Solar Panels/Tubes

S

Sasol

Registered User
Messages
23
Hi,
I have just started a new build - 2,600 sq ft story and a half, south facing.

I have been talking to a plumber about heating the house and domestic water and he recommended Solar Tubes (Thermomax). Just wondering if anyone has experience of using these as opposed to the ordinary solar plates ??

Would they recommend them ? Do they actually heat the water sufficiently on cold/hazy/dull days ?

I'd also been interested in hearing peoples opinions of solar panels and/or heating in general as I have been in two minds whether or not to install solar.

Some people I have been talking to swear by it but others they the investment does not equal the benefit to get got.

Any help/opinions would be greatly appreciated.
 
We spent over 5500 euros on flat plate and they will never pay for themselves. I would have been better off burning the money.If I was back again I would not install them unless I had plenty of money. Make provisions, yes, to install at a later date, but I couldn't advise you to install them.

We also spoke with several other people before we installed our solar system who said they were great and that they had heaps of DHW. I foolishly believed them and have to our own expense installed them. Like you we also have a south facing roof, 40 degree pitch and do not have sufficient DHW. Check this link.

[broken link removed]

all the best whatever you do, optimistic

Sasol said:
Hi,
I have just started a new build - 2,600 sq ft story and a half, south facing.

I have been talking to a plumber about heating the house and domestic water and he recommended Solar Tubes (Thermomax). Just wondering if anyone has experience of using these as opposed to the ordinary solar plates ??

Would they recommend them ? Do they actually heat the water sufficiently on cold/hazy/dull days ?

I'd also been interested in hearing peoples opinions of solar panels and/or heating in general as I have been in two minds whether or not to install solar.

Some people I have been talking to swear by it but others they the investment does not equal the benefit to get got.

Any help/opinions would be greatly appreciated.
Click to expand...
 
Hi,

I installed 6 SQ Metres Flat panels in my new build 3 years ago - Initial Cost was €6000 (including installation) - Got a grant of €1800 approx. 300 litre Tank was supplied - so that was another saving - So real cost was €3600 approx - At that money they are worth it. The grant is gone now for new builds but I suppose there is more competition in the market.

The critical thing is not the panels but a well insulated hot water tank. My tank temp drops about 1 degree an hour on average - So it's 60 degrees at 10pm, it's 50 approx at 8am the following morning for showers etc.

We're in the house 3 years now - We have 1 electric shower but have NEVER used it. In general we always have plenty hot water. Even last week the panels would have worked quiet well. Most people will have oil or some heating on for 1-2 hours a day which will also heat the water - most important thing is to keep it warm afterwards!

During the summer months on the good days the panels heat the 300 litre tank to 90+ degrees and even if the next 24-48 hours are dull etc the water is still hot.

I think the general research on this forum proves that electric showers are very expensive and that no matter how expensive oil gets it would be cheaper to get the oil to heat the water..........
 
wow, that is a high temp to achieve in summer. I NEVER achieved temps in those ranges. Hat pitch is your roof at? Do you mind me asking who supplied and fitted your panels? Do you mind me ask where are you located?
Optimistic

PaddyH said:
Hi,

I installed 6 SQ Metres Flat panels in my new build 3 years ago - Initial Cost was €6000 (including installation) - Got a grant of €1800 approx. 300 litre Tank was supplied - so that was another saving - So real cost was €3600 approx - At that money they are worth it. The grant is gone now for new builds but I suppose there is more competition in the market.

The critical thing is not the panels but a well insulated hot water tank. My tank temp drops about 1 degree an hour on average - So it's 60 degrees at 10pm, it's 50 approx at 8am the following morning for showers etc.

We're in the house 3 years now - We have 1 electric shower but have NEVER used it. In general we always have plenty hot water. Even last week the panels would have worked quiet well. Most people will have oil or some heating on for 1-2 hours a day which will also heat the water - most important thing is to keep it warm afterwards!

During the summer months on the good days the panels heat the 300 litre tank to 90+ degrees and even if the next 24-48 hours are dull etc the water is still hot.

I think the general research on this forum proves that electric showers are very expensive and that no matter how expensive oil gets it would be cheaper to get the oil to heat the water..........
Click to expand...
 
Hi Optimistic,

I live in Kerry - Roof pitch is only 25 degress thanks to Kerry County Council! This doesn't help in the winter but maybe it does in the summer?

Panels installed by Solaris Energy (Macroom Co. Cork). I would say they source good panels as they have been at it for years - after sales service only ok.

In the summer in a average day the panels heat the water to 60-70 degrees and on very good days to 90+ - I think the highest it got was 95
 
We have the tube kind. Brilliant during the summer. Never turn on the immersion during the summer, even have enough for baths. Have an electric shower but never been used. The heat coming from immersion is incredible during the summers months. We even had warm water last week when the sun was shining.
 
Hi

We installed 60 solar tubes last summer and we find them excellent. Apparently the Irish weather is more suited to tubes than flat panels as tubes work from day light instead of sunlight which is what the panels need.

We found a great company called Kedco, they are based in Cork but service the whole country, got great price, service and back up.

Good luck, solar is defo a good choice.
 
rebelgirl09 said:
Hi

We installed 60 solar tubes last summer and we find them excellent. Apparently the Irish weather is more suited to tubes than flat panels as tubes work from day light instead of sunlight which is what the panels need.

.
Click to expand...


Are you sure about this? Can you tell me the make and model of panel?

I understand that tubular panels are marginally better because they catch the sun from different angles as it crosses the sky.
 
I used Solar Panel Ireland in East Cork www.solarpanelireland.com to buy the tubes & we installed ourselves, 3000 sq ft house very long run of pipe from the panels to the cyinder , 100 tubes 4 manifolds . We had had 40C on a 450 liter cylinder ( on the bottom half where the solar is going into it) 3 days last week , the top of the tank was hotter. Last summer we still need the oil to give the cylinder a boost once every 3 days because the weather was so bad., but the summer before the water was hot nearly all the time. You cannot depend on it you need something else to boost the temperature on rainy days but on the sunny ones they are great.
 
I have went to a few self-build shows and while at the stands about solar panels each guy I spoke to said the same things that the tubes are better than the flat panel as they are more suited to the Irish climate, and as Rebelgirl09 said they work on light.

This maybe of interest found it on the following website, [broken link removed]

Summary of advantages; vacuum tubes over flat plate solar panels
[broken link removed]Highly efficient heat generation even at low light intensities (e.g. on cloudy days) [broken link removed]Ability to achieve high temperatures [broken link removed]Improved aesthetics – modern, discreet and elegant design [broken link removed]Smaller footprint - less visually intrusive [broken link removed]Longer lifespan allowing greater return on investment [broken link removed]Each tube on the solar panel is individually replaceable meaning single defective tubes can be replaced rather than the entire panel

 
The thermostat on your mixer is set around 38C for a shower but personally I like it a bit hotter between 40 & 45C .
 
If you want the efficiency of a tube system, but the looks of flat plate, have a look at the solar focus panels. I have fitted them and am delighted with the way they look, haven't got hot water up and running yet though so afraid I can't comment on performance. As I live by the coast I went for these panels as the seemed to be the only ones which had a guarantee against salt corrosion.
 
ok i know it was a great day today but just got my flat plate panels up and running, finally got my 300 litre tank filled last night, so at 7 pm this evening my controller was showing 67c at top of tank,, i am happy so far
 
My parents got the tubes in a month or two ago and they are absolutely raving about them. Even before the great weather this weekend every time they turned the tap on the water was hot. My mother had a bath last week and filled it to the top and the water was still scorching afterward- this was only after the week of rain so it was only 1 or 2 days of moderate weather.

They havent looked back. they havent used their t90 electric shower once. We are looking into getting them ourselves. If its like this in the Summer- we get more sun in the winter than the summer so im looking forward to see how they get on in the winter coming

BTW it was a local supplier and fitter (Dublin south west) who was great. In and out, very tidy and great value.
 
Saying tubes are better than panels is like saying cheddar is better than cream cheese. But there are hundreds of different types of each so you can't lump everything into the same bunch.

In actuality every collector (whether vacuum tube or flat panel) performs differently. Yes, IN GENERAL vacuum tubes are more efficient than flat panel as they are better at collecting and retaining diffuse radiation in cloudy weather. However some models have great efficiency and some have very poor efficiency so this is not always true.

Quality of glass, quality of insulation, quality of materials, etc etc all affect the performance of the panels. This affects how well they collect and retain heat. This affects the efficiency of the panel greatly.

We ran a T*SOL comparison on 2 vacuum collectors with the same aperture area from the SEI registered list last year and one was 45% more efficient than the other. Buyer beware!!!

If you're interested we have a short guide on our own website. Just google "solar collector efficiency equation" with Pages from Ireland on if you want to read more about it. It's a bit dense but it has some graphs showing the difference between performance in Flat vs Vacuum.

Cheers

Des
 
we've had our solar panels up and running a few weeks now, we're getting temperatures of about 55-60 degrees for the last week and the temperature drops about 5-7 degrees overnight.
am plesantly suprised with these temperatures as the panels are west facing.
 
one issue our plumber raised with us when deciding between the two - very easy to break vacuum tubes + kids playing football/hurling in garden = bad idea. We have a bungalow so may not be an issue with 2 story but still was something we nevr thought about. had more or less decided on tube s but this has changed our mind
 
You must log in or register to reply here.
Back
Top