Solar panels to heat water - flat panels or evacuated tube?

Question

We want to put solar panels on our roof to heat our households water. Is it better to go with the old technology - flat panels- or the new technology - evacuated tubes? We want it to last as long as possible because it is so expensive to put up!

Answer 1

evacuated tube every time trust me

Answer 2

Yes evacuated tube

Thats them

Answer 3

Zam is pretty much on the money. Depends on location, ie how much sun you get, how much space you have and the relative costs. We use panels as they work out a lot cheaper, are more tolerant of faulty installation and are more robust. In fact our glass panels to increase the efficiency of the collectors have been broken long ago by stone throwing children, but we still get plenty of heat from just 2 panels supplying a 300litre tank. But then we live in the tropics, so sunshine is not such a rare event. We even disconnected the standby electric heater in the tank and it results in just 3 or 4 days a year of luke warm water, as opposed to the normal hot!

Answer 4

it depends on where you live, as to what kind would be most economical for you.  Did you know that there are some energy companies that are willing to give you a deep discount if you are willing to use their resources or people to install your solar panels.  With the ever looming energy crunch ahead, I congratulate you on making such a fine choice to heat your water.  I hope to see more and more people realizing that this can help the environment and save them on their bills.  If I were you, I would go to a search engine and put in the words solar panels to heat water or just key words that help them help you locate what you need.  I pulled up a few such pages, they even had a talking guy on one of them it was very amusing.  I am sure you are likely to find something within your price range but I do request that you would least call your local electric company and asked them if they have a policy or a rebate or discount to get your heated panels through them you would be surprised that there are some even a growing number of energy companies helping people help themselves.  I hope this helps you, you have a nice day.

Answer 5

If you want your solar panels to last long, it's important to choose a closed loop rather than an open loop system.

Closed loop has the same fluid circulating in panel all the time. It then transfers the heat to your hot water.

Open loop circulates your actual hot water through the panel. This means that debris and calcium that might be in your hot water can get stuck in the solar panel.

This greatly reduces the panel's efficiency and lifetime.

Evacuated tubes are more efficient than flat panels, so you do get more bang for your bucks.

Answer 6

We were told tubes! please be very careful before agreeing to a company to supply and fit, a friend of mine has them fitted and he says, he is not happy with the results, and he has a giant sign advertising the product, stuck in his front garden!! we contacted the same company who offered us the same package but for £6000 cheaper, very strange, so for now we have put ours on hold, and looking further into it!

Answer 7

I don't think there's a "right" answer; the factors are

1) tubes are more efficient, but cost a lot more. The lower efficiency of panels isn't necessarily a problem, since the sun is effectively unlimited, so you can put up more panels (unless you have limited space). So you need to know the specific costs of each compared to the amount of water they heat; this varies with suppliers - but in many cases, tubes will be cheaper.

2) how robust they are. Tubes can be a little fragile, where as you can usually jump on a panel without damaging it. So are you likely to get anyone throwing rocks?

3) how accessible they are; tubes can get very (very) hot - you don't want children or animals touching them.

Answer 8

Stay away from the evacuated tubes.

To be effective they have a vacuum inside the tubes.

However no vacuum will last for a long time.

The vacuum will slowly fail and soon they will no longer function.

Also note that the vacuum can't be "recharged", once its gone the tubes must be replaced.