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Reliability of Solar HWS

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Started 3 years ago by Solgen
Latest reply from hamish05

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CunningPlansDept
Member

Sunshine - "It is also illegal to install solar hot water systems and solar PV by DIY." What's the source of that?

Questionman - My motto is "Anything's possible (just usually costs too much)". I've got an 18-tube 100L roof tank Solar Science HWS that I picked up for $450 (50% off sale) at FXLarkin in Wollongong that I'm planning to use as a spa heater, but I've also been considering hooking it to our existing gas HWS with a recirc pump. Through my work as an engineer I've had to design some industrial process heating systems using a standard electric HWS. From that I've got the appreciation that it's really just a pressure vessel with two threaded holes.
For your system, you've already got the recirc pump to the storage tank, so you should be able to turn off your electric heater, plumb the outlet to an instantaneous gas system inlet _that is rated for hot water at inlet_ and off you go. The gas fitting is something you'll want to get a plumber with gas-fitting licence in for unless it's only as complicated as your BBQ. (Always soapy water leak test!)

Posted Friday 30 Oct 2009 @ 10:46:57 pm from IP #
Sunshine
Member

Cunningplan,

Are you implying anyone can do 240v wiring, mains gas plumbing and mains pressure water plumbing in their premises as a DIY?
You need to do some research on the internet on those subjects.

Posted Friday 30 Oct 2009 @ 11:15:09 pm from IP #
Sunshine
Member

Questionman,

On the photos it just looks like that the gas boosted systems just connect up to the storage. I would say the gas system sits inline with the hot water output side of the tank, so the solar hot water acts like a pre-heater, if water is hot enough, it would flow through the gas system without it turning on. If the water is lower than the gas thermostat setting the gas system would kick in and boost the hot water.
I'm sure it would be straight forward.

Posted Friday 30 Oct 2009 @ 11:18:50 pm from IP #
Greenozi
Member

Sunshine
I am interested in science and research behind renewable technologies.
Besides happy customer voices like yours, sounding like paid advertisement in order to sell more products.
Good science is based on material knowledge and extensive testing, comparing different technologies, critical approach in order to improve.
Before any HWS may hang on customer roof extensive testing must be performed. There is niche market that scientific, engineering, innovators and decision making spheres may freely discuss and review.
I can see only there my small contribution not in generating "sales".
Since average customer is only interested in peace of mind that his lifetime saving spent on i.e HWS last for eternity, my approach is to find weakness, faults, check if same effect could be achieved at lower costs, propose improvements.
It is not for fait-hearted to find out that the latest, most expensive item just bought is not perfect at all.
There is the difference in attitude and sincerity.
Your plumber give you 20 years guarantee on your one thousand dollars worth investment (or 1k material and 5k labor) in solar system (even knowing that he may: bankrupt 5x in the meantime, technology may be obsolete in 10 years time, may have heart attack due to smoking in next three and die).
The best rocket scientist does not make any promise that 10 billion dollar vehicle carrying 7 lives onboard reach the outterspace in one piece.

Posted Friday 30 Oct 2009 @ 11:36:42 pm from IP #
dymonite69
Member

I agree with Greenozi. It is pointless for alternative technology to be a fringe hobby for gadget freaks. The reliability and effectiveness of these products are obligated to be of the highest order if there is going to be widespread uptake. Customers should be reassured that these items will perform as specified over the long-term. Although the technology is in relative infancy, the quality and service so far has proven to be variable and patchy. I compare this to buying the cute Alfa for looks and status versus the Toyota for durability. I am alway going to buy the Toyota. It's going to do the job it was meant to do and not break down with a pulled hamstring every 5 minutes.

Posted Saturday 31 Oct 2009 @ 12:23:59 am from IP #
blackheathan
Member

GreenOzi

I agree with you to get the technology out there! and like your approach. These technologies will never take off if it's only something that the well-off can afford due to the VERY high prices being charged for systems that qualify for rebates, and for a 10-20 year warranty that may never be upheld for reasons like you suggest.

I'm looking into organizing a community bulk buy arrangement for our area of both the good quality evacuated tubes like you were "selling"/ organizing for $900, and the pv panels for around $2.5/ watt, and have been looking for a reliable source. Any way to contact you?

Posted Saturday 31 Oct 2009 @ 12:57:52 am from IP #
Sunshine
Member

Greenozi,
The installers/plumber don't have a warranty of 20 years, the warranty is with manufacturer of the equipment. Therefore with careful research I chose both of my manufacturers of solar pv and solar HWS companies which are 60-100 years old, so they have a track record of producing quality equipment, and minimise the chance of the company folding during the warranty period. Both companies I chose also have a company distributor presence in Australia, which make warranty claims easier.
Some direct imports like found on Ebay are direct imports, with no local distributor in Australia, so warranty claims would need to be made with the company in China, if the installer/retailer is unavailable further down the track.
Not sure where you got $5000 of labour from for a system which cost parts and labour $4800 installed.
You shouldn't make up prices to make your point stack up.
Your quote "technology may be obsolete in 10 years time", doesn't make sense either.
I can't see solar going obsolete anytime soon, fossil fuels more like it.
I am getting a 10% return anyway with my investment which I am happy with. It doesn't matter if it becomes obsolete, it will still return 10%, even more when cost of power and gas goes up, so it a future proof investment really.

Posted Saturday 31 Oct 2009 @ 10:33:23 am from IP #
CunningPlansDept
Member

Sunshine - re; Legalities. I wasn't implying that. But solar HWS and PV can be done off mains and low voltage, so DIY, which your blanket statement didn't allow for, hence the question of source.
Just as we can't lull people into a false sense of security, we need to be careful of scaring them off considering work-arounds.
Not seeking battle, just clarity.

Posted Saturday 31 Oct 2009 @ 11:06:45 am from IP #
Greenozi
Member

re prices Sunshine
Just few minutes ago on next thread: ..."Thanks Guys for your help and I must say I received my quote for the 315ltr Apricus and am shocked at the price before rebates and RECS it comes in at 6150"...
Anyway
If you spent 25k on your solar W and PV, good on you, you can afford it,
But
Many people in this country may have problem to pay for such prosaic utilities like hot water and electricity that much.
They may have children at school, family to feed, other priorities and 25k means a lot for them. Even if they have got green loan that also must be eventually repaid.
We all here on this forum like renewable technologies but world don’t end here.
And
If there is Alternative cheaper option let’s talk here on this forum (isn’t it that sole purpose of this website? I don’t have exclusivity on truth; there is never the only one right way. Even in rich US (I saw on Discovery TV) there is guy driving from farm to farm and pubs installing hot water system made of black painted barrel, plywood reflector covered with aluminum foil and transparent plastic sheet ! It this is perfectly legal!! If I have to choose sides I am with this people that need help not with greedy industry. Closing our market on new ideas in order to protect the few disadvantage us whole as nation.
What happened if tomorrow newer device will be invented that produce twice as much for half price (water or electricity)? Should we close our border to keep installers industry happy or rather took full advantage of that.
That happened already with our automotive industry and now we have the most expensive cars, least efficient fleet and industry on prolonged CPR. If you dispute that I am ready to buy you an air ticket to any other continent to have a look outside the box.
If we, as customers can keep constant pressure on our suppliers and allow competition amongst them that is good for both them and us.

Posted Saturday 31 Oct 2009 @ 11:24:46 am from IP #
questionman
Member

30 Apricus tube, 315 liter stainless steel tank, 26/li Rinnai gas booster , cost before RECS and all rebates is $7444 of which customer has pay $5576 upfront because he has to be the one to apply for federal rebates. So a $6144 quote before RECS and rebates is more reasonable than $7444 initial quote which is still considered inadequate and was withdrawn by Apricus agent. Only high-income Australians and wealthy ones can afford to pay this; even after RECS and rebates, the net payable is still almost $4700. This evacuated tube solar hot water system can only be financially accessible to the wealthy and high income Australians. Lower income and pensioner Australians , if they can afford to pay $2600 net after RECS and rebates for a solar hot water system , have to make do with the less efficient, higher maintenance flat panel system. The solar hot water system's market will be divided into the haves and the have-nots. I wonder whether the government can do something about this. The people who can least afford higher living expenses will have to choose a system which is less efficient - hence more boosting required, - and cost more to maintain as flat panels are more expensive to replace and more breakable than tubes.

Posted Saturday 31 Oct 2009 @ 1:20:01 pm from IP #
Sunshine
Member

questionman,
I know Qld government have a $500 solar hot water system deal and $100 for pensioners.
It is flat plate system, not sure if they offer split though.
My roof isn't strong enough, so I was forced to go to a split system, as engineering costs are more expensive to strengthen roof, than to pay the extra for a split system.
Plus, for some reason or another I have never seen an evacuated tube system with tank on the roof, they seem to be split as standard.

The more efficient appliances, cars, planes etc etc are always seem to be more expensive, as the manufacturers need to recoup their R&D and engineering costs, whilst older technology is cheaper as they just need to be copied and mass production reduces costs. I can't ever seeing that changing, as new technology is always charged at a premium.

Posted Saturday 31 Oct 2009 @ 11:02:05 pm from IP #
Sunshine
Member

Greenozi,

You say I can afford it, but other people can't. Interesting you say that, but you may be surprised to know that I earn less than the average Australian weekly income, single income family, have children at school and have a mortgage. So I have the same costs as other families.
However it is interesting to see when I speak with other people who say they can't afford solar, they drive a $45,000 petrol guzzling 4wd, drink and smoke like there's no tomorrow, and earn 2 or 3 times what I earn, and they say "solar is too expensive".
They also get a $700 quarterly power bill, which they can probably afford anyway.

I don't smoke, have been working for 25 years now.
So doing the figures...
So I have saved $20/week by not smoking, $1000 per year, saving $25,000 over 25 years by not smoking.
So in reality I got my solar for free as against a long term smoker.
The moral of the story is, it's not what you earn, it's what you do with your money.
A good lesson in life.

Posted Saturday 31 Oct 2009 @ 11:12:46 pm from IP #
rockabye
Member

Don't be put off by the lower efficiency of flat panel solar hws. I've been using them either in rental or in my own home since 1978 and never had any maintenance issues of any significance. The one I owned for 12 years had minor leaks from the safety valve because we had bore water but otherwise worked perfectly. It's now 18 years old and still going strong for its current owner.

What appears to have happened though is govt rebates have pushed prices up to unjustifiable levels. The high no of systems being installed should be bringing prices down, instead there appears to be significant profiteering going on.

I think the Qld govt approach of providing systems for $500 or $100 for pensioners is a far better approach to rebates. The govt can negotiate the lowest price because it is 'buying' in bulk. This is similar to their recent very successful 1kW solar PV scheme. By putting 1000 systems up for tender they got a fixed price which ended up costing each homeowner only $185. An added bonus was the fed govt means tested the $8000 rebate which kept the benefits to those who could least afford it.

Posted Saturday 31 Oct 2009 @ 11:45:09 pm from IP #
dymonite69
Member

Hey Sunshine,

I have a former colleague. DINK (with no intention to have them)- both on six figure salaries. Doing a 7 figure architecturally designed reno. He can't afford rainwater tank because 'you try to do the right thing but these things are too expensive'?!

Having said that I can't see why a solar HWS should be double the price of a conventional one.

Posted Saturday 31 Oct 2009 @ 11:46:29 pm from IP #
dymonite69
Member

I am not sure where the evidence is that evacuated tubes should last longer than flat plates. Are there any figures around that show what percentage are still working after 15 years? And it's not just the collector that could fail, it can also be the tank. The average tank life expectancy for conventional systems is around 15 years.

Posted Saturday 31 Oct 2009 @ 11:49:02 pm from IP #
Sunshine
Member

dymonite69,

I agree, I would prefer to pay less too, but you have to way up price, performance, quality, style etc etc.. that's a personal choice.
Look at the wide variety of car brands and colours on the road. We all have different ideas.

Posted Saturday 31 Oct 2009 @ 11:52:58 pm from IP #
Sunshine
Member

The Apricus and Hills systems both come with Everlast stainless steel tanks rather than vitreous enamel steel. Vitreous enamel steel tanks last around 15 years plus need regular anode replacements, which add to the overall cost, stainless tanks last around 25 years.
That is the main difference in durability.
In my area there are alot of old solar hot water systems, but they all seem to have a horrible looking mouldy sort of growth in them (behind the flat plate glass)
Looks awful, and as water flows through it, am unsure how safe the water is.. yuck.
The evacuated tube system has only 1.7 litres of water in the manifold, plus it's not see through, so no sunlight is able to get to the water, so no mould or algae should grow on these.

Posted Saturday 31 Oct 2009 @ 11:58:03 pm from IP #
rockabye
Member

I think the stainless steel tank is good investment. I went for a Solar Edwards back in 1991 for that reason. They were no more expensive at that time because they had a small market and one main competitor Solarhart.

Now I am using a heatpump which is inferior to solar hws, at least in my climate, however it still uses a lot less than the old electric hws. The prices being charged are far in excess of their manufacturing cost as they are made in China like most things these days.

Posted Sunday 1 Nov 2009 @ 12:28:44 am from IP #
Greenozi
Member

Very encouraging news from QLD, Rockybye.
Sign, what one bulk buyer, one strong voice can achieve.
Whatever prevent us from converting 99% HWS to solar is bad for economics and bad for science (prohibitive costs, bad habits, red tape).

Let’s do simpyfied calculations of the cost of ownership.
Investment $6.000
over 15 years, (20 years)
commercial interest 7%,
+ two calls $500 ea (i.e replacing valves or pumps).
TOTAL COST: $17.045 (?? I am almost surprised myself) ($24.563!!!!!!!)

Days in service
15 years . . . . (20 Years)
365 days . . . . (365 days)
============================
5475 days . . . . (7300 days)

Cost per day
$17.045 / 5475 = $3.11 or per month 17.045/15+12= $94.69 (!! That is close to Electric HWS or more?)
Summary:
That is prove that for any economist in this country pushing to replace whole HWS fleet is not an option at nowadays costs and scenario.

I. What GOOD CAPITALIST can do?
Can grab your $6000 cash, install state of the art SHWS on your roof and sign a contract to supply you free hot water for next 15 years. Obviously enterprise similar to Power Company will be able to setup everything and run smoothly at the fraction of your costs.
II. What FREE MERKETER could do?
Cut red tape, introduce competition, simplify regulations, and let market regulate prices that will see eventually 50% of least efficient suppliers gone busted with total gain for community as whole. Prices may drop to the level allowing 3-4years return on investment.
III. What IDUSTRIALIST SHOULD DO.?
Buy a piece of programming software for automotive plants in Geelong that allow industrial robots there could crank out 300L cylinders instead of 4 liters. Melt the sand to blow some vacuum tubes. Send the excess of first class product SHWS overseas.
IV. What SOCIALIST WILL DO?
Shut and seal or just remove your RED tap valve and problem solved. Now on only cold water and shower is the healthier option. Problem solved.
IV. What do YOU think we should do?

Posted Sunday 1 Nov 2009 @ 2:27:52 am from IP #
rockabye
Member

I haven't checked your numbers but assuming $3.11/day for hot water say for a household of four. We are looking at $0.80/day/person. Now most people spend 5 times this amount on their first capuccino or bottle of water on the way to the office. Sounds like value for money to me, PLUS a massive reduction in household energy requirements nationally.

Then there are all of the jobs for people building, transporting, installing and maintaining these low energy devices. Even the accountants and office staff get a job out of it. What value do we place on employment?

Posted Sunday 1 Nov 2009 @ 2:55:38 am from IP #
Anonymous
Unregistered

I think, if you buy the product from some reliable company, the tubes wall last long, and will give you good output. Try to compare the products at http://www.todae.com.au/SolarPanels/SolarPanels

Posted Sunday 1 Nov 2009 @ 4:26:42 pm from IP #
Russell Moore
Member

I still have an old flat plate Beasley solar HWS that I had installed in 1983, and it is still happily giving us 'free' hot water, for well over 26 years now.
I think I have replaced two frost valves in that time.
The only thing I did to it was to place a 'reflector' made out of five ply sheet and some silver insulation foil vertically between the panels and the tank.

Posted Tuesday 24 Nov 2009 @ 12:11:50 pm from IP #
Bobthe...
Member

I too still get perfect service from an almost 20 yr old SolarHart.
Using the heat exchange tank, with glycol in the panels is good in our frosty area.
When I bought it from a field days demo (it was the demo unit) very cheap (we can't all afford full price & installation) I opted to have no boost. They supplied me with an old element end plate to close the tank. I also put the tank inside my roof ridge on a steel frame, so the ugly tank is not visible. The panels are down the 30 degree slope a bit, so the thermosyphon works just fine. In hot midsummer I put a sheet of cardboard over about 2/3 of the panel area to prevent overheating.
We have a separate wetback system, with changeover tap, for the worst winter conditions.

Its all perfect...... no power..... no gas..... natural thermosyphon.... about 30 minutes service every 5 years, to top up the glycol and change the annode.

There's no way a tube system with circulating pump is better.

Bob

Posted Wednesday 25 Nov 2009 @ 12:16:29 am from IP #
Sunshine
Member

Greenozi,

I have used your calculation methodology for an electric vitreous enamel system over 15 years, with NO increase of power cost included. I've left it static as $600 per year.

The electric system is still way more expensive than solar, around $5000-$6000 more expensive. But we all know cost of electricity will go up over 15 years, so real cost will be much higher.

Let’s do calculations of the cost of ownership for an electric vitreous enamel system over 15 years .
Investment $1.500
Yearly power cost $600
over 15 years,
commercial interest 7%,
plus system replacement after 15 years $1500 (as electric systems are usually vitreous enamel)
+ two calls $500 ea (i.e replacing valves and anodes).
TOTAL COST: $22,839

Year 1-1500+600+147=2247
Year 2-2247+600+157=3004
Year 3-3004+600+252=3856
Year 4-3856+600+312=4768
Year 5-4768+600+375=5743
Year 6-5743+600+444=6787
Year 7-6787+600+517=7904
Year 8-7904+600+595=9099
Year 9-9099+600+679=10378
Year 10-10378+600+768=11746
Year 11-11746+600+864=13210
Year 12-13210+600+966=14776
Year 13-14776+600+1076=16452
Year 14-16452+600+1193=18245
Year 15-18245+600+1500(system replacement)+1000 (2 service calls over 15 years)+1494= $22,839

Posted Wednesday 25 Nov 2009 @ 12:54:04 am from IP #
Brado
Member

Questionman - I have just been reading through the posted blogs on the forum and I can understand your frustration to a degree but I think I may be able to assit you in understanding the thinking of your apricus agent.
I'm in Rural Sydney and liked the idea of gas boosted solar with stainless tank also. however after speaking to my local apricus dealer he explained that this could be done but in my situation wouldn't make the most financial sense.
The reason for this was this; stainless steel tanks and more expensive for starters and because the water in my area is of a good quality I would get good life span out of a glass lined tank (which was considerably cheaper).
Further more where my current tank is positioned is a long way from the gas bottles (LPG) and he explained that the extra cost for running gas pipe work from my gas bottle location to my tank position would be significant and this would defeat the purpose of one of the reasons why I wanted to install solar. (to reduce cost). On top of this is the additional unit cost for a gas boosted system in comparison to a electric system due to the gas system having a continuous flow gas booster as a part of the system.
So we ended up taking the apricus agents advise, and installing a 30 tube 315 litre electric system and we couldn't be happier, we don't boost at all and our initial outlay in terms of cost was much much less than what it would of been should we of insisted on a gas boosted system.
So your saying you think your paying to much for a gas boosted stainless 30 tube system but I think you must understand that your paying premium prices for that stainless steel, gas boosted 315 30 tube system because it is a premium product, thats the top of the line. I say in your situation it's a bit of an over kill, you would see far better results by going with a system that your local apricus agent suggests. ie a electric boosted system in which i doubt you will boost anyway especially being in Perth!!
remember a 315 gas boosted stainless steel 30 tube system and a 315 electric boosted glass lined tank 30 tube system, receive the same amount of solar contribution. the only difference between the two systems in terms of running costs is boosting, but I can't see you needed to use your booster, and even if you do require to boost the difference in cost is so minimal.
Do yourself a favor i say, Go electric

Hope this is helpful.

Posted Wednesday 30 Dec 2009 @ 5:17:09 am from IP #
dymonite69
Member

Discounting the situation where you can provide all your hot water with your solar system, the running costs for natural gas with a solar pre-heater is always going to be the lowest.

However, this is also the most expensive set-up. Essentially you have almost two stand-alone systems in series i.e. a solar collector + tank AND an instantaneous gas hot water system.

Both would have to last a long time to pay off the capital investment (probably >15 years). It would take even longer using expensive LPG.

I would only consider this combination if a) I already owned an instant gas system and wanted to augment it with a solar collector or b) local electricity rates was much more expensive than gas

Posted Wednesday 30 Dec 2009 @ 7:15:02 am from IP #
gully
Member

Sorry questionman (going back) -
"This evacuated tube solar hot water system can only be financially accessible to the wealthy and high income Australians. Lower income and pensioner Australians ... have to make do with the less efficient, higher maintenance flat panel system."

I'm a low income family and with the help of a green loan got a 30 tube system installed for $3k the installer did all the rebates for me. Having said that i'm sure many low income families will opt for the bunnings cheapie flat panel systems.

Posted Wednesday 24 Mar 2010 @ 5:03:30 am from IP #
Buzzman
Member

What I'd like to know is when is some enterprising entrepreneur going to invent an A/C pre-heater that will plumb into ANY HWS?
Using the principle that the heat pumps are A/C in reverse, why not use the A/C you have anyway?
Someone shoot me down in flames??

Posted Sunday 28 Mar 2010 @ 7:32:23 am from IP #
stevo
Member

I have liked the idea of the evacuated tube systems, and theoretically everyone I have spoken to provides a positive comment. However I have installed an Apricus system at the beginning of 2011 and there have been slight problems with heating and the sensors reading correctly. Have been unsuccessfully trying for 5-6 weeks to get service with no response from Apricus or supplier. Don't get Apricus if you want reliable follow-up.

Posted Sunday 29 May 2011 @ 8:04:01 am from IP #
hamish05
Member

In which state do you live stevo? I have had excellent assistance from the Apricus rep in Victoria recently. Happy to help with a contact no if req'd.

I am interested in your sensor issue. Could you elaborate? I also believe they could be improved.

Posted Saturday 18 Jun 2011 @ 11:46:26 am from IP #

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