General > General Technical Chat

Window screens

<< < (18/18)

MK14:

--- Quote from: tom66 on June 12, 2023, 03:26:52 pm ---I agree, ultimately the heat is just moved so it has to come from somewhere.  I guess such a system would probably approach 100% efficiency at a CoP of >8.5 (haven't done the maths, just intuition).   However, I'm not sure what that would tell you.  Maybe give you a figure of merit for the performance of such a system?  Sounds more like a scientific curiosity than a useful measurement.

--- End quote ---

Presumably, if someone had a great understanding of the gas (Physics) laws.  They could use that (and maybe some other stuff), to calculate the theoretical maximum CoP, at a given input (source) temperature.

I.e.  https://en.wikipedia.org/wiki/Gas_laws

Hence we would know (out of curiosity), what the highest possible CoP value, could be for a perfect heat-pump.  Without violating any laws of Physics, even though technologically speaking, we wouldn't be able to produce a device with such high efficiency ratios.

tom66:

--- Quote from: IanB on June 12, 2023, 03:30:14 pm ---
--- Quote from: tom66 on June 12, 2023, 03:26:52 pm ---I agree, ultimately the heat is just moved so it has to come from somewhere.  I guess such a system would probably approach 100% efficiency at a CoP of >8.5 (haven't done the maths, just intuition).   However, I'm not sure what that would tell you.  Maybe give you a figure of merit for the performance of such a system?  Sounds more like a scientific curiosity than a useful measurement.

--- End quote ---

Engineering comes into it. Every improvement in efficiency comes at a cost (of design, of manufacture, of materials). At some point, the increased cost outweighs the benefit.

--- End quote ---

But why not just measure the CoP?  That is a far more useful figure for the application of a heat pump. 

SeanB:
Mosquitos I have many, and you can hear the difference between possibly getting Zika virus, West Nile virus, Chikungunya virus, dengue, and malaria, just from the different varieties of mosquito that fly year round.

mendip_discovery:

--- Quote from: EPAIII on June 12, 2023, 09:33:57 am ---CO2 is not a pollutant. It is an absolute necessity for plant life.

CO2 levels are just barely just above their all time, in the entire history of the planet, low level. If we remove much of it, we will need a new food source because the plants will start dying out. And then the animals. And then, guess who!

Oh, and the oxygen, which the plants make, will run out too! Choke! Gasp!

Somebody needs to actually think this thing out. NOW!

--- End quote ---

I had a quick google and the data I saw states there has been a massive rise in CO² levels. Given how much we have deforested the planet to further our industrial revolutions. It's not surprising. We need to plant more green stuff.
https://earth.org/data_visualization/a-brief-history-of-co2/

Anyhow, I live in the UK and we don't have a need for window or door screens. We do have occasional spates of lots of flies but not had that for a few years. Though I live in a house where on the hottest day of the year the living room doesnt get beyond 21°C so no need to have the windows open. We do get bees in the house and wasps when it's that time of year but we just learn to let them out.

I have heard of the Scottish "wee midge" but avoided being that far north in the summer so far. I have met thier cousins "Manx Midge" it's all ok being up on the mountain course in the Isle of Man until the wind drops and much like scene from Pitch Black all things change and they begin to devour all life.

Navigation

[0] Message Index

[*] Previous page