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SteamyTea

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Everything posted by SteamyTea

  1. Thanks, not a huge difference. 13 kWh is just more than a days usage for me this year.
  2. Do you still have to get planning permission for system greater than 9 m2. I have also never known if that is the area of the panels, or the ground area, or even if a contiguous installation only.
  3. Get a quote. One thing electrical technicians hate doing is verification and sign off of others work.
  4. So it has been a sunny week, but chilly air. Has anyone noticed an upright in their PV production? If you can compare it to the same week, from previous years, that would be really useful.
  5. Has a thermal conductivity of about 0.035 W.m-1.K-1. So a U-Value of 1.75 W.m-2.K-1. So a lot of power will go into the ground. If I was at home, with a blank spreadsheet open, I would take a stab at how much goes into the room, and how much into the ground. But let us say you have 20mm of liquid screed above the pipes (same thickness as XPS below them). The U-Value would be 110 W.m-2.K-1. Now the temperature differences have to be taken into account. Initially let use say that the mean flow temperature though the pipes is 30°C, ground temperature is 8°C and room temperature is 20°C. Power to ground will be 1.75 [W.m-2] x 1 [m²] x (30 - 😎 [K] = 38.5 W.m-2. Power to room will be. 110 [W.m-2] x 1 [m²] x (30 - 20 [K] = 1100 W.m-1. Now for some reason those numbers do not look right to me, so maybe I have made a mistake somewhere (very likely) or I have picked up some duff k-Values. A 3 to 1 difference just does not look right. But if it is right, then a third of your cash is warming worms.
  6. Horrible unit. A TOG is thermal resistance, so the R-Value. 1 TOG is equal to R-Value 0.1 m2.K.W-1. Or in Roman Catholic U-Value 10 W.m-2.K-1. Why don't we all just use the easy to understand SI units, for everything. Not as if there are many if them, or difficult to visualise.
  7. I would like to see the detail options for these joints. When we used to manufacture large, bespoke GRP structures i.e. mosque domes, hospital walkway, external cladding (hard to believe that the fire regs were so loose in the 70s and 80s) I can never remember an SE being involved, even after I raised concerns about thermal expansion/contraction, let alone settlement. The only times I can remember proper engineers being involved was with aviation railway work, but they took a safety first attitude. We did a cabin mockup for Airbus that was used for training, even that was rigourously designed and tested, especially for fire and smoke.
  8. Cement screed has a thermal conductivity of about 1.1 W.m-1.K-1. Liquid screed is about double, so 2.2. Probably best never to put timber above UFH.
  9. OSB has a k-value around 0.13 W.m-1.K-1 at a density of 650 kg.m-3.
  10. Can't really comment on cost, but it probably limits the size of panels you can incorporate into the roof. Do a costing with a roof integrated system i.e. GSE. Then tell your architect to stop spending your money. Also look at the estimated yield from PVGIS as the angles are not optimal.
  11. Makes you a (expletive deleted)ing giant in Cornwall. Shall call you Bolster Build.
  12. With any fixing, it is not just static loads you need to consider. Jerk is important.
  13. Are they really that much now. 11 quid, boils tap water. https://www.argos.co.uk/product/3362910
  14. Only about twice as long as Cornwall then.
  15. Gas cooking is quite inefficient, masked by how hard it is to measure the gas usage. I am intrigued as to why you are reducing hob usage; one pot meals are generally quick and easy, and has to be better than lighting up a 6 kW oven, or even a 2.4 kW microwave. I have just popped my induction hob on, small 'ring' middle setting, it draws 180W. Now I don't have a gas hob to compare it to, but my camping stove is 3 kW, so even at 'half power' it is drawing 8 times the amount of power. I once did a time comparison between a small portable induction hob and my camping stove, but can't remember the results (they are probably buried on this site somewhere, though it may have been on eBuild), was a while back).
  16. Welcome @Mike DC I like a renovation. @saveasteading has been doing a major restoration up your way.
  17. What power rating is the immersion heater? Stratification is a bad term to use when describing fluids. It implies a very distinct change in temperature at a fixed position. Think of it as geological stratification. In reality, there will be a temperature gradient from bottom (colder) to top (hotter) once there is no fluid mixing happening (given time to settle down). As electrical immersion heaters are generally fitted low down in the vessel, and when powered, are very hot (maybe 650K), it is not unusual for water vapour to be created on the surface of the element. This vapour will bubble away upwards, causing a chaotic turbulence in the fluid (water in this case). Some of this gas will reach the top of the vessel as steam (steam is the term used for water at phase change temperature between liquid and gas). Steam is a dangerous material. While only at 373K (100°C) as it cools, the entropy of vaporisation is 2257 kJ.kg-1, so 550 times more energy is realised compared to liquid water dropping 1K in temperature (vaporisation and fusion have not delta T). So if you are getting visible water vapour coming out of the tap, you have a very dangerous situation (think pulling the cling film off the top of some over microwaved soup, the steam really hurts). You may find that fitting a smaller heating element will reduce, or even eliminate, the overheating. It is possible to design a system that is intrinsically safe by balancing the energy input to the totally storage system losses, governing the maximum water temperature, though they can take a long time to heat up. Thank goodness for PRV, which should really be called ERV (energy release valves).
  18. I like that. Shall suggest one for work to the commandant.
  19. Your garden looks about the same size as mine. Do you intend for it to be used as a garden, or, like me, an extension of the shed. I just put down a membrane and then 20mm granite chippings. All my plants are in pots.
  20. Working as a chef, the easy way to make a kitchen much more efficient, is to make it smaller. I work in an area not much more the 1m2. Get rid of the clutter i.e. all those containers, gadgets, spice racks etc. Draws are often more useful than cupboards. Put lightweight things higher up. Clean up as you go along. And the big one. Learn how to cook. You really don't need much equipment, or ingredients. There are some dishes you will not create as well as a restaurant. Go to a restaurant for those meals, KISS at home.
  21. Gloss black isn't so bad at reflective. Though it may not stay gloss for long. If you want to know more, then here. https://en.wikipedia.org/wiki/Albedo There is more to it than just colour.
  22. @Gone West Thanks I am assuming there is a typo in the datasheet. 9.3 kW input seems a bit high for a 6 kW HP.
  23. Kind of unit that would also suit me. They have 2 left in stock. But where is the data sheet about it?
  24. Plug types https://traveladapterguide.com/plug-socket-types/ Spanish https://traveladapterguide.com/type-c/
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