodynamic friction with the land we are already doomed! |
Bob Worsley | 07/08/2023 10:33:41 |
146 forum posts | As CS says, is this 300% efficiency real? I asked earlier if anyone had real data they could present, none so far. My experience of messing with aircon units is that the electricity they use to run the compressor and fans doesn't make for any great efficiency, considering the cost of buying the unit in the first place. Of course, then the grid is overloaded and get blackouts then efficiency drops to 0%. As for water temperature, if radiators are designed for 70C then obviously going to be colder with 40C, but why not just run the water pump for 12 hours per day rather than 3 hours? Electricity obviously, but heat output per 24 hours will be the same.
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JasonB | 07/08/2023 10:39:23 |
![]() 25215 forum posts 3105 photos 1 articles | heat pump will need to run for longer as OAT drops as it can only extract a certain wattage/hr. 300% is possible on a hot day but drops a lot when you avarage it out over a whole year. Really best suited to UFH where there is plenty of insulation under the slab and the slab acts as a heat store and doe snot need to be as hot as a radiator They are now very popular for heating ponds and swimming pools, partly because the pump is running to filter the water anyway so that reduces the cost of running considerably and you also have a big heat store that only need sto be heated to 25-30deg Edited By JasonB on 07/08/2023 10:40:31 |
Graham Meek | 07/08/2023 11:23:50 |
714 forum posts 414 photos | As regards Tidal power Guy Martin showed a system in operation off the coast of Scotland, (I think it was). It had two underwater turbines which were either side of a moored pontoon. Why aren't there more of them, good question. After all as long as the Moon is there we will have energy. The tides do not stop so it is constant energy. I suspect the answer to the question is the Grid is not there to bring the power ashore. It would also suit the NIMBY's as they are virtually invisible. As regards the Severn, a Barrage has been proposed on more than one occasion. This would have provided a roadway as well, but like all these suggestions it was kicked into touch. I think the French built one, and of course you get power on the incoming tide and on the out going tide. As regards politics, I have no inclination to even try banging my head against a brick wall. "There is too much we have always done it that way involved" Although the pay and holidays are very good. Regards Gray, Edited By Graham Meek on 07/08/2023 11:26:18 |
blowlamp | 07/08/2023 12:05:14 |
![]() 1885 forum posts 111 photos | Posted by SillyOldDuffer on 06/08/2023 21:33:26:
Posted by blowlamp on 06/08/2023 13:28:19:
The most efficient ground sourced heat supply we have is oil, coal and wood.
Martin. Three wrongs in one sentence! I won't explain why because Brandolini's Law applies. I'm confident Martin can't justify his claims, but I sure we all want him to try. Watch this space! Dave
They are the most efficient sources because they are readily available and straightforward to process. If we could extract electricity directly from the ground or wherever, store it indefinitely with little loss and transfer it quickly & easily in dense energy form, then that might be a preferable alternative. Which more efficient, ground sourced heat supply, alternative fuels are you using to power your existance?
Martin. |
SillyOldDuffer | 07/08/2023 12:07:58 |
10668 forum posts 2415 photos | Posted by derek hall 1 on 07/08/2023 07:19:09:
What happened to Tidal Energy? In the Severn river the tidal range is the second highest in the world. We are an island surrounded by strong tida water, surely there is a way to harness this without too much stress on the environment? ...I guess it's due to lack of strategic long term planning or is it a lack of knowledgeable qualified people at the top who are capable of making informed decisions.? The problem is a combination:
Wave energy is promising, but the engineering is difficult and looks to be high-maintenance. It's easier to build large towers with a wind turbine on top, they're easier to maintain. Geothermal is also promising with challenging engineering - a couple of wide-bore holes potentially several miles deep, penetrating into the magma to create super-heated steam. The theory is straightforward, but we don't have the technology or need yet. I don't think the issue is lack of expertise at the top. We're talking big money and significant change versus vested interests and a lot of people who fear losing out and don't understand the science. They think it's a political argument, when the Laws of Physics are in charge. Thermodynamics aren't influenced by human opinion. Add more heat to the environment, and what happens next follows physical laws, not human wishes. It's a nasty situation: those who understand the science know full well bad things are happening and have several ways of reducing the damage. Unfortunately, they haven't been able to persuade those who don't understand the science, and those who don't want to. It's a mess. Regret to say that those who don't understand have so far won the argument, and not enough has been done. In consequence the original target of allowing a 1.5°C increase in average temperature is now unachievable, and the new target will be between 2 and 4°C. Things will change, because we've gone beyond warning of trouble ahead. Now, man in the street is starting to notice something odd is happening to the weather. Climate is difficult for individuals to comprehend, but rapid sequences of record breaking rainfall, storms, heat-waves, freezes, droughts are harder to ignore. Reality always wins in the end. The danger is public opinion is swinging far too slowly to avert seriously rough times ahead. Politicians fail because they can't afford to upset their supporters, even if they know their supporters are completely wrong. The Laws of Physics care absolutely nothing for human affairs, left or right. Dave |
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