Advertisement
If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie

Are you all pleased with your solar panels for hot water heating

2456714

Comments

  • Registered Users Posts: 5,112 ✭✭✭homer911


    macnab wrote: »
    cost: €6000 ish
    year of installation: 2002
    m2 area: 5m
    orientation: South, 37deg elevation
    flat plate or tubes: Flat Plate
    cylinder size: 300 litre dual coil
    summer heat dump strategy: have lots of baths!
    Max temp observed: 97 deg C

    I had a contractor fit the panel to the roof but i installed the rest.
    The pump costs less than €20 a year on leccie.

    I hope they fitted an anti-scald device (and that you live in a soft water area) - what happens when you go on holidays?


  • Closed Accounts Posts: 71 ✭✭steveq


    Hi,

    I should have said that I am in Dublin 14.


  • Hosted Moderators Posts: 3,290 ✭✭✭TomTom


    I am doing a new build in the Offaly area, could someone PM me a recommended supplier. I went to the self build show in Galway two weeks ago and outside the event there was two different solar displays. I visited both there was a 10degree difference between them so it's safe to say there are big differences between each technology and supplier. Any advice appreciated.


  • Closed Accounts Posts: 5 rockie2010


    championc wrote: »
    cost - €5000
    year of installation - 01/2010
    m2 area - 3m2
    orientation - Due South about 25 deg pitch
    flat plate or tubes - tubes (30)
    cylinder size - 180L
    summer heat dump strategy ( if any ) - None

    Delighted with system. With lower volume of water, this allows for higher potential rise in temperature. Remember, you have to raise the WHOLE store of water 1 deg C at a time. I also went for an option for the controller to be able to store my data - useful for spotting any problems in the future in addition to seeing the real benefits of the system.

    Here's my data from a Sunny day 15 June 2010. Temperature rise of Store of 30 deg C
    15062010.jpg
    Hi ChampionC
    Any chance you could show 12 months of data?
    thanks


  • Registered Users Posts: 6,031 ✭✭✭championc


    Each month would be a completely separate screenprint so that would be 12 for a year. Maybe I'll try and do a selection of months like Apr thru Sep or is there any months in particular that you are interested in ?


    C

    Sofar ME3000 Battery Storage Inverter for sale in Ballinteer, Sth. Dublin - see Adverts.ie - https://www.adverts.ie/other-electronics/solar-sofar-me3000-battery-storage-inverter/32914042 or PM me



  • Advertisement
  • Registered Users Posts: 6,031 ✭✭✭championc


    How's this for you - remember, I do not use anything (Immersion or Central Heating) to hop up this water so every degree and litre is solar heated. The temperatures indicated are those from the Top of the Storage Tank (180L)

    Apr-Jul.jpg

    Sofar ME3000 Battery Storage Inverter for sale in Ballinteer, Sth. Dublin - see Adverts.ie - https://www.adverts.ie/other-electronics/solar-sofar-me3000-battery-storage-inverter/32914042 or PM me



  • Closed Accounts Posts: 5 rockie2010


    championc wrote: »
    How's this for you - remember, I do not use anything (Immersion or Central Heating) to hop up this water so every degree and litre is solar heated. The temperatures indicated are those from the Top of the Storage Tank (180L)

    Apr-Jul.jpg

    Heh ChampionC
    thanks a million- I like the feedback its giving you. I had a system installed last week and its only getting up to 55C at the collector (today which was sunny) and 53C about half way up the tank. (30tubes facing south 300L tank) I'm not convinced the system is working correctly so wondered what variation to expect. Your results are telling me that it might just be normal variation but likely to be either a rubbish system or its incorrectly installed.. I'll see how it behaves over a week or so. Any chance you could post your June 2011 data for Roof, Bottom and Top tank?
    Rockie2010


  • Registered Users Posts: 6,031 ✭✭✭championc


    Here's my data from yesterday so that you have something to go on with. My system is a Kingspan Thermomax (I believe I can name a brand but not the installer) 30 tube system with a 180L store. The equivalent for a 300L store to gain the same return would be 50 tubes. My objective was to maximize heat gain during Spring and Autumn. With a totally sunny day in June last year, I got a rise of 30 deg C for the 180L. With 30 tubes and a 300L store I would expect the best you would get would be about 15 deg C.

    Basically, the more water you have stored, the more difficult it is to raise the temp by 1 deg C at a time.

    If you examine my data from yesterday, you'll notice that I had a rise yesterday of about 10 deg C so if you had the same sort of conditions as I had, you could then expect about a 5 - 6 deg C increase but that's about it.

    The advantage of having data is that you can see the system in motion. The roof temp increases (Green) and when about 8 or so deg above the bottom of store temp (Blue), then the pump kicks in and starts transferring heat into the bottom until it gets to the same temp as the top of the store (Red) and then the top and bottom inch up a degree at a time (when the sun is out - you can see when clouds must have come across) until the sun finally falls away just after 18:30. Another bit that is useful is to see the natural loss from the store. I seem to lose about 1 deg C every 2 - 3 hours

    20110530.jpg

    Sofar ME3000 Battery Storage Inverter for sale in Ballinteer, Sth. Dublin - see Adverts.ie - https://www.adverts.ie/other-electronics/solar-sofar-me3000-battery-storage-inverter/32914042 or PM me



  • Registered Users Posts: 1 Mermaid01


    Poll is closed :)

    2,400 euro.

    2010.

    Between 4 and 5 sq. m.

    45 degree pitch. Due S.

    200l stainless triple coil.

    No dump option.

    Very happy, the company I bought from are very helpful, and provide excellent backup. Controller is a snazzy affair, with options to control a backup immersion element, temp settings and a 3 channel timer, as well as control of pump on the feed side (didn't need this as I have rock steady mains pressure, and converted to a non vented system at the same time). House is 12 years old, and well insulated (timber frame-with a lot of retro-fitting going on-I'm doing a major refurb atm).

    Temp is hitting the high fifties with solar input alone at this time of year.


    Hi Roundy,

    Grateful if you could PM the comapny details to me also.

    Thanks.


  • Registered Users Posts: 1,380 ✭✭✭dathi


    as champ says 30 tubes into 300 ltr tank is not enough i have 30 tubes (cheap and cheerful chinese) into 200ltr tank it had the whole tank up to 64* yesterday which is the temp i have the heat dump set at as the water is very limey here in kk


  • Advertisement
  • Closed Accounts Posts: 5 rockie2010


    championc wrote: »
    Here's my data from yesterday so that you have something to go on with. My system is a Kingspan Thermomax (I believe I can name a brand but not the installer) 30 tube system with a 180L store. The equivalent for a 300L store to gain the same return would be 50 tubes. My objective was to maximize heat gain during Spring and Autumn. With a totally sunny day in June last year, I got a rise of 30 deg C for the 180L. With 30 tubes and a 300L store I would expect the best you would get would be about 15 deg C.

    Basically, the more water you have stored, the more difficult it is to raise the temp by 1 deg C at a time.

    If you examine my data from yesterday, you'll notice that I had a rise yesterday of about 10 deg C so if you had the same sort of conditions as I had, you could then expect about a 5 - 6 deg C increase but that's about it.

    The advantage of having data is that you can see the system in motion. The roof temp increases (Green) and when about 8 or so deg above the bottom of store temp (Blue), then the pump kicks in and starts transferring heat into the bottom until it gets to the same temp as the top of the store (Red) and then the top and bottom inch up a degree at a time (when the sun is out - you can see when clouds must have come across) until the sun finally falls away just after 18:30. Another bit that is useful is to see the natural loss from the store. I seem to lose about 1 deg C every 2 - 3 hours

    20110530.jpg

    That is helpful C. I should be thinking of temp gains not absolute temp. I think it did climb around 7 degrees yesterday. I would have gone for that monitoring system if it were offered to me at the time. I don't have a Steca pump station/controller. so not sure it can be retrofitted. I've contacted them.
    R.


  • Registered Users Posts: 6,031 ✭✭✭championc


    My controller is a Kingspan badged Steca TR0603mc. I think all controllers are doing the same thing so shouldn't be a problem. Whatever brand you got, there's probably a version exactly the same as what you have that just has a data logger attached so maybe your installer could simply swap it over (for about 100 extra) and use your current one on his next job. Mind you, it wasn't offerred to me either so I had to somewhat fight for it.

    However, maybe you don't really need it since by the sounds of things, your expectations for the system were possibly higher than the actual reality. You will have to hope for a good run of weather to get the temp up to the levels you're hoping for.

    The one setting which everyone should be vary of the most on their system is the shutoff of the pump depending on the roof temp relative to the bottom of store temp. You cannot have the pump running if the roof temp is the same as the bottom temp since it could then start cooling the store. I think cutoff is 2 deg C on the roof higher than the bottom of the store.


    C

    Sofar ME3000 Battery Storage Inverter for sale in Ballinteer, Sth. Dublin - see Adverts.ie - https://www.adverts.ie/other-electronics/solar-sofar-me3000-battery-storage-inverter/32914042 or PM me



  • Registered Users Posts: 315 ✭✭RTT


    Hi championc. Is there any chance you could pm the installers of your Kingspan thermomax system please as I'm hoping to get that too?

    Thanks

    championc wrote: »
    My controller is a Kingspan badged Steca TR0603mc. I think all controllers are doing the same thing so shouldn't be a problem. Whatever brand you got, there's probably a version exactly the same as what you have that just has a data logger attached so maybe your installer could simply swap it over (for about 100 extra) and use your current one on his next job. Mind you, it wasn't offerred to me either so I had to somewhat fight for it.

    However, maybe you don't really need it since by the sounds of things, your expectations for the system were possibly higher than the actual reality. You will have to hope for a good run of weather to get the temp up to the levels you're hoping for.

    The one setting which everyone should be vary of the most on their system is the shutoff of the pump depending on the roof temp relative to the bottom of store temp. You cannot have the pump running if the roof temp is the same as the bottom temp since it could then start cooling the store. I think cutoff is 2 deg C on the roof higher than the bottom of the store.


    C


  • Registered Users Posts: 39 badger81


    me too roundy or anyone else
    thanks


  • Closed Accounts Posts: 10,910 ✭✭✭✭RoundyMooney


    My apologies to those who PMed me, and who I'm only getting round to now. (edit to add: a ball of my PMs were marked read at some stage, presumably by me, so some of your queries are over a year old-if you did get in touch apologies again, and if you still need info, drop me a line and I'll try not to be *quite* as slow in coming back to you:))

    My supplier, (it was a self install), has ceased doing domestic work, and are now concentrating on the commercial side of things. As I assume they may still supply the gear, I can't name them here, but I'll PM those who contacted me in the hope that they'll get the same great service I did.

    I had a couple of issues down the line, unrelated to the install, or the quality of the equipment supplied, and they could not have been more helpful.


  • Registered Users Posts: 1,682 ✭✭✭firemansam4


    Just a thought on solar.....

    Solar provided hot water. Hot water accounts for 20% of your annual heating bills. Assume worst case that each bill is 300 euro every 2 months so thats

    300 x 6 = 1800

    20% of 1800 = 360

    So if the adverage system seems to be around 3k

    thats a payback time of 8 years.


    that does not include associated costs of maintenance and power used by pumps.

    Granted it meets your green obligations but it does not push the energy rating of your home up much and seems like a long payback for a rethro fit.

    I agree that a condensing boiler costs less and generates more return.

    Hello, I don't have solar panels installed in my house yet, but i used to work installing them for a period of about 2 years. Just one thing that should be mentioned when you are considering the payback period for the cost of the install...

    If you are installing a new stainless steel cylinder for your old copper one it should last a lifetime and you should never have to replace it again, where as you will probably at some stage need to replace your copper cylinder.

    I have worked out the electricity cost for the pump unit if its a good economy one it will cost about 15 euros to run for a year.

    One more thing is that while solar panels do primarily heat hot water, because when your heating comes on it has to pass through your domestic cylinder (through another coil) you will notice the heating doesn't take as long to heat up thus saving you a bit more on heating costs.

    One more point is that even if it does take 8 years to pay for the system, at least you know after that it will be saving you money for nothing. and the way oil prices are going the cost benefit in the future will most probably be far better.


  • Registered Users Posts: 315 ✭✭RTT


    I'm just at the final stages of a putting in a new heating system in my house. Switched from oil to gas, removed gun barrel etc. I planned to get the solar in at the same time but unfortunately my budget won't allow it. I will be putting in a 250L dual coil cylinder and the plumber will run the provision for the solar. Is it ok to use copper with compression fittings or should he be using the stainless steel flexible piping which is more expensive?


  • Registered Users Posts: 1,682 ✭✭✭firemansam4


    RTT wrote: »
    I'm just at the final stages of a putting in a new heating system in my house. Switched from oil to gas, removed gun barrel etc. I planned to get the solar in at the same time but unfortunately my budget won't allow it. I will be putting in a 250L dual coil cylinder and the plumber will run the provision for the solar. Is it ok to use copper with compression fittings or should he be using the stainless steel flexible piping which is more expensive?

    Copper pipes should be fine, although the stainless steel pipe tends to be insulated a lot better as there will be no patching around fittings, but this will be negligible if the copper pipes and fittings have been insulated well.

    The only thing is with every compression fitting you are increasing the chance of a leak on the system. Might be an idea making sure that any fittings in the pipework will be accessible.

    If it was me doing it i would probably try pay a bit extra and put in the Stainless steel piping.


  • Registered Users Posts: 106 ✭✭BrenCooney


    cost, 2400
    year of installation, May 2011
    m2 area, 6
    orientation, south 37 degree angle
    flat plate or tubes, flat plate
    cylinder size, 300l
    summer heat dump strategy ( if any ), no but covered panels while on holidays


    self installed. Put in the 300l tank last year as the copper tank developed a leak and thus i got the go ahead from "the boss" to put in action what i had been planning for about a year previous. so i replumbed the house (S??t builder), put in a new condensing boiler, controller and trv's on the rads. only got around to putting in the panels this May as i was getting the roof insulated in march and april (dormer, completely stripped, vapour block and completely sealed to wall plate, rafters built up to 300mm, insulated with glass fibre, etc U value calculated to 0.12). after the roof was being re tiled i went up and installed the panels with the help of the family pullng on ropes etc.

    very happy with it! Water heating costs have plumeted.


    BrenC


  • Closed Accounts Posts: 6,824 ✭✭✭Qualitymark


    Does the orientation make a huge difference? My roof faces southeast, rather than due south.

    Do these systems just heat washing water, or do they heat radiators as well?

    What's the ideal size for a standard three-bed semi?


  • Advertisement
  • Registered Users Posts: 6,031 ✭✭✭championc


    I'm no expert - just my 2 pence worth.

    Watch your roof and see what time the sun hits the roof in the morning and what time it loses it later in the day. However, given the fact that the air temp is lower in the mornings, it would not quite be as efficient as a SW facing roof.

    As for sizing, you really need 50 tubes with a 300l store (or I have 30 tubes with 180l). It really heats hot washing water but if oversized on the tubes side, could in theory be used to transfer heat from the store into a rads circuit to take the chill out of a house in late spring or early autumn (via a second coil) - that next on my to do list !!


    C

    Sofar ME3000 Battery Storage Inverter for sale in Ballinteer, Sth. Dublin - see Adverts.ie - https://www.adverts.ie/other-electronics/solar-sofar-me3000-battery-storage-inverter/32914042 or PM me



  • Registered Users Posts: 4,748 ✭✭✭Do-more


    Likewise I am no expert but this link let's you input all the various data for your location, orientation, roof pitch etc. and calculate the output of a solar PV panel.
    http://re.jrc.ec.europa.eu/pvgis/apps4/pvest.php#

    By running the calculations for due south and for your actual orientation you can see what drop off you have from the ideal. As it's based on calculating the solar radiation I presume it's also reasonably valid for solar thermal.

    FWIW my roof is also facing south east and the passive house planning program calculates that 8m2 of tubes will give me 69% of my yearly estimated DHW demand.

    invest4deepvalue.com



  • Registered Users Posts: 1,627 ✭✭✭quentingargan


    Does the orientation make a huge difference? My roof faces southeast, rather than due south.

    Do these systems just heat washing water, or do they heat radiators as well?

    What's the ideal size for a standard three-bed semi?
    There is a small fall off when you go from S to SE. About 10%, and slightly more than that if the roof is steep. If you have a SE roof with a 30 degree pitch, that is better than a SE roof with a 45 degree pitch.

    We have a computer simulator that can give precise figures based on your geographical location, roof orientation and pitch and the type of panel used. PM me if you want that.


  • Closed Accounts Posts: 6,824 ✭✭✭Qualitymark


    Our roof is a standard sort of pitch - it's a typical 1930s semi - but I have no idea what that pitch is. Any tips? If I lean out the skylight and put a spirit level on the roof will it show the percentage pitch?


  • Registered Users Posts: 1,682 ✭✭✭firemansam4


    I really wouldn't worry to much about the pitch of the roof, unless it is at a very shallow or deep pitch it wont make too much difference. As for the roof being not due south, i don't think many roofs are, so there would be a loss of efficiency but what we would have recommended as installers would have been to just add a few extra tubes to compensate if you are using vacum tubes that is.


  • Closed Accounts Posts: 6,824 ✭✭✭Qualitymark


    I'm just wondering what figure to put in that calculator, though.


  • Closed Accounts Posts: 6,824 ✭✭✭Qualitymark


    Do-more wrote: »
    this link let's you input all the various data for your location, orientation, roof pitch etc. and calculate the output of a solar PV panel.
    http://re.jrc.ec.europa.eu/pvgis/apps4/pvest.php#

    Unfortunately it's designed for people from another planet than mine. Azimuth? Installed peak PC power? Tracking options? They might as well be speaking Greek.


  • Registered Users Posts: 4,748 ✭✭✭Do-more


    Unfortunately it's designed for people from another planet than mine. Azimuth? Installed peak PC power? Tracking options? They might as well be speaking Greek.

    Firstly as it may not have been obvious, the calculator in the link calculates the amount of electricity generated by a solar photo voltaic panel.

    It will not calculate the amount of hot water you will get from a solar thermal panel.

    The idea was more that you could see for yourself how much a panel mounted on your roof would produce compared to the ideal south facing orientation.

    The Azimuth is the direction in which your roof is facing, so if it is facing directly south you put in 0 and if it is facing due East you put in -90.

    So you only need to pick your location off the map and put in a value for the pitch of the roof and for the azimuth and all other values you can leave at the default.

    The idea was only to demonstrate to you that it is not the end of the world if you don't have a roof facing due south.

    For example my own roof is facing approx. south east (-43) and is at 45 degrees pitch but I lose only 5.2% compared to the optimum for my location which is facing due south with a 37 degree pitch.

    invest4deepvalue.com



  • Closed Accounts Posts: 6,824 ✭✭✭Qualitymark


    @championc What is this 'coil' of which you speak?


  • Advertisement
  • Registered Users Posts: 1,020 ✭✭✭Coles


    @championc What is this 'coil' of which you speak?
    Heating systems (solar, peat pumps, central heating boilers etc) transfer their heat in an 'indirect' way. Basically the warm water in the boiler (or glycol mix in the solar panels) doesn't mix with the water in the cylinder, but rather flows through a section within the cylinder (the 'coil') where the heat is transferred to the water.

    Read up on 'indirect cylinders'.


Advertisement