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rob26440
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« Reply #15 on: May 31, 2009, 07:12:56 PM » |
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XONE,
My 30 x 58mm panel is on a southwest facing roof and at this time of year it starts to get the sun around 8:30a.m. but the southeast roof gets the sun much earlier and I would like to take advantage of that. Problem is it is only a small roof and the largest panel would be a 10 x 47mm.
For the last dew days, with all the sunlight hours, the panel has provided up to 400L of water each day at 63C (2 cylinders). There are 3.5 of us in this house. All adults. 2 are at home full time. The 0.5 is only here at weekends. But one member of the family uses at least twice as much hot water as anyone else in the house. It annoys me to have to use the gas to heat up water when I know that the addition of the 10 tube panel on the southeast roof would result in us having all the hot water we need. When (if) we get down to just the 2 of us, the single panel we have now will be sufficient for 8 or 9 months of the year but maybe not in winter.
So, perhaps you could start off with just one panel on the southwest roof and add another if necessary.
Were you able to see the drawing embedded in the email?
Rob.
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S/E England. 30x58mm tubes, S/W facing 40deg pitched roof, 216L primary and 184L secondary cylinders, TDC3 with home-made, separate controller to switch between cylinders, 15mm tubing with min 25mm insulation.
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XONE
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« Reply #16 on: May 31, 2009, 07:35:55 PM » |
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Were you able to see the drawing embedded in the email?
Rob.
Yes, sorry I should have replied with a thank you, apologies and thank you. Very helpfull. So on reccommendation go for a 20 tube on the southwest roof and add a 10 tube?? on the south east if required? I was going to retro fit the tank as well rather than replace a perfectly good tank. We never use the immersion heater anyway. the tank is probably only 100 liters, maybe a little less. |
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rob26440
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« Reply #17 on: May 31, 2009, 09:05:07 PM » |
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XONE,
I'm not sure about recommending the 20 tube panel. I'm assuming you will have worked out how much hot water you need and then decided on the panel size - taking into account the angle of slope and latitude, etc. I'm using 30 x 58mm tubes and 2 cylinders to meet my requirements - when there is adequate sunshine to provide it of course. There's another thread somewhere on the forum that discusses the performance of the various tube sizes so you can make a more informed decision. Although, I have to confess that when I sized my system it was based on how big a cylinder can I fit in the airing cupboard and how big a panel can I get on my roof. Six months later I added another cylinder in the loft. Now I'm considering a second, smaller panel on the S/E roof to act as a top-up.
Rob.
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S/E England. 30x58mm tubes, S/W facing 40deg pitched roof, 216L primary and 184L secondary cylinders, TDC3 with home-made, separate controller to switch between cylinders, 15mm tubing with min 25mm insulation.
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dhaslam
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« Reply #18 on: May 31, 2009, 11:16:40 PM » |
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South west facing is probably OK. If you have a look at the angle of the summer sun in the few hours around midday. It will shine onto a south west roof fairly well if the roof pitch isn't too high. Twenty tubes is very few, even for two people and you will loose a little with the SW panel.
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XONE
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« Reply #19 on: June 02, 2009, 07:48:15 PM » |
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South west facing is probably OK. If you have a look at the angle of the summer sun in the few hours around midday. It will shine onto a south west roof fairly well if the roof pitch isn't too high. Twenty tubes is very few, even for two people and you will loose a little with the SW panel.
We only have a 100 liter or slightly less tank, I don't want to boil the tank and we're on a strict budget. I was thinking of doing 10 each side as the sun hits the whole roof for most of the day. |
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Richard Owen
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« Reply #20 on: June 02, 2009, 10:12:24 PM » |
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Would you have room to expand the system if 2x10 tubes proves insufficient?
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44 Yingli 230Wp panels feeding into 2x Solar Edge SE5000 inverters .20x 58mm SE, 20x 58mm SW, Solar Thermal feeding 320l thermal store. 10kW heat pump. 300W of Hydro Power . |
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Drawmer
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« Reply #21 on: June 02, 2009, 11:04:46 PM » |
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Right, Have a 20 tube pannel, And can't, even on a super sunny day, get more than luke warm water from the tap. What's up with that? The pannel is run into a twin coil tank which is also connected to a rayburn. Getting tank tempretures of around 350C and pannel temps of about 450C Can anyone help?
Have you sorted out the south facing roof then? |
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Paul Drawmer, Deddington Oxon.
Thermal: 20 X 58mm slimline. 210L twin coil cylinder. TDC3. DAB. internal 'Antman' vent.
PV: 21 X Sharp 185w mono, Diehl inverter.
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XONE
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« Reply #23 on: June 03, 2009, 12:10:22 AM » |
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Have you sorted out the south facing roof then?
Thanks for the concern, this was asked for a friend how diy'ed his own system, he has no internet so I asked for him. Would you have room to expand the system if 2x10 tubes proves insufficient?
Yes |
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Richard Owen
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« Reply #24 on: June 03, 2009, 07:08:47 AM » |
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Would you have room to expand the system if 2x10 tubes proves insufficient?
Yes In which case, I'd stick in the 2 x 10 and see how you get on. |
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44 Yingli 230Wp panels feeding into 2x Solar Edge SE5000 inverters .20x 58mm SE, 20x 58mm SW, Solar Thermal feeding 320l thermal store. 10kW heat pump. 300W of Hydro Power . |
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Brandon
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« Reply #25 on: June 03, 2009, 09:29:31 AM » |
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XZONE are you proposing to put 10 on the SW roof, and 10 on the opposite roof? That would make it a NE facing roof, not a good thing at all, you would be better off with 10 on the SW roof.
Not sure that I have got exactly the right end of the stick here though...
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changing the world, one roof at a time ..."We can't be B&Q astroturfers. That's one conspiracy theory too far. You should cut down on the pot." - Wookey |
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XONE
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« Reply #26 on: June 03, 2009, 07:28:08 PM » |
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XZONE are you proposing to put 10 on the SW roof, and 10 on the opposite roof? That would make it a NE facing roof, not a good thing at all, you would be better off with 10 on the SW roof.
Not sure that I have got exactly the right end of the stick here though...
It's ok, I appreciate the concern, the house sits just off of East/West, going by the line of the roof, the westerly roof faces more south, We get sunlight on the easterly/northerly roof right through till about 3/4pm at this time of year. |
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rob26440
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« Reply #27 on: June 04, 2009, 02:33:23 PM » |
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SW25481
Impressive diags.
Your one pump system is similar to one I had thought about and discussed with a local installer but I didn't like the idea of the additional motorised valves. But it does reduce the number of NRVs. I'll have to dig out my old diag if I can find it. I'm assuming the 2 port Resol valves controlling the flow the panel arrays are only energised when pumping is required. Can they stand the heat of stagnation and the pressure?
Lots of isolation valves (full bore?) to allow the panels to be parallel or series configs. Is that reality or just possibility?
You show a Grundfos Alpha 2 pump. Will you be using it to think for itself or set to manual pump speed? They are rather expensive in comparison to the usual DAB pumps.
(BTW. I loaded up DIA but having a couple of probs – fires up 2 screens but one keeps minimising! Will follow this up on the other thread if I don't sort them out.)
Rob.
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S/E England. 30x58mm tubes, S/W facing 40deg pitched roof, 216L primary and 184L secondary cylinders, TDC3 with home-made, separate controller to switch between cylinders, 15mm tubing with min 25mm insulation.
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XONE
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« Reply #28 on: July 15, 2009, 07:56:59 PM » |
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Are these still available? Can't seem to access them. |
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