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PeterAC
6th October 2009, 12:12 PM
Just looking at the solar hot water rebate. What is the best brand to purchase ie using the most efficient / cost effective solar panels. I've looked at Dux (good it is Australian) but don't know enough to wade through the mountains of propoganda of all the other brands etc. Look forward to feedback as I want to purchase it soon.

Regards
Peter<><

Matt
7th October 2009, 09:14 PM
Make sure (and I mean SURE) that the tank is 316 stainless.Otherwise you are looking at corrosion.

Hills make expensive ground based remotely coupled system with glass tubes. Solar Edwards or Beasleyt otherwise for close coupled systems. Work well.

I have the Solar Edwards, 10-15 yrs old but works very well and no worries about corrosion, whcih all the others do. You do not need frost protection in Newcastle so get the cheapest simple unit, no protection required. 300 litre tank with 3 flat collectors will do the job well as long as the roof is strong enough, double up on the truss elements with pine, liquid mails and bolts, only required on the top piece.

Matt

Johnnojack
7th October 2009, 09:50 PM
Stainless is not necessarily better than steel tanks which are lined with vitreous enamel (so the steel has no contact with the water anyway). Provided the anode is changed at appropriate intervals a SolaHart for instance will easily last 20 years. Check out a 302L which is fine where there is no frost. Split systems cost more and have a pump and controller which do fail. I have helped to install lots of solar hot water systems. If you have room in the ceiling for a tank then a Beasley constant pressure unit will outlast anything but I don't think they still make them.

pangit
8th October 2009, 02:37 PM
I got a Solahart split system about a year ago and it works reasonably well. I'm not in the best location as the sun disappears behind trees about 2pm at this time of year, so it still needs electric boosting except in the summer. Split systems are supposed to be a bit more efficient as they actively move the water with a pump, but of course you lose some heat in the pipes so it depends on how far the tank/collectors are apart.

Also with a split system if you can put the tank in the same place as the old one your installation costs will be less as they won't have to re-route the pipes/power.

If you have town gas you might want to look at a gas boosted system (either storage or even better instantaneous), but if you have to go for electric make sure you still use off-peak electricity, as your bills could actually increase if you are using peak. Not so convenient of course as you can't turn it on during the day to boost it.

My tank is vitreous enamel as a stainless tank was an expensive option, so I'll just have to remember to get the anode changed. According to the installer the Solahart tanks are better quality than the standard Rheem ones, but I'm not sure how true that is as they are owned by Rheem now anyway!

I looked at the evacuated glass tubes, and although it would have been a bit more efficient they were a lot more expensive - so not really worth it unless prices have come down since then. They work better in cloudy weather, and are still nearly as good when the sun is not directly overhead (as there is the same solar gain on the side of a tube as the front).

Johnnojack
8th October 2009, 09:34 PM
I agree Sean. In fact I have an instantaneous gas booster after my solar.
As for Rheem and Solahart they are different tanks even though Rheem own Solahart. You can also get a roof mounted Solahart with a gas booster in the tank. Great for offgrid homes where electricity is solar/battery (using LPG as the gas)

Alga
9th October 2009, 05:59 AM
Since they introduced the SHW grant prices have doubled, however there is an alternative which may interest people. A mate of mine sells 70 and 200lt evacuated tubes units for about $500 and $1000 delivered, I have a 70lt and it works fantastic and we boost it from our wood heater. They are self install and you don't get the rebate as that would increase the price. Rebate sellers have to be licensed by the government which is pretty expensive, hence the price rises. So really the rebate is just giving manufacturers a bigger profit margin and small importers and manufacturers can't compete.

It's the same with the insulation and solar cell rebate, the prices just double and people get ripped off even more. If anyone interested, just email chris at

bulsta57@hotmail.com

or Special Deals (http://www.2csimports.com.au) where you can view them, you'll save a heap.

PeterAC
10th October 2009, 07:44 PM
Have spent a few hours trying to read through the info on the net coupled with replies. Thanks Alga, I like your mates gear. I don't have time to spare to do the job myself but have decided to look at the hills solar water heater as well as the edwards. Both cost but hills is Oz and I have read only one poor report on them. Don't know if hills is overkill for Newcastle, I know no frost at my place but am keen on best dealing with cloudy days and future shade from trees interfering with direct sunlight. This is why I may consider the hills. Thankyou to everyones replies, as usual you blokes always come through!

Peter<><

Nuddy
9th February 2010, 10:48 AM
Pity I didn't see this earlier. We have been solar hot water users since 1985. We had a Edwards SS system at Brooklyn with the tank on the roof. Worked well for 27 years and hardly ever needed to turn on the booster. We sold the house and it promptly stopped working. Pity the new owners as there is no rebate for replacing solar with solar so they are fitting a small s/h electric heater for a few months before they upgrade to solar and get the rebate.
Meanwhile we got a Dux (Ecosmart Newcastle) 400 litre 3 panel split system (tank on the ground) last August. We ran the booster the first night after installation to get it hot initially and not had it on since (7 months). Plenty of hot water at all times but 400 litres and 3 panels is a lot for just 2 residents.
Our first bill with it on showed our electricity usage had halved from 10kWh/day to 5 kWh/day however since the old system was off-peak (8.4c/kWh) and the price of electricity has gone up from 12.7c to 15.6c
the bill was nearly the same.
Very happy with the system and we are now looking at photovoltaic panels to grid connect and get a cheque instead of a bill.