SteamyTea Posted February 27, 2018 Share Posted February 27, 2018 Sizing is about knowing your heat loads and temperature ranges. Then the juggling starts which is based on the specific heat capacity of water which s 4.2 kJ.kg-1.K-1, which is 0.k00116667 kWh.kg-1..K-1. kg-1. To be on the safe side, and to save doing solution to partial differential equations (or partial solutions to differential equations as I prefer to call them) that take the form δT/δt(x, y, z) = 0, we usually just sum all the inputs and outputs and then add a bit for a laugh. So you have a store that can hold 450kg of water and it has an input temperature of 10°C and you could just get away with a 60 lt shower at 40°C. That is a gnats under 16 kWh. The shower only uses 2 kWh of that, so you are left with 14 kWh for space heating. But not quite as you have to take into account the minimum temperature required for your space heating needs. So say that is 35°C, you then have, in effect, 390 kg of water to play with, so that works out at only 2.3 kWh left over for space heating. (You can see why space and DHW should really be separate). So iterating again but with a TS temperature of 60°C 0.00116667 [ Wh.kg-1..K-1] . 450 [kg] . (60 - 10) [K] = 26 kWh Take away the 2 kWh for a shower, then you have 24 kWh for space heating. This does not take into account any provisions for thermal losses (pretty high on a TS at 60°C over a day) or extra inputs during the day. There is a lot of criticism about about system sizing, but it really is quite limited and is usually based on the worse case i.e. coldest weather, limited input time period, maximum hot water requirements. This accounts for what can seem like extremely large TSs put into places 5000lt is not unusual. 1 Link to comment Share on other sites More sharing options...
Nickfromwales Posted February 27, 2018 Share Posted February 27, 2018 1 hour ago, SteamyTea said: 5000lt is not unusual. Thats bedroom 3 gone then Good news from the guys that supplied the boiler. It can be programmed to revert to open pipe and ignore the low pressure cut-out / fault switch. Thats the PHE and the PHE pump out of the window, and the boiler free to pump at full wallop directly into the TS. Why the feck they didn't do that originally is beyond me. Hey-Ho. 1 Link to comment Share on other sites More sharing options...
SteamyTea Posted February 27, 2018 Share Posted February 27, 2018 8 minutes ago, Nickfromwales said: Why the feck they didn't do that originally is beyond me. Hey-Ho. Because they had never fitted one before. They are probably fitting heat pumps now. 1 Link to comment Share on other sites More sharing options...
newhome Posted February 27, 2018 Author Share Posted February 27, 2018 2 hours ago, Nickfromwales said: Why the feck they didn't do that originally is beyond me. Hey-Ho. In fairness I think half the problem is down to my maverick husband who would have spoken to a few people / suppliers, got specs for the products that a specific company supplied and then thought he could design it and fit it himself. In hindsight (ain't that always the way! ) we should have got an expert in to design the whole thing holistically with a detailed spec that brought it together as a working system rather than individual components bolted together making the whole thing not fit for purpose. And when he had trades in to help with bits and bobs they would have fitted their own thing and not worried about the rest of it working (understandably). Add to that the fact that no one we had out to help with plumbing had ever worked on anything like it and it compounded the issues. Or alternatively he should have fitted an oil boiler and radiators like everyone else round here, but he was into gadgets and technology so hell would have frozen over before he would have fitted a system like that. We had specs for all sorts when he was deciding what he wanted to build re the house and the components in it. Bloody place is a nightmare now that I'm here on my own. Perhaps his own special way of making sure I remember him I guess . 3 1 Link to comment Share on other sites More sharing options...
newhome Posted February 27, 2018 Author Share Posted February 27, 2018 4 hours ago, SteamyTea said: There is a lot of criticism about about system sizing, but it really is quite limited and is usually based on the worse case i.e. coldest weather, limited input time period, maximum hot water requirements. This accounts for what can seem like extremely large TSs put into places 5000lt is not unusual. Jeez, I'll just put a swimming pool in shall I and use that as me TS! 1 1 Link to comment Share on other sites More sharing options...
SteamyTea Posted February 27, 2018 Share Posted February 27, 2018 14 minutes ago, newhome said: Jeez, I'll just put a swimming pool in shall I and use that as me TS Was tried in Corby. They used a lake to dump excess heat from the leisure centre. They forgot about evaporation losses. Link to comment Share on other sites More sharing options...
newhome Posted February 27, 2018 Author Share Posted February 27, 2018 14 minutes ago, SteamyTea said: Was tried in Corby. Corby? Explains a lot Actually their EV infrastructure is pretty decent. Well that’s if the locals let you use it. This is the charge point I was trying to use, with the second photo of the car park for context! The third photo is the same scenario the next day so not a one off. Link to comment Share on other sites More sharing options...
SteamyTea Posted February 27, 2018 Share Posted February 27, 2018 That is more cars than I have seen at the Land's End charging point. Link to comment Share on other sites More sharing options...
newhome Posted February 27, 2018 Author Share Posted February 27, 2018 (edited) 3 minutes ago, SteamyTea said: That is more cars than I have seen at the Land's End charging point. Yeah but none of the bastard things parked there are EVs (apart from mine)! There's all that bloody room and they choose to block the charging points! Edited February 27, 2018 by newhome 1 Link to comment Share on other sites More sharing options...
SteamyTea Posted February 27, 2018 Share Posted February 27, 2018 I had to plug my car in today. The cold did my battery in. £14 quid for a charger and after a couple of extra cuppas, it was as good as new. Quite surprised that the battery is the original one, so 12 years old. Lead acids are great. Just going to wait till the summer to buy a new one. Today is probably not the cheapest day to get a new car battery. Link to comment Share on other sites More sharing options...
newhome Posted February 27, 2018 Author Share Posted February 27, 2018 2 minutes ago, SteamyTea said: I had to plug my car in today. The cold did my battery in. £14 quid for a charger and after a couple of extra cuppas, it was as good as new. Quite surprised that the battery is the original one, so 12 years old. Lead acids are great. Just going to wait till the summer to buy a new one. Today is probably not the cheapest day to get a new car battery. You have an ICE I assume? I have another big gadget the hubby wanted, a PHEV. He wanted a full EV and I said no bloody way was going to have to stop to recharge when I drove daan saaf. So we compromised on the PHEV which gets me to the station and back easily using electric only but it's quite a large, heavy 4x4 so not incredibly efficient on long journeys, especially as I don't hang about . There are bundles of things still to do for 2040. The technology needs to be improved massively before then, as does the charging infrastructure. Not insurmountable but they'd better get a crack on. And charging people more to use the electric points than it costs in petrol / diesel to travel the same distance is not the answer! Link to comment Share on other sites More sharing options...
newhome Posted February 27, 2018 Author Share Posted February 27, 2018 5 hours ago, SteamyTea said: This does not take into account any provisions for thermal losses (pretty high on a TS at 60°C over a day) or extra inputs during the day. Bringing this back to heating ....... How well insulated are TSs? I was surprised that mine has no extra insulation on the outside TBA so assumed that they had amazing insulation inside but maybe not? Link to comment Share on other sites More sharing options...
SteamyTea Posted February 27, 2018 Share Posted February 27, 2018 "Batteries are rubbish". James May, Top Gear, 31 July 2011 Link to comment Share on other sites More sharing options...
SteamyTea Posted February 27, 2018 Share Posted February 27, 2018 (edited) 7 minutes ago, newhome said: How well insulated are TSs? I was surprised that mine has no extra insulation on the outside TBA so assumed that they had amazing insulation inside but maybe not? Pretty poor really. You could measure the thickness, find out the material and then work out the thermal losses. Before I secondary insulated my DHW cylinder, I was loosing more than I was using. Oh and don't believe the manufacturers claims, the testing regime is, to say the least, a bit odd. Edited February 27, 2018 by SteamyTea Link to comment Share on other sites More sharing options...
newhome Posted February 27, 2018 Author Share Posted February 27, 2018 7 minutes ago, SteamyTea said: "Batteries are rubbish". James May, Top Gear, 31 July 2011 Yeah but James May is a bit of a twat and a dick petrol head like him is probably against all renewables too ...... Link to comment Share on other sites More sharing options...
newhome Posted February 27, 2018 Author Share Posted February 27, 2018 4 minutes ago, SteamyTea said: Pretty poor really. You could measure the thickness, find out the material and then work out the thermal losses. Before I secondary insulated my DHW cylinder, I was loosing more than I was using. @Nickfromwales can you order a wee jumper for my poor little TS please . I cannae knit so will have to be purchased . Link to comment Share on other sites More sharing options...
SteamyTea Posted February 27, 2018 Share Posted February 27, 2018 (edited) I think he is quite the opposite, he did a good program about energy. Always hard to get a complete picture across on a short program. And he did bother to reply to me once, or twice. https://drivetribe.com/p/internal-combustion-its-all-a-bit-YZGOUlf-RnKJY2S4fdl0_w?iid=DUUZjFaPToGbFv4oPrbYPA worth pointing out that my first stint at university was studying Automotive Engineering Edited February 27, 2018 by SteamyTea 1 Link to comment Share on other sites More sharing options...
Ferdinand Posted February 27, 2018 Share Posted February 27, 2018 (edited) 7 minutes ago, newhome said: Yeah but James May is a bit of a twat and a dick petrol head like him is probably against all renewables too ...... He has nice shirts. People keep comparing them to my Jeff Banks items. Edited February 27, 2018 by Ferdinand 1 Link to comment Share on other sites More sharing options...
SteamyTea Posted February 27, 2018 Share Posted February 27, 2018 But back to energy storage (almost) To store 24 kWh as gasoline would take about 2.5 lt. Link to comment Share on other sites More sharing options...
Nickfromwales Posted February 27, 2018 Share Posted February 27, 2018 1 hour ago, SteamyTea said: Was tried in Corby. They used a lake to dump excess heat from the leisure centre. They forgot about evaporation losses. Isn't steaming fish healthier? 1 Link to comment Share on other sites More sharing options...
SteamyTea Posted February 27, 2018 Share Posted February 27, 2018 6 minutes ago, Nickfromwales said: Isn't steaming fish healthier? Not for me, what to see what fingering fish does to my skin 1 Link to comment Share on other sites More sharing options...
Construction Channel Posted February 27, 2018 Share Posted February 27, 2018 32 minutes ago, newhome said: There are bundles of things still to do for 2040. The technology needs to be improved massively before then, as does the charging infrastructure. Not insurmountable but they'd better get a crack on. And charging people more to use the electric points than it costs in petrol / diesel to travel the same distance is not the answer! well worth a watch, according to this guy 2040 will be easy....... FWIW I do like the idea of EV's, I like it so much I have hired a Tesla Model X P100d Ludicrous+ for our wedding day, And yes i obviously do need it for 3 days Link to comment Share on other sites More sharing options...
Onoff Posted February 27, 2018 Share Posted February 27, 2018 1 hour ago, SteamyTea said: Was tried in Corby. They used a lake to dump excess heat from the leisure centre. They forgot about evaporation losses. A complete aside but what you would assume were originally decorative ponds at the Barbican Centre in London were originally cooling ponds for the ac. 1 Link to comment Share on other sites More sharing options...
newhome Posted February 27, 2018 Author Share Posted February 27, 2018 2 minutes ago, Construction Channel said: well worth a watch, according to this guy 2040 will be easy....... FWIW I do like the idea of EV's, I like it so much I have hired a Tesla Model X P100d Ludicrous+ for our wedding day, And yes i obviously do need it for 3 days Will have a watch - cheers. Of course you need it for 3 days. Who would think otherwise? . Hubby wanted a Tesla Model X but far too expensive! They are supposed to bringing the Model 3 out "shortly" followed by the Model Y with a fab electric range which from an affordability perspective as well as range should bring them back into view for a much larger consumer group! Now that the Gov subsidy has been cut the almost 40k price of the PHEV is way too high in my view. I won't be buying another unless the price drops and the electric range is improved. Link to comment Share on other sites More sharing options...
Nickfromwales Posted February 27, 2018 Share Posted February 27, 2018 27 minutes ago, newhome said: Bringing this back to heating ....... Prob best 22 minutes ago, SteamyTea said: You could measure the thickness, find out the material and then work out the thermal losses. Before I secondary insulated my DHW cylinder, I was loosing more than I was using. Lagging all the pipework is more critical than people give credit to. With a TS, and within my proposal to pull this system into line, will be the addition of motorised valves on the boiler flow, the 2x UFH flows, and the provision of an anti-gravity convection valve on the primary feed to the DHW PHE so no unwanted heat flow occurs the the system is in 'standby' eg between heating input events / summer mode, so the ST is kept purely for DHW. That TS has, if Telford's is anything to go by, around 40mm of injected PIR under the full metal jacket, so shouldn't be too shabby. 1 Link to comment Share on other sites More sharing options...
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