Solar Panels/Tubes

sman said:
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
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This is true sman, flat panels are more resiliant, but bear in mind tubes can be easily replaced if broken (replacement glass tubes are in the order of 30-50 euro to buy). If someone manages to break a flat panel with a sliotar or football the whole thing generally has to be replaced!
 
Hi,


Using solar panels is a great way to generate clean and renewable electricity to power remote appliances, or even the average home. There are two main forms of solar cells in existence today, and these are; "solar electricity panels" and "solar hot water panels". The two different technologies allow us to either generate electricity for our homes or to heat the water we use.
As time goes by, we begin to see new and more efficient solar panel designs. This is making the use of photovoltaic power over fossil fuels, much more viable to homeowners and businesses.

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Hi,

Just starting a self-build at the moment. We were all for installing the tubes instead of the flat panels as the general consensus is that the tubes are more efficient. However we have just received three quotes from plumbers. Two strongly advised against putting in the tubes as from their experience they can be quite problematic. The third actually refused to do our plumbing if we installed the tubes! We are building a two-storey house so balls should not be a problem. Has anyone experience of tubes causing hassle? Hadn't heard any bad stories up until now.
 
The only hastle I can can see from the tubes is that you have to leave a bit of scaffold up so you can put in the tubes ( into the manifold) when all the plumbing is complete & the ESB is switched on. Apartenetly they could damage the manifold if they were put in & there is no water in the system.
 
Thermomax tubes appear to be the best quality in ireland at the moment and are manufactured in northern ireland. Tubes are approximately 10% more efficient than flat panels but it is a good idea to fit a heat dump on the solar circuit and a mixing valve on your hot water supply to your sanitary appliances. Hope this helps
 
HI did you get sorted on the solar? I have done a lot of work with both tubes and flat panels so could maybe answer your questions or see if you have a good price?
 
We have tubes and can recommend them, they were very easy to install and work in the winter as well as the summer. Do you want the prices? They came from kedco and they sort a good installer so maybe that is the difference.
 
bamboozle said:
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.
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There are two types of solar panels or solar cells suitable for domestic use.
Flat Panel Arrays and , (more than one) Evacuated tubes are available in different heights and widths.
Most are about 1m2. Evacuated tubes work on the same principle as the flat panel solar cells, but due to their design are far more
efficient at collecting solar energy Evacuated tubes have been around for years and are extensively used in Canada,
Germany, China and England. Evacuated tubes use a twin glass tube made of borosilicate glass which makes them extremely durable.

This type of design allows maximum absorption with minimal reflection. The top of the tubes are fused together and all air within the tubes is pumped out at the same time the tubes are exposed to extremely high temperatures.
This "evacuation" of the gasses forms a vacuum, which is an important factor in the performance of the evacuated tubes.

Due to the vacuum process the tubes are extremely efficient at collecting heat from solar energy
A vacuum is excellent at insulation which is why the tubes were designed as such.
The vacuum prevents any heat loss from the tubes due to the highly efficient insulation properties.
The inside tube could be as hot as 150C while the outer tube is cold to the touch.

Due to this design evacuated tubes out perform the flat panel models and collect maximum even in bad weather.
 
Hi, I have 4 flat panels on my south facing garage and I'm very happy with them. These days we always get 50degress in the tank. I found that the solar controller needed a bit of tweeking to help it along. For instance the start up function was turned off. This features monitors the panel temp in the morning and starts pumping fluid up to the panel to help it heat up quicker.It's also good for overcast days when the sun isn't shining to get them started. When turned of it heats the fluid in the panel, pump comes on then pumps cold fluid into the panel which then knocks the pump off. It never started pumping before 10am before I switched it on, now it's pumping from about 7.30am. Also the difference temp setting between the panel temp and the tank temp was far to high. The panel had to be 8degrees above the bottom of the tank to start the pump, changed to 6degrees and works far better. All these are trial and error though. The only thing I find funny about my system is, in March one very good Sunday we had 80degrees at the panel and 72degrees in the tank, now we get nowhere near them temps even with the sunny longer days. Has anyone else come across this? Also has anyone else adjusted their solar controller for the better? I think the factory setting just don't suit Ireland.
 
This is quite an old post, which I just stumbled on (while searching for something else) but if you're still awake on this one, then you are right to have changed the temperature difference setting on your controller, but not the "start up" one. The start-up one is really for a very specific type of vacuum tube (direct flow) where water can get quite hot inside the tube, but not at the manifold (where the probe is). This doesn't apply to either flatplates, or to most heat-pipe vacuum systems.

As to why your system would appear to have deteriorated - this can be subjective. Sometimes a household will use no hot water one day, so the cylinder starts off at 60 degrees from the day before, gets brought up to 72 quite quickly. If you start the day with the cylinder at 20 or 30 degrees, its a different matter. But if you have four panels, I assume that equates to about 8 sq m. Your cylinder should be well above 50. I wonder if there is something else you have accidentally reset? If you pm me your controller type, I may be able to help.
 
anyone have any reports on these guys " Ecolodge Renewables Ltd " ,they seem almost too cheap
 
Just be aware that when they describe a 4 sq m panel, they mean gross area. The actual aperture area can be calculated by dividing the grant by 300. In the case of the 4 sq m panel, that's actually 2.95. Also the systems don't include a heat dump, or provide the facility for one. When you go away on holidays, or don't use the hot water, the panel will boil, degrading antifreeze, and keeping the whole system under steam pressure until sundown. I'd always prefer to see a heat dump used, especially with vacuum systems which can reach 220 degrees.
 
I have a great location for solar panels on the back of my house, and the south facing roof is 2 storeys high so would be safe from any potential damage.

I sit out the back the odd day, and even when its not that hot (like last couple of weeks), I'm amazed at how much heat my back garden gets. Due to this I got to thinking that solar panels/tubes might be a decent buy, if I coudl get them with a grant.

But from all the posts I have read, it appears that they might never actually pay for themselves. I'm not the sort of fool who would buy a thing just to be eco-friendly. It would still have to save me money.

I like the idea of always having hot water on tap but if I could do it cheaper using electricity then the solar would be a non-starter.
 
While I wouldn't regard environmentalists as fools, the strictly financial viability of solar panels depends on a number of factors;

Energy Inflation What price trends you expect will apply to other energy over the life of the system. If you believe in peak oil, then all bets are off on what might happen when this recession bottoms out. The last time demand exceeded supply, oil prices went up by 700%, or by $120. Many expect the prices to go to $200 or $300 per barrel very quickly.

Panel Prices It could be argued that installation prices are falling (and they have done in recent years because solar moved from being a niche product, into the mainstream), but we are also reaching peak copper, and energy prices are starting to have a serious bearing on the price of other components of a panel, such as aluminium. Margins in the industry are screwed to the floor and I would expect prices to rise in coming years.

How much hot water you use - If you only take frugal showers, there are only two people in the house, and you use a dishwasher and washing machine that can't be filled with hot water, etc., then you may find your hot water useage is reduced

Your Heating System If you already have a very efficient hot water system such as a gas fired combi boiler, then the savings will be reduced. But most houses have the heating turned off for six months of the summer. During that time, the hot water comes from either an immersion heater, or by switching on a boiler, heating boiler, flue and miles of pipework just to heat a cylinder in the hotpress

Your existing cylinder - this will be replaced with a solar one. If the existing cylinder is wasting heat, then there will be year-round savings on this. Changing the cylinder is a substantial chunk of the cost of a solar installation.

At current energy prices, a solar water heater can give a payback period of about 12 years in situations where the the existing heating system is as above. Thats a return of over 8%. I think the new government solidarity bond is offering about half that?

In my own situation, our central heating is off for 8 months of the year. I fill our washing machine with hot water from the tap (using a short hose on the tap in the utility room) and we like baths. Its a no-brainer for someone in an energy efficient house whose heating is off all the time. A bit more difficult to say for an old and cold house with a really efficient pellet boiler that is on a lot of the time.
 
What questions should I ask the solar panel system sales people ,Ive had 3 to my door now and each one has a different pitch ,I honestly yhink they dont know what they,re selling
 
1. Ask them if they have an Irish plumbing/heating training background and have they completed the solar installers course (SEI regitered). Not a dodgy cert that was picked up from under a mushroom in a forest!!
2. Is their product tried and tested.
3. Have they insurance.
4. References from previous satisfied customers.
 
I would be inclined to put these the other way around. Like references at the top of the list. Everyone is going to say that their product is tried and tested, and to my mind the SEI registered training is of mixed quality.

I think you need to have a clear idea of what you want yourself. For example, you should know yourself whether you want flatplates or tubes rather than being open to persuasion by the door-knockers. Tubes have a longer operating season because of their better insulation, but will need to have the tube part replaced after about 20 years. With the Chinese vacuum flask system, replacement flasks are about €5 each, but the single glass tube type would be way more expensive at that stage. Flatplates, by comparison, are a lot more durable and should last 40 years. They are more aesthetically appealing to some, but also more expensive to fit.

One thing. Never ever sign a contract during a house call. There are companies putting pressure on people to sign for a project with promised discounts on the night. The deals are some of the worst I have ever seen in this business. Q
 
I am a first time poster so please forgive me if I am asking something that seems very dim, we have planning permission for a two storey house and are planning to use solar panels to heat both water and to power either underfloor heating or wall panel heating, from reading this thread it seems very controversial as to the benefit of solar panels, can you tell me does anyone have experience of using solar panels for heating as well as water and how successful they are.
thanks in advance
 
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